JP2000336491A - Microetching agent for nickel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an etching agent for roughening the surface of nickel into a deep rugged shape exhibiting anchor effect in the case of being adhered with a resin by forming it into an aq. soln. contg. ferric chloride, hydrochloric acid and a high polymer compd. having at least either polyamine chains or cationic groups in molecules respectively by the ratios in specified ranges. SOLUTION: The ratio of ferric chloride is 5 to 39 wt.%, that of hydrochloric acid is 0.01 to 2 wt.%, and that of a high polymer compd. is 0.000001 to 1 wt.%. The high polymer compd. is a cationic high polymer compd. showing cationic behavior in an aq. soln., in which molecular weight is desirably several thousands to several millions, and polyethylene imine, polyalkylene polyamine or the like is desirable because of the excellent solubility and low foamability thereof. For obtaining deep ruggedness, etching is executed to a depth of 0.5 to 4 μm from the surface of nickel. Ferrous ions produced by the reaction with nickel are returned by air oxidation and recover the etching performance thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microetching agent capable of roughening a nickel surface into a shape having deep irregularities. The micro-etching agent of the present invention,
For example, it can be widely used for a surface treatment of a nickel material such as a pretreatment for forming a coating on the surface of a nickel material or bonding it to another member.

[0002]

2. Description of the Related Art In order to improve the adhesion between nickel and a resin, the surface of nickel has been conventionally roughened by scrubbing or buffing. However, with such a physical polishing method, the surface is not sufficiently roughened, and it is difficult to obtain deep irregularities excellent in adhesion to a resin. Further, microetching and roughening the nickel surface with an aqueous solution comprising ferric chloride and hydrochloric acid have been studied, but even with such a microetching agent, only shallow and smooth irregularities can be obtained, and the resin and the resin are not easily etched. Insufficient adhesion.

On the other hand, as an etching agent for an iron-based alloy, JP-A-63-79983 contains a ferric salt, a polyamine, an organic sulfur compound, an organic chelate compound and an inorganic acid (hydrochloric acid, sulfuric acid or nitric acid). Aqueous solutions are described. However, when nickel is microetched with this aqueous solution, as described in the above-mentioned publication, a smooth and glossy surface is obtained, and the adhesiveness to the resin is rather reduced.

[0004] Japanese Patent Application Laid-Open No. 9-4116 by the present applicant.
No. 2 describes that an aqueous solution containing a copper oxidizing agent, a polymer compound having a polyamine chain and / or a cationic group can roughen the copper surface. However, it was completely unknown how this aqueous solution acts on the nickel surface. That is, copper is a noble metal having a higher oxidation-reduction potential than hydrogen, whereas nickel is a noble metal having a lower oxidation-reduction potential than hydrogen, and has completely different reactivity to a corrosion solution.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a microetching agent capable of roughening into a shape having deep irregularities such that an anchor effect is sufficiently exhibited when a nickel surface is bonded to a resin. With the goal.

[0006]

SUMMARY OF THE INVENTION The present invention provides ferric chloride 5
~ 39% (wt%, the same applies hereinafter), hydrochloric acid 0.01 ~ 2%,
The present invention relates to a microetching agent for nickel comprising an aqueous solution containing 0.000001 to 1% of a polymer compound having at least one of a polyamine chain and a cationic group in a molecule.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the microetching agent for nickel of the present invention will be described in detail. Ferric chloride in the present invention has an action of oxidizing and dissolving nickel. The concentration of ferric chloride is 5-39%, preferably 7-1.
5%. If the concentration is less than 5%, the etching rate becomes too slow, the processing time for obtaining deep unevenness becomes longer, and the permissible nickel dissolution amount of the etching agent decreases. If the concentration exceeds 39%, the etching rate becomes too high, so that it is difficult to control the etching amount, and it is difficult to obtain deep irregularities.

The hydrochloric acid in the present invention has an effect of accelerating the dissolution of oxidized nickel in an etching agent and an effect of increasing an allowable nickel dissolution amount. The concentration of hydrochloric acid is 0.01 to 2%, preferably 0.03 to 0.5%
It is. If the concentration is less than 0.01%, the effect is insufficient, and if it exceeds 2%, etching unevenness is likely to occur, and it is difficult to obtain a constant uneven shape.

The polymer compound of the present invention has at least one of a polyamine chain and a cationic group in the molecule, and has a molecular weight of 1 which exhibits cationic behavior in an aqueous solution.
000 or more, preferably thousands to millions of high molecular compounds (hereinafter referred to as cationic polymers). The details of the action of the cationic polymer are unknown, but it is presumed that the cationic polymer is discontinuously adsorbed on the nickel surface to create a pitting state. Specific examples of the cationic polymer include, for example, polyethyleneimine, polyalkylenepolyamine, polyallylamine, a quaternary ammonium salt type styrene polymer,
Polymer of quaternary ammonium salt type aminoalkyl (meth) acrylate, polymer of quaternary ammonium salt type diallylamine, copolymer of quaternary ammonium salt type diallylamine and acrylamide, polymer of salt of aminoalkylacrylamide And cationic cellulose derivatives. Examples of the salt include a hydrochloride. Further, as the cationic polymer, those commercially available as an antistatic agent for resin or fiber, a polymer flocculant for wastewater treatment, a conditioning component for hair rinse, and the like may be used. Among the cationic polymers, polyethyleneimine, polyalkylenepolyamine, and the like are preferable because of their excellent solubility and low foamability. Two or more of these cationic polymers may be used in combination. The concentration of the cationic polymer is 0.000001 to 1%. The particularly preferred concentration varies depending on the type of the cationic polymer,
It is about 0.0001 to 0.5%. The concentration is 0.0
If it is less than 00001%, the effect is insufficient and it is not possible to obtain deep irregularities, and if it exceeds 1%, on the contrary, it exhibits a rust-preventive action and is etched into a smooth shape.

Various additives such as a surfactant and a chelating agent may be further added to the microetching agent of the present invention as needed.

The microetching agent of the present invention can be easily adjusted by dissolving each of the above components in water. The water is preferably ion-exchanged water.

The method of using the microetching agent of the present invention is not particularly limited, and examples thereof include a method of spraying a microetching agent on nickel and a method of immersing nickel in the microetching agent. Among the above methods, a spray method is preferable because ferrous ions generated by a reaction with nickel are returned to ferric ions by air oxidation and the etching ability can be recovered. Therefore, in the case of the immersion method, it is preferable to perform bubbling or the like for blowing air.

When the microetching agent of the present invention is used, in order to obtain deep irregularities, it is necessary to use a microetching agent from the nickel surface in order to obtain deep irregularities.
It is preferred to etch to a depth of 5-4 μm, preferably 2-3 μm. The amount of etching is a value calculated from a change in weight of nickel before and after etching and a surface area and density of nickel. Further, at the time of etching, the temperature of the etching agent is usually 20 to 40 ° C., the etching time is preferably 10 seconds to 2 minutes, and the etching rate is usually 0.5 to 5 μm / min.

Depending on the type of nickel to be treated, a preliminary treatment may be performed before micro-etching. For example, in the case of a bright electrolytic nickel plating film, 150-150 3
It is preferred to heat at 00C for 20-60 minutes.

In order to further improve the adhesiveness with the resin, a silane-based or titanium-based coupling agent may be applied after micro-etching, or a rust-proof treatment may be performed.

[0016]

Examples 1 to 5 and Comparative Examples 1 to 5 Test foils were prepared by applying a 10 μm thick electrolytic nickel plating to a 70 μm thick copper foil surface. Next, a microetching agent having the composition shown in Table 1 was prepared, and the test foil was immersed in the microetching agent at 25 ° C. for 60 seconds to etch the nickel surface. Table 1 shows the etching amount. Observation of the obtained surface with a 3500-fold electron microscope revealed that the surfaces obtained in Examples 1 to 5 were all formed with deep and fine irregularities, whereas those obtained in Comparative Examples 1 to 5 were obtained. Each of the surfaces had large irregularities and a small number per unit area as compared with the examples. Next, the etched test foil was laminated and pressed with a prepreg for multilayer wiring board having a thickness of 0.15 mm (GEPL-170 manufactured by Mitsubishi Gas Chemical Co., Ltd.).
According to ISC 6481 (1990), the remaining copper foil was removed except for the copper foil having a width of 1 cm, and the peel strength was measured. Table 1 shows the results.

Comparative Examples 6 and 7 Test foils produced in the same manner as in Example 1 were polished with a buff (# 240 emery buff) or a scrub (grit grit with a G20 steel grid), and the adhesion to a prepreg was examined. Table 1 shows the results.

[0018]

[Table 1]

Note) Sanfloc 700: a cationic polymer flocculant manufactured by Sanyo Chemical Industries, Ltd. Epomin P-1000: an average molecular weight of 1000 manufactured by Nippon Shokubai Co., Ltd.
Polyethyleneimine Consensic CP-104 having an average molecular weight of 200,000 manufactured by Senka Co., Ltd.
Quaternary ammonium salt type diallylamine polymer

As shown in Table 1, the prepreg and nickel can be firmly bonded by treating with the micro-etching agent shown in the embodiment.

[0021]

By roughening the nickel surface with the microetching agent of the present invention, for example, AS resin, ABS
Resin, fluororesin, polyamide, polyethylene, polyethylene terephthalate, polyvinylidene chloride, polyvinyl chloride, polycarbonate, polystyrene, polysulfone, polypropylene, thermoplastic resin such as liquid crystal polymer, epoxy resin, phenol resin, polyimide, polyurethane, bismaleimide Adhesion with various resins such as a thermosetting resin such as a triazine resin and a modified polyphenylene ether can be improved. That is, it is possible to improve the adhesiveness with, for example, an adhesive, a paint, a molding resin, or an insulating resin for electronic components such as a printed wiring board.

Claims (1)

[Claims] 1. Ferric chloride 5 to 39% by weight, hydrochloric acid 0.0
0.000 to 1% by weight of a polymer compound having at least one of a polyamine chain and a cationic group in a molecule
A microetching agent for nickel comprising an aqueous solution containing from 01 to 1% by weight.