JPH08183776A - Surface-protecting agent of metal and production using the same - Google Patents

Abstract

PURPOSE: To obtain a compound which is a specific imidazole derivative, has the forming property of film excellent in rust-proofing property, moisture resistance, heat resistance and chemical resistance, has good wettability and spreading property of low-melting point cream solder and useful as a water-soluble protecting agent, etc., of metal surface of a printed-wiring board. CONSTITUTION: This imidazole derivative is a compound of formula I[R1 , R2 and R5 are each a (branched)alkylene; R3 , R4 , R5 , R6 and R7 are each H, a lower alkyl or a halogen; a, b and h are each 0-4; c and d are each 0-10; e is 1-10; f and g are each 0 or 1], [e.g. 2-(2-methoxyphenyl)-4,5-dibenzylimidazole], a compound of formula II [R1 , R3 , R5 and R6 are each H, a lower alkyl or a halogen; R2 and R4 are each a (branched)alkylene; a, b and g are each 0-4; c is 0-10; d is 1-10; e and f are each 0 or 1] [e.g.2-(2-phenylethyl)-4-benzyl-5- methylimidazole].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-soluble protective agent for forming a chemical conversion film on a metal surface, and particularly to a metal surface of a printed wiring board having rust-preventing property, heat resistance and moisture resistance.
It is suitable as a protective agent for forming a chemical conversion film having excellent chemical resistance.

[0002]

2. Description of the Related Art As a surface treatment method for forming a chemical conversion film on a metal surface of a printed wiring board, alkylimidazole preflux, 5-methylbenzimidazole preflux, 2-mercaptobenzimidazole preflux, 2-alkyl are used. The publication describes a treatment method using a benzimidazole-based preflux, a 2-phenylimidazole-based preflux, a 2-phenylalkylbenzimidazole-based preflux, and a 2-alkylphenylbenzimidazole-based preflux.

[0003]

In recent years, the surface mounting method has been widely adopted as a method for soldering electronic components to a printed wiring board. Due to this surface mounting method, reflow of low melting point cream solder for temporary fixing of electronic parts, the printed wiring board is exposed to high temperatures frequently, and the heat resistance of the pre-flux used to maintain the solderability of the printed wiring board. Of the low melting point cream solder after the printed wiring board is exposed to a high temperature, the wettability, spreadability and solderability of the low melting point solder paste are required to be excellent in the performance of the preflux. However, the above-mentioned pre-flux treatment has a drawback that soldering is hindered when the chemical conversion film is exposed to high temperatures. Further, the stability of the liquid during use or storage was poor, and there was a defect that the crystallized product crystallized in the aqueous solution at low temperature.
Therefore, even after being exposed to high temperatures, the wettability of cream solder,
The development of stable water-soluble preflux with excellent solderability has been earnestly desired.

[0004]

Means for Solving the Problems As a result of intensive studies in view of such circumstances, the present inventor has found that the metal surface contains the compounds represented by (Chemical Formula 1) to (Chemical Formula 6) as an active ingredient. Corrosion resistance, heat resistance,
It was found that a chemical conversion film having excellent moisture resistance and chemical resistance was formed, and the present invention was completed. Typical compounds represented by (Chemical formula 1) to (Chemical formula 6) used in the practice of the present invention are 2- (1-phenylmethyl) -4-phenylimidazole and 2- (1-phenylmethyl) -4-phenyl. -5-methylimidazole, 2- (1-phenylmethyl) -4-benzylimidazole, 2- (1-phenylmethyl) -4-benzyl-5-methylimidazole,
2- (1-phenylmethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenylmethyl) -4- (2,4-dichlorophenylmethyl) -5
-Methylimidazole, 2- (1-phenylmethyl)-
4- (3,4-dichlorophenylmethyl) imidazole, 2- (1-phenylmethyl) -4- (3,4-dichlorophenylmethyl) -5-methylimidazole, 2-
(1-Phenylmethyl) -4- (4-bromophenylmethyl) imidazole, 2- (1-phenylmethyl) -4
-(4-Bromophenylmethyl) -5-methylimidazole, 2- (1-tolylmethyl) -4-phenylimidazole, 2- (1-tolylmethyl) -4-phenyl-5
-Methylimidazole, 2- (1-tolylmethyl) -4
-Benzylimidazole, 2- (1-tolylmethyl)-
4-benzyl-5-methylimidazole, 2- (1-tolylmethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-tolylmethyl) -4-
(2,4-Dichlorophenylmethyl) -5-methylimidazole, 2- (1-tolylmethyl) -4- (3,4-
Dichlorophenylmethyl) imidazole, 2- (1-tolylmethyl) -4- (3,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1-tolylmethyl) -4- (4-bromophenylmethyl) imidazole, 2- (1-Tolylmethyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2- (2-phenylethyl) -4-phenylimidazole, 2- (2
-Phenylethyl) -4-phenyl-5-methylimidazole, 2- (2-phenylethyl) -4-benzylimidazole, 2- (2-phenylethyl) -4-benzyl-5-methylimidazole, 2- (2 -Phenylethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (2-phenylethyl) -4- (2,4-
Dichlorophenylmethyl) -5-methylimidazole,
2- (2-phenylethyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (2-phenylethyl) -4- (3,4-dichlorophenylmethyl) -5
-Methylimidazole, 2- (2-phenylethyl)-
4- (4-bromophenylmethyl) imidazole, 2-
(2-Phenylethyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2- (2-tolylethyl) -4-phenylimidazole, 2- (2-tolylethyl) -4-phenyl-5-methyl Imidazole, 2
-(2-tolylethyl) -4-benzylimidazole,
2- (2-tolylethyl) -4-benzyl-5-methylimidazole, 2- (2-tolylethyl) -4- (2,2
4-dichlorophenylmethyl) imidazole, 2- (2
-Tolylethyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (2-tolylethyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (2-tolylethyl) -4- (3,4-
Dichlorophenylmethyl) -5-methylimidazole,
2- (2-tolylethyl) -4- (4-bromophenylmethyl) imidazole, 2- (2-tolylethyl) -4
-(4-Bromophenylmethyl) -5-methylimidazole, 2- (1-phenylethyl) -4-phenylimidazole, 2- (1-phenylethyl) -4-phenyl-5-methylimidazole, 2- (1 -Phenylethyl) -4-benzylimidazole, 2- (1-phenylethyl) -4-benzyl-5-methylimidazole, 2
-(1-Phenylethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenylethyl) -4- (2,4-dichlorophenylmethyl) -5-
Methylimidazole, 2- (1-phenylethyl) -4
-(3,4-dichlorophenylmethyl) imidazole,
2- (1-phenylethyl) -4- (3,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1
-Phenylethyl) -4- (4-bromophenylmethyl) imidazole, 2- (1-phenylethyl) -4-
(4-Bromophenylmethyl) -5-methylimidazole, 2- (1-phenylpropyl) -4-phenylimidazole, 2- (1-phenylpropyl) -4-phenyl-5-methylimidazole, 2- ( 1-phenylpropyl) -4-benzylimidazole, 2- (1-phenylpropyl) -4-benzyl-5-methylimidazole, 2- (1-phenylpropyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenylpropyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenylpropyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (1 -Phenylpropyl) -4-
(3,4-Dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenylpropyl) -4- (4-
Bromophenylmethyl) imidazole, 2- (1-phenylpropyl) -4- (4-bromophenylmethyl)-
5-methylimidazole, 2- (2-phenylpropyl) -4-phenylimidazole, 2- (2-phenylpropyl) -4-phenyl-5-methylimidazole,
2- (2-phenylpropyl) -4-benzylimidazole, 2- (2-phenylpropyl) -4-benzyl-
5-methylimidazole, 2- (2-phenylpropyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (2-phenylpropyl) -4- (2,4
-Dichlorophenylmethyl) -5-methylimidazole, 2- (2-phenylpropyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (2-phenylpropyl) -4- (3,4-dichlorophenyl) Methyl) -5-methylimidazole, 2- (2-phenylpropyl) -4- (4-bromophenylmethyl) imidazole, 2- (2-phenylpropyl) -4- (4-bromophenylmethyl) -5-methyl Imidazole, 2-
(3-phenylpropyl) -4-phenylimidazole, 2- (3-phenylpropyl) -4-phenyl-5
-Methylimidazole, 2- (3-phenylpropyl)
-4-Benzylimidazole, 2- (3-phenylpropyl) -4-benzyl-5-methylimidazole, 2-
(3-phenylpropyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (3-phenylpropyl) -4- (2,4-dichlorophenylmethyl) -5
-Methylimidazole, 2- (3-phenylpropyl)
-4- (3,4-dichlorophenylmethyl) imidazole, 2- (3-phenylpropyl) -4- (3,4-dichlorophenylmethyl) -5-methylimidazole, 2
-(3-phenylpropyl) -4- (4-bromophenylmethyl) imidazole, 2- (3-phenylpropyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2- (5-phenylpentyl) ) -4-Phenylimidazole, 2- (5-phenylpentyl)-
4-phenyl-5-methylimidazole, 2- (5-phenylpentyl) -4-benzylimidazole, 2-
(5-phenylpentyl) -4-benzyl-5-methylimidazole, 2- (5-phenylpentyl) -4-
(2,4-dichlorophenylmethyl) imidazole, 2
-(5-phenylpentyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (5
-Phenylpentyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (5-phenylpentyl) -4- (3,4-dichlorophenylmethyl) -5-
Methylimidazole, 2- (5-phenylpentyl)-
4- (4-bromophenylmethyl) imidazole, 2,
(5-Phenylpentyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2- (1-phenylmethyl) -4,5-diphenylimidazole, 2-
(1-phenylmethyl) -4,5-dibenzylimidazole, 2- (1-phenylmethyl) -4,5-di (2,2
4-dichlorophenyl) imidazole, 2- (1-phenylmethyl) -4,5-di (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenylmethyl)-
4,5-di (2,4-dibromophenyl) imidazole, 2- (1-phenylmethyl) -4,5-di (2,4)
-Dibromophenylmethyl) imidazole, 2- (1-
Phenylmethyl) -4,5-di (3,4-dichlorophenyl) imidazole, 2- (1-phenylmethyl) 4,
5-di (3,4-dichlorophenylmethyl) imidazole, 2- (1-phenylmethyl) -4,5- (3,4-
Dibromophenyl) imidazole, 2- (1-phenylmethyl) 4,5-di (3,4-dibromophenylmethyl) imidazole, 2- (2-phenylethyl) -4-
Phenylimidazole, 2- (2-phenylethyl)-
4-phenyl-5-methylimidazole, 2- (2-phenylethyl) -4-benzylimidazole, 2- (2
-Phenylethyl) -4-benzyl-5-methylimidazole, 2- (2-phenylethyl) -4- (2,4-
Dichlorophenylmethyl) imidazole, 2- (2-phenylethyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (2-phenylethyl) -4- (3,4-dichlorophenylmethyl)- 5
-Methylimidazole, 2- (2-phenylethyl)-
4- (4-bromophenylmethyl) imidazole, 2-
(2-Phenylethyl) -4- (4-bromophenylmethylimidazole, 2-naphthyl-4-phenylimidazole, 2-naphthyl-4-phenyl-5-methylimidazole, 2- (1-naphthylmethyl) -4- Phenyl-5-benzimidazole, 2- (1-naphthylmethyl) -4-benzyl-5-methylimidazole, 2-
(2-naphthylethyl) -4-phenyl-5-methylimidazole, 2- (2-naphthylethyl) -4-benzyl-5-methylimidazole, 2- (3-naphthylpropyl) -4-phenyl-5-methyl Imidazole, 2-
(3-naphthylpropyl) -4-benzyl-5-methylimidazole, 2- (4-naphthylbutyl) -4-phenyl-5-methylimidazole, 2- (4-naphthylbutyl) -4-benzyl-5-methyl Imidazole, 2-
(5-naphthylpentyl) -4-phenyl-5-methylimidazole, 2- (5-naphthylpentyl) -4-benzyl-5-methylimidazole, 2- (1-naphthylmethyl) -4,5-dibenzylimidazole , 2- (1
-Phenoxymethyl) -4-phenylimidazole, 2
-(1-phenoxymethyl) -4, phenyl-5-methylimidazole, 2- (1-phenoxymethyl) -4-
Benzylimidazole, 2- (1-phenoxymethyl)
-4-benzyl-5-methylimidazole, 2- (1-
Phenoxymethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenoxymethyl)
-4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenoxymethyl) -4-
(3,4-dichlorophenylmethyl) imidazole, 2
-(1-phenoxymethyl) -4- (3,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1
-Phenoxymethyl) -4- (4-bromophenylmethyl) imidazole, 2- (1-phenoxymethyl) -4
-(4-Bromophenylmethyl) -5-methylimidazole, 2- (1-phenoxyethyl) -4-phenylimidazole, 2- (1-phenoxyethyl) -4-phenyl-5-methylimidazole, 2- (1 -Phenoxyethyl) -4-benzylimidazole, 2- (1-phenoxyethyl) -4-benzyl-5-methylimidazole, 2- (1-phenoxyethyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2 -(1-phenoxyethyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenoxyethyl) -4- (3,4-dichlorophenylmethylimidazole, 2- (1-phenoxy) Ethyl) -4- (3,
4-dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenoxyethyl) -4- (4-bromophenylmethyl) imidazole, 2- (1-phenoxyethyl) -4- (4-bromophenylmethyl)- 5-methylimidazole, 2- (2-phenoxyethyl) -4
-Phenylimidazole, 2- (2-phenoxyethyl) -4-phenyl-5-methylimidazole, 2-
(2-phenoxyethyl) -4-benzylimidazole, 2- (2-phenoxyethyl) -4-benzyl-5
-Methylimidazole, 2- (2-phenoxyethyl)
-4- (2,4-dichlorophenylmethyl) imidazole, 2- (2-phenoxyethyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2
-(2-phenoxyethyl) -4- (3,4-dichlorophenylmethyl) imidazole, 2- (2-phenoxyethyl) -4- (3,4-dichlorophenylmethyl)-
5-methylimidazole, 2- (2-phenoxyethyl) -4- (4-bromophenylmethyl) imidazole, 2- (2-phenoxyethyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2 -(1
-Phenoxypropyl) -4-phenylimidazole,
2- (1-phenoxypropyl) -4-phenyl-5-
Methylimidazole, 2- (1-phenoxypropyl)
-4-Benzylimidazole, 2- (1-phenoxypropyl) -4-benzyl-5-methylimidazole, 2
-(1-phenoxypropyl) -4- (2,4-dichlorophenylmethyl) imidazole, 2- (1-phenoxypropyl) -4- (2,4-dichlorophenylmethyl) -5-methylimidazole, 2- (1- Phenoxypropyl) -4- (3,4-dichlorophenylmethyl)
Imidazole, 2- (1-phenoxypropyl) -4-
(3,4-Dichlorophenylmethyl) -5-methylimidazole, 2- (1-phenoxypropyl) -4- (4
-Bromophenylmethyl) imidazole, 2- (1-phenoxypropyl) -4- (4-bromophenylmethyl) -5-methylimidazole, 2- (2-methoxyphenyl) -4-benzyl-5-methylimidazole, 2
-(2-Ethoxyphenyl) -4-benzyl-5-methylimidazole, 2- (4-butoxyphenyl) -4-
Benzyl-5-methylimidazole, 2- (2-methoxyphenylmethyl) -4-benzyl-5-methylimidazole, 2- (4-ethoxyphenylmethyl) -4-benzyl-5-methylimidazole, 2- [2- (2-Methoxyphenyl) ethyl] -4-benzyl-5-methylimidazole, 2- [3- (4-methoxyphenyl) propyl] -4-benzyl-5-methylimidazole 2
-(2,4-dimethoxyphenyl) -4-benzyl-5
-Methylimidazole, 2- (3,4-diethoxyphenyl) -4-benzyl-5-methylimidazole, 2-
(4-chlorophenoxymethyl) -4-benzyl-5-
Methylimidazole, 2- [3- (2-methyl-4-chlorophenoxy) ethyl] -4-benzyl-5-methylimidazole, 2- (2,4-dichlorophenoxymethyl) -4-benzyl-5-methylimidazole , 2-
(2-methoxy-4-chlorophenyl) -4-benzyl-5-methylimidazole, 2- (1-phenoxymethyl) -4,5-dibenzylimidazole and the like. The compounds represented by (Chemical Formula 1) to (Chemical Formula 6) of the present invention are not particularly limited in use, but in addition to metal surface protective agents, they can be used as epoxy resin curing agents, dyeing assistants, organic synthetic intermediates and the like. It is useful. When the compounds represented by (Chemical formula 1) to (Chemical formula 6) of the present invention are used as a metal surface protective agent, they are used for solubilizing or emulsifying the compounds represented by (Chemical formula 1) to (Chemical formula 6). Examples of the organic acid used include acetic acid, iodoacetic acid, bromoacetic acid, dimethylacetic acid, diethylacetic acid, α-bromoacetic acid,
Chloroacetic acid, dichloroacetic acid, paranitrobenzoic acid, paratoluenesulfonic acid, picric acid, oxalic acid, formic acid, succinic acid, maleic acid, acrylic acid, fumaric acid, tartaric acid, malic acid, adipic acid, lactic acid, oleic acid, citric acid, Examples thereof include metasulfonic acid and sulfamic acid, and examples of the inorganic acid include hydrochloric acid, sulfuric acid, phosphorous acid, phosphoric acid and the like. Examples of the halogenated aromatic carboxylic acid include 3-bromo-4methylbenzoic acid, 4- (bromomethyl) phenylacetic acid, α-bromophenylacetic acid, α-bromotetradecanoic acid, 2-bromophenylacetic acid, 3-bromophenylacetic acid, 4-bromophenylacetic acid and the like. Examples of the halogenated fatty acid include bromoacetic acid, 3-bromo-2- (bromomethyl) propionic acid, 2-bromobutanoic acid, 4-bromobutanoic acid, 2-bromohexadecanoic acid, 2-bromohexanoic acid, 2-bromo-3-methylbutane. Acid, 2-bromo-2-methylpropionic acid, 2-bromooctanoic acid, 8-bromooctanoic acid, 2-bromopropionic acid, 3-bromopropionic acid, 2-bromopentanoic acid, 5-bromopentanoic acid, chloroacetic acid , Chlorobutyric acid, chloropropionic acid and the like.
Examples of metal ions include lithium, beryllium, potassium, magnesium, zinc acetate, zinc formate, zinc lactate, zinc citrate, zinc benzoate, zinc oxalate, zinc hydroxide, zinc bromide, zinc phosphate, zinc oxide, zinc chloride. , Lead acetate, lead hydroxide, lead bromide, lead iodide, lead oxalate, lead borate, ferrous chloride, ferric chloride, cuprous bromide, cupric bromide, cuprous iodide, Copper formate, nickel chloride, nickel acetate, cuprous chloride, cupric chloride, cuprous oxide, cupric oxide, copper hydroxide,
Metal compounds such as copper phosphate, copper carbonate, copper acetate, and copper sulfate. At least one selected from any of the above groups and one or two compounds represented by (Chemical Formula 1) to (Chemical Formula 6)
Used as an aqueous solution that is a mixture of more than one type. It should be noted that adding a substance having a buffering action such as aqueous ammonia or amines to the treatment liquid is effective not only for enhancing the stability of PH of the aqueous solution but also for accelerating the film formation rate. In addition, various additives which have been conventionally used as surface treatment agents and the like may be added as necessary. In the practice of the present invention, the compounds represented by (Chemical formula 1) to (Chemical formula 6) and organic acids, metal compounds, halogenated aromatic carboxylic acids,
When it becomes difficult to dissolve the halogenated fatty acid, water-soluble solvents such as methanol, ethanol, isopropyl alcohol, butanol, and acetone can be used individually, or they can be mixed and used at any ratio. Is. It is also effective to add a surfactant and an emulsifying dispersant. Corrosion resistance, heat resistance, and chemical resistance of the chemical conversion coating are obtained by contacting with an aqueous solution containing the compounds represented by (Chemical formula 1) to (Chemical formula 6), an organic acid, and a metal compound used in the method of the present invention. Property, solder wettability, and solder spreadability can be further enhanced. It is also possible to improve the heat resistance by applying a thermoplastic resin after forming the chemical conversion film. In order to apply a rust-preventive chemical conversion coating and a chemical resistance chemical conversion coating to the metal surface with the metal surface protective agent of the present invention, the metal and the treatment liquid are brought into contact with each other. As a method of contacting, a method of dipping, spraying or coating is used. It is suitable that the temperature of the treatment liquid to be brought into contact is in the temperature range of 0 to 100 ° C. and the immersion time is several seconds to several tens of minutes.

[0005]

By incorporating an alkoxy group, a phenoxy group or an alkylene group at the 2-position of the imidazole ring, crystals of an aqueous solution of this compound are extremely unlikely to crystallize and the stability during use or storage is significantly improved. Also, the heat resistance is remarkably improved. According to the above-mentioned treatment method, a rust-preventive chemical conversion film mainly composed of (Chemical formula 1) to (Chemical formula 6), which is effective for surfaces of metals such as copper, copper alloys, solders, electroless solders, nickel, silver and zinc , A chemical resistant conversion coating is formed. These chemical conversion coatings are water-repellent, have excellent moisture resistance, heat resistance, and chemical resistance, and protect the metal surface for a long period of time, as well as the wettability, spreadability, solder rise after reflow, and wettability of low melting point cream solder. It is good. In addition, it is possible to manufacture a printed wiring board excellent in terms of work environment and safety.

[0006]

Example 1 Ammonia water was added to an aqueous solution containing 0.5 wt% of the compounds (Chemical formula 1) to (Chemical formula 6) described in Table 1, formic acid, diethyl acetic acid, cupric bromide, ion-exchanged water and the like. PH
Each kind of adjusted aqueous solution was prepared, put into a 100 ml container, and the liquid temperature was heated to 40 ° C. On the other hand, 1 cm x 5 c
m × 0.3mm copper plate, 1cm × 5cm × 0.3mm
The sample piece of the nickel plate was prepared, and then the surface was washed and immersed for 60 seconds in each type of 0.5 wt% aqueous solution containing the compound represented by the above (Chemical formula 1) to (Chemical formula 6) as an active ingredient. Then, after washing with water, the sample pieces (1) to (1) were placed in a hot air dryer, heated at 250 ° C. for 5 minutes, immersed in post flux, and the wetting time was measured using a solder wettability tester. Moisture resistant (MIL-STD-2
02F-M-106D) The treated test piece was immersed in post flux and the wetting time was measured using a solder wettability tester. (3) Five kinds of 0.5 wt% aqueous solutions containing the compounds shown in (Chemical formula 1) to (Chemical formula 6) as active ingredients
The stability of the liquid was confirmed by putting it in a refrigerator at 10 ° C for 10 days. The above test results are shown in Table 1.

[Table 1]

[0007]

Example 2 Aqueous solution containing 0.5 wt% of the compounds (Chemical formula 1) to (Chemical formula 6) described in Table 1, formic acid, diethyl acetic acid, cupric bromide, isopropyl alcohol, ion-exchanged water and the like in aqueous ammonia. Was added to prepare each type of aqueous solution having a pH adjusted, which was placed in a 100 ml container and heated to a liquid temperature of 40 ° C. On the other hand, 1 cm x 5 cm x 0.3 mm copper plate, 1
cm × 5 cm × 0.3 mm sample piece of nickel plate was prepared, and then the surface was washed, and 0.5 wt% of each kind containing the compound shown in (Chemical formula 1) to (Chemical formula 6) as an active ingredient.
It was immersed in the aqueous solution for 60 seconds. After washing with water,
Put the sample pieces of (1) to 5 in a hot air dryer at 250 ° C.
After heating for one minute, the sample was immersed in post flux and the wetting time was measured using a solder wettability tester. The test pieces after the moisture resistance (MIL-STD-202F-M-106D) treatment of the sample pieces of (2) to (4) were immersed in post flux and the wetting time was measured using a solder wettability tester. (3) Each type of 0.5 wt% aqueous solution containing the compound represented by the above (Chemical Formula 1) to (Chemical Formula 4) as an active ingredient was placed in a refrigerator at 5 ° C. for 10 days to confirm the stability of the liquid. The above test results are shown in Table 1.

[0008]

Comparative Example 1 2-phenyl-4-benzyl-5-methylimidazole 0.40 wt%, acetic acid 2.0 wt%, cupric acetate 0.063 wt% and ammonium bromide 0.0
An aqueous solution containing 25 wt% was prepared, put in a 100 ml container, and the liquid temperature was heated to 50 ° C. On the other hand, 1 cm x 5 c
m × 0.3mm copper plate, 1cm × 5cm × 0.3mm
Of nickel plate was prepared, then the surface was washed and immersed in the aqueous solution for 60 seconds. After washing with water,
Put the sample pieces of (1) to 5 in a hot air dryer at 250 ° C.
After heating for one minute, the sample was immersed in post flux and the wetting time was measured using a solder wettability tester. The test pieces after the moisture resistance (MIL-STD-202F-M-106D) treatment of the sample pieces of (2) to (4) were immersed in post flux and the wetting time was measured using a solder wettability tester. (3) The above aqueous solution was placed in a refrigerator at 5 ° C for 10 days to confirm the stability of the solution. The above test results are shown in Table 1.

[0009]

Comparative Example 2 2-phenyl imidazole 1.0 wt
%, Acetic acid 2.0 wt%, cupric chloride 0.05 wt% and ammonium bromide were prepared and put in a 100 ml container and heated to 50 ° C. On the other hand, 1 cm x
5 cm x 0.3 mm copper plate, 1 cm x 5 cm x 0.3
A sample piece of a mm nickel plate was prepared, and then the surface was washed and immersed in the aqueous solution for 60 seconds. Then, after washing with water, the sample pieces of (1) to
After being heated for 5 minutes, the sample was immersed in post flux and the wetting time was measured using a solder wettability tester. Moisture resistance (MIL-STD-202F-M-106
D) The treated test piece was dipped in post flux and the wetting time was measured using a solder wettability tester. (3) The above aqueous solution was placed in a refrigerator at 5 ° C for 10 days to confirm the stability of the solution. The above test results are shown in Table 1.

[0010]

Comparative Example 3 2-Phenyl-benzimidazole 1.0
wt%, acetic acid 2.5 wt%, cupric chloride 0.05 wt%
And make an aqueous solution containing ammonium bromide, 100m
The solution was heated to 50 ° C. in a 1-liter container. On the other hand, 1c
mx 5 cm x 0.3 mm copper plate, 1 cm x 5 cm x
A sample piece of a 0.3 mm nickel plate was prepared, and then the surface was washed and immersed in the aqueous solution for 60 seconds. Then, after washing with water, the sample pieces of (1) to
After heating at 0 ° C. for 5 minutes, it was immersed in post flux and the wetting time was measured using a solder wettability tester. (2) ~
Moisture resistance (MIL-STD-202F-M-10
6D) The treated test piece was immersed in post flux and the wetting time was measured using a solder wettability tester. (3)
The above aqueous solution was placed in a refrigerator at 5 ° C. for 10 days to confirm the stability of the solution. The above test results are shown in Table 1.

[0011]

Comparative Example 4 2-p-nonylphenylimidazole 1.
0wt%, glacial acetic acid 6.0wt%, cupric acetate 0.05w
make an aqueous solution containing t% and ammonium bromide, and
The solution was placed in a 0 ml container and heated to 50 ° C. On the other hand,
1 cm x 5 cm x 0.3 mm copper plate, 1 cm x 5 cm
A sample piece of a nickel plate having a size of 0.3 mm was prepared, and then the surface was washed and immersed in the aqueous solution for 60 seconds. Then, after washing with water, put the sample pieces of (1) to 2 in a hot air dryer.
After heating at 50 ° C. for 5 minutes, it was immersed in post flux and the wetting time was measured using a solder wettability tester. (2) ~
Moisture resistant (MIL-STD-202F-M-1
06D) The treated test piece was immersed in post flux and the wetting time was measured using a solder wettability tester.
(3) The above aqueous solution was placed in a refrigerator at 5 ° C for 10 days to confirm the stability of the solution. The above test results are shown in Table 1.

[0012]

The compound of the present invention is soaked in a very stable aqueous solution to form a chemical conversion coating film having excellent rust resistance, moisture resistance, heat resistance and chemical resistance on the metal surface for a long period of time. Especially for surface mounting of a printed wiring board that is not only protected, but also has good wettability and spreadability of low melting point cream solder, solderability after reflow, good wettability, and excellent work environment and safety. It is possible to exert a remarkable effect.

Claims (5)

[Claims] 1. A compound represented by (Chemical formula 1) to (Chemical formula 6): Embedded image Embedded image [Chemical 4] Embedded image [Chemical 6] 2. A metal surface protective agent comprising the compounds represented by (Chemical formula 1) to (Chemical formula 6) as an active ingredient. 3. A surface protective agent for metal and a method for using the same, which comprises contacting with an aqueous solution containing the compounds represented by (Chemical formula 1) to (Chemical formula 6), an organic acid and a metal compound. 4. A method for producing a printed wiring board, which comprises applying a soldering treatment after applying a metal surface protective agent. 5. An infrared reflow process, a near infrared reflow process, a far infrared reflow process, and nitrogen which are heated in air or a nitrogen atmosphere after applying the metal surface protective agent represented by (Chemical formula 1) to (Chemical formula 6) on the metal surface. A method for manufacturing a printed wiring board, comprising performing reflow and vapor reflow processing.