KR20110073421A - Surface treatment agents for copper or copper alloys and uses thereof - Google Patents

Abstract

R은 수소 원자 또는 알킬기를 나타내고, X₁ 및 X₂는 동일하거나 상이하고 염소 원자 또는 브롬 원자를 나타내며; m 및 n은 0 내지 3의 정수를 나타내고, m 또는 n 중 적어도 하나는 1 이상이다. 상기 표면 처리제는 표면 처리방법, 인쇄 배선 기판 제작 및 솔더링 방법에도 사용된다.In the surface treating agent for copper or copper alloy containing the imidazole compound represented by Formula (I):

R represents a hydrogen atom or an alkyl group, X ₁ and X ₂ are the same or different and represent a chlorine atom or bromine atom; m and n represent the integer of 0-3, and at least one of m or n is one or more. The surface treatment agent is also used for the surface treatment method, printed wiring board fabrication and soldering method.

Description

SURFACE TREATING AGENT FOR COPPER OR COPPER ALLOY AND USE THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to surface treatment agents used during soldering of electronic components and the like to copper or copper alloys of printed printed wiring boards and their use.

In recent years, high-density surface mounting technology has been widely adopted as a method of mounting printed wiring boards. Such surface mount technologies include, among others, double-sided surface mount technology, in which chip-type components are joined using solder paste, and surface-mount technology of chip-type components using solder paste; It is classified as a mixed mounting technique, which is a combination of through-hole mounting techniques of discontinuous parts. In either mounting process, the printed wiring board is subjected to two or more soldering steps, thus exposing it to high temperatures resulting in severe thermal history.

As a result, the formation of an oxide film is promoted by heating the surface of the copper or copper alloys (hereinafter, simply referred to as copper) constituting the circuit portion of the printed piping board so that the surface of the circuit portion cannot maintain good solderability. .

In order to protect the copper circuit portion of the printed wiring board from air oxidation, a chemical layer is generally formed on the surface of the circuit portion using the surface treating agent. However, even after the copper circuit portion has multiple cycles of thermal history, it is desired to maintain good solderability by preventing the chemical layer from degrading (ie, degrading) to protect the copper circuit portion.

Tin-lead alloy eutectic solders have been conventionally used to mount electronic components on printed wiring boards and the like. Recently, however, there is a concern that lead contained in the solder alloy has a harmful effect on the human body, and thus, there is a desire to use lead-free solder.

Therefore, various lead-free solders are considered. For example, lead-free solder has been proposed in which one or more metals such as silver, zinc, bismuth, indium, antimony, copper, and the like are added to the base metal of tin.

The conventionally used tin-lead process solder is particularly excellent in wettability on the surface of a substrate which is copper, and thus strongly adheres to copper and has high reliability.

In contrast, lead-free solders are inferior to conventionally used tin-lead solders in wettability on copper substrates, resulting in poor solder strength and poor solder strength due to voids and other bonding defects.

Therefore, when using lead-free solder, it is necessary to select a flux suitable for the use of a lead-free solder and a solder alloy having excellent solderability. In addition, the surface treatment agent used to prevent oxidation on the surface of copper or copper alloy is required to have a function of improving the wettability and solderability of the lead-free solder.

Many lead-free solders have a high melting point and a soldering temperature of about 20 to about 50 ° C. higher than the soldering temperatures of conventionally used tin-lead process solders. Therefore, the surface treatment agent used in the soldering process with lead-free solder should be characterized by the ability to form a chemical layer with good heat resistance.

As the active ingredient of such surface treating agents, various imidazole compounds have been proposed. For example, Patent Document 1 discloses 2-alkylimidazole compounds such as 2-undecylimidazole; Patent Document 2 discloses 2-arylimidazole compounds such as 2-phenylimidazole and 2-phenyl-4-methylimidazole. To start; Patent Document 3 discloses 2-alkylbenzimidazole compounds such as 2-nonylbenzimidazole; Patent Document 4 discloses 2-aralkylbenzimidazole such as 2- (4-chlorophenylmethyl) benzimidazole; Patent Document 5 discloses 2- (4-chlorophenylmethyl) imidazole (2- (4-chlorophenylmethyl) imidazole) and 2- (2,4-dichlorophenylmethyl) -4,5-diphenylimidazole (2 2-aralkylimidazole compounds such as-(2,4-dichlorophenylmethyl) -4,5-diphenylimidazole) are disclosed.

However, when a surface treating agent containing such an imidazole compound is used, the heat resistance of the chemical layer formed on the copper surface is not yet satisfactory. Further, in soldering, solder wettability is not sufficient, and good solderability cannot be obtained. In particular, when performing soldering using lead-free solder instead of process solder, it was difficult to actually use the surface treatment agent.

JP-B-46-17046 JP-A-4-206681 JP-A-5-25407 JP-A-5-186888 JP-A-7-243054

In view of the above problems, the present invention has been completed. SUMMARY OF THE INVENTION An object of the present invention is to form a chemical layer having excellent heat resistance on the surface of a copper or copper alloy constituting a circuit portion such as a printed wiring board when mounting an electronic component or the like on a printed wiring board using solder and simultaneously It is to provide a surface treatment agent and a surface treatment method to improve the wettability to the solder and to improve the solderability.

Another object of the present invention is to provide a printed wiring board formed by contacting a surface of a copper or a copper alloy constituting a copper circuit portion with the surface treatment agent, wherein the surface of the copper or copper alloy is formed on the surface treatment agent. The present invention provides a soldering method for performing soldering using lead-free solder after contacting with the.

In order to solve the above problems, the inventors have conducted extensive and intensive investigation. As a result, by treating the printed wiring board having the copper circuit portion with a surface treatment agent containing an imidazole compound represented by formula (I), a chemical having excellent heat resistance, that is, capable of withstanding the soldering temperature of the lead-free solder It has been found that a layer can be formed on the surface of the copper circuit portion and at the same time improve the wettability of the solder on the surface of the copper or copper alloy when soldering with lead-free solder, thereby obtaining good solderability and thus completing the present invention. .

That is, the present invention includes the following aspects in its broadest configuration:

(1) Surface treatment agent for copper or copper alloy containing the imidazole compound represented by Formula (I):

Wherein R represents a hydrogen atom or an alkyl group, X ₁ and X ₂ are the same or different and represent a chlorine atom or bromine atom; m and n represent the integer of 0-3, and at least one of m or n is one or more.

(2) In the surface treatment agent according to (1), m and n are each one or more.

(3) In the surface treatment agent according to the above (1), at least one of m or n is two or more.

(4) A surface treatment method of copper or copper alloy, comprising contacting the surface of copper or copper alloy with the surface treating agent according to any one of (1) to (3).

(5) A printed wiring board comprising copper or a copper alloy constituting a copper circuit portion, wherein the surface of the copper or the alloy is in contact with the surface treatment agent according to any one of (1) to (3).

(6) A method of soldering comprising contacting a surface of copper or a copper alloy with a surface treatment agent according to any one of (1) to (3) above and then performing soldering with lead-free solder.

The surface treating agent according to the present invention can not only form a chemical layer having excellent heat resistance on the surface of the copper or copper alloy constituting a circuit portion such as a printed wiring board, but also greatly improve the wettability of the lead-free solder on the target surface. To improve and provide good solderability.

In addition, the soldering method according to the present invention is useful from the viewpoint of environmental protection because it enables the use of a solder containing no lead which is a hazardous metal.

The imidazole compound used in the present invention is formula (I), that is, the benzyl group is bonded to the 2-position of the imidazole ring (hereinafter simply referred to as benzyl group), and the phenyl group is placed at the 4 (5) -position of the imidazole ring. Are bound (hereinafter simply referred to as phenyl groups), and at least one of the benzyl group or the benzene ring of the phenyl group is one or more chlorine atom (s) and / or bromine atom (s) (hereafter chlorine atom and bromine atom) Is represented by an imidazole compound having a basic skeleton which is collectively substituted with a halogen atom):

Here, R, X ₁ , X ₂ , m and n in the above formula are the same as described above.

Such imidazole compounds can be classified into the following categories (A) to (B) based on halogen (ie chlorine and / or bromine) substitutions:

(A) imidazole compounds in which the hydrogen atom in only one of the benzyl group or the phenyl group is substituted with one halogen atom;

(B) imidazole compounds in which hydrogen atoms in both benzyl and phenyl groups are each substituted with one halogen atom;

(C) imidazole compounds in which hydrogen atoms in only one of the benzyl group or the phenyl group are substituted with two or more halogen atoms;

(D) imidazole compounds in which hydrogen atoms in either the benzyl group or the phenyl group are substituted with two or more halogen atoms and hydrogen atoms in the other place are substituted with one halogen atom, and

(E) Imidazole compounds in which hydrogen atoms in both benzyl and phenyl groups are each substituted with two or more halogen atoms.

According to the findings obtained by the inventors, a chemical layer is formed on the surface of copper or copper alloy using a surface treatment agent containing one of the imidazole compounds of the above categories (A) to (E), and lead-free solder is formed. When soldering was performed using, solderability was improved in the order of (A) <(B) <(C) to (E). That is, the surface treating agent containing the imidazole compound of (B) is used compared with the solder joint when the chemical layer is formed on the copper surface using the surface treating agent containing the imidazole compound of (A). This results in better solderability when a chemical layer is formed on the copper surface. Similarly, compared with the case of the imidazole compound of said (B), in the case of the imidazole compound of said (C), it is excellent in solderability. In addition, almost the same solderability was obtained when a chemical layer was formed on the copper surface using the surface treating agent containing any one of the above (C), (D) and (E).

According to the above findings, for imidazoles suitable for carrying out the invention, it is preferred if both m and n are at least 1, as compared with the case where at least one of m or n is at least 1, and at least one of m or n is 2 The case above is more preferable.

R in formula (I) is a hydrogen atom or an alkyl group, preferably, said alkyl group is a linear or branched chain saturated aliphatic group having 1 to 8 carbon atoms. Examples of such alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group and octyl group.

Imidazoles Used in the Practice of the Invention The synthesis method shown in the following reaction scheme can be employed. In this regard, a phenylacetamidine hydrochloride compound may be suitably used as the phenylacetamidine compound.

Here, R, X ₁ , X ₂ , m and n are the same as described above, and X ₃ represents a chlorine atom, bromine atom or iodine atom.

Examples of imidazole compounds represented by formula (I) employed in carrying out the invention, where R is a hydrogen atom, include the following:

2-benzyl-4- (2-chlorophenyl) imidazole,

2-benzyl-4- (3-chlorophenyl) imidazole,

2-benzyl-4- (4-chlorophenyl) imidazole,

2-benzyl-4- (2-bromophenyl) imidazole,

2-benzyl-4- (3-bromophenyl) imidazole,

2-benzyl-4- (4-bromophenyl) imidazole,

2-benzyl-4- (2,3-dichlorophenyl) imidazole,

2-benzyl-4- (2,4-dichlorophenyl) imidazole,

2-benzyl-4- (2,5-dichlorophenyl) imidazole,

2-benzyl-4- (2,6-dichlorophenyl) imidazole,

2-benzyl-4- (3,4-dichlorophenyl) imidazole,

2-benzyl-4- (3,5-dichlorophenyl) imidazole,

2-benzyl-4- (2,4-dibromophenyl) imidazole,

2-benzyl-4- (2,5-dibromophenyl) imidazole,

2-benzyl-4- (2,4,5-trichlorophenyl) imidazole,

2-benzyl-4- (3,4,5-trichlorophenyl) imidazole,

2-benzyl-4- (2,4,5-tribromophenyl) imidazole,

2- (2-chlorobenzyl) -4-phenylimidazole,

2- (3-chlorobenzyl) -4-phenylimidazole,

2- (4-chlorobenzyl) -4-phenylimidazole,

2- (2-bromobenzyl) -4-phenylimidazole,

2- (3-bromobenzyl) -4-phenylimidazole,

2- (4-bromobenzyl) -4-phenylimidazole,

2- (2-chlorobenzyl) -4- (2-chlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (4-chlorophenyl) imidazole,

2-4- (chlorobenzyl) -4- (2-chlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (4-chlorophenyl) imidazole,

4- (4-bromophenyl) -2- (4-chlorobenzyl) imidazole,

2- (4-bromobenzyl) -4- (2-chlorophenyl) imidazole,

2- (4- (bromobenzyl) -4- (4-chlorophenyl) imidazole,

2- (4-bromobenzyl) -4- (4-bromophenyl) imidazole,

2- (2-chlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2-chlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (3-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (3-chlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,4-dibromophenyl) imidazole,

2- (2-bromobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2-bromobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2-bromobenzyl) -4- (2,5-dibromophenyl) imidazole,

2- (2-chlorobenzyl) -4- (2,4,5-trichlorophenyl) imidazole,

2- (4-chlorobenzyl) -4- (2,4,5-tribromophenyl) imidazole,

2- (4-bromobenzyl) -4- (2,4,5-trichlorophenyl) imidazole,

2- (2-bromobenzyl) -4- (2,4,6-tribromophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4-phenylimidazole,

2- (2,4-dichlorobenzyl) -4-phenylimidazole,

2- (2,5-dichlorobenzyl) -4-phenylimidazole,

2- (2,6-dichlorobenzyl) -4-phenylimidazole,

2- (2,6-dichlorobenzyl) -4-phenylimidazole,

2- (3,4-dichlorobenzyl) -4-phenylimidazole,

2- (3,5-dichlorobenzyl) -4-phenylimidazole,

2- (2,4-dibromobenzyl) -4-phenylimidazole,

4- (2-chlorophenyl) -2- (2,3-dichlorobenzyl) imidazole,

4- (2-chlorophenyl) -2- (2,4-dichlorobenzyl) imidazole,

4- (2-chlorophenyl) -2- (2,5-dichlorobenzyl) imidazole,

4- (2-chlorophenyl) -2- (2,6-dichlorobenzyl) imidazole,

4- (2-chlorophenyl) -2- (3,4-dichlorobenzyl) imidazole,

4- (2-chlorophenyl) -2- (3,5-dichlorobenzyl) imidazole,

4- (3-chlorophenyl) -2- (2,4-dichlorobenzyl) imidazole,

4- (3-chlorophenyl) -2- (2,6-dichlorobenzyl) imidazole,

4- (3-chlorophenyl) -2- (3,4-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,3-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,4-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,5-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,6-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (3,4-dichlorobenzyl) imidazole

4- (4-chlorophenyl) -2- (3,5-dichlorobenzyl) imidazole,

4- (2-bromophenyl) -2- (2,4-dichlorobenzyl) imidazole,

4- (2-bromophenyl) -2- (3,4-dichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,5-dibromobenzyl) imidazole,

4- (2-bromophenyl) -2- (2,5-dibromobenzyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (2,3-dichlorophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (2,4-dichlorophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (2,5-dichlorophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (2,6-dichlorophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2,3-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (2,5-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (2,6-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

2- (3,5-dichlorobenzyl) -4- (3,5-dichlorophenyl) imidazole,

4- (2,5-dibromophenyl) -2- (2,4-dichlorobenzyl) imidazole,

4- (2,5-dibromophenyl) -2- (3,4-dichlorobenzyl) imidazole,

2- (2,5-dibromobenzyl) -4- (3,4-dichlorophenyl) imidazole,

2- (2,4-dibromobenzyl) -4- (3,4-dibromophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (3,4,5-trichlorophenyl) imidazole,

2- (2,4-dichlorobenzyl) -4- (2,4,6-tribromophenyl) imidazole,

2- (2,4-dibromobenzyl) -4- (3,4,5-trichlorophenyl) imidazole,

2- (2,4-dibromobenzyl) -4- (2,4,5-trichlorophenyl) imidazole,

4-phenyl-2- (3,4,5-trichlorobenzyl) imidazole,

4-phenyl-2- (2,4,5-tribromobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,3,6-trichlorobenzyl) imidazole,

4- (2-bromophenyl) -2- (3,4,5-trichlorobenzyl) imidazole,

4- (4-chlorophenyl) -2- (2,3,5-tribromobenzyl) imidazole,

4- (4-bromophenyl) -2- (2,4,6-tribromobenzyl) imidazole,

4- (2,4-dichlorophenyl) -2- (3,4,5-trichlorobenzyl) imidazole,

4- (2,4-dibromophenyl) -2- (3,4,5-trichlorobenzyl) imidazole,

4- (3,4-dichlorophenyl) -2- (2,4,5-tribromobenzyl) imidazole,

4- (2,5-dibromophenyl) -2- (2,3,5-tribromobenzyl) imidazole,

2- (3,4,5-trichlorobenzyl) -4- (2,4,5-trichlorophenyl) -imidazole,

4- (2,4,5-tribromophenyl) -2- (3,4,5-trichlorobenzyl) -imidazole,

2- (2,4,6-tribromobenzyl) -4- (2,4,5-trichlorophenyl) -imidazole, and

2- (2,4,6-tribromobenzyl) -4- (2,4,6-tribromophenyl) -imidazole.

Likewise, examples where R is a methyl group include the following:

2-benzyl-4- (2-chlorophenyl) -5-methylimidazole,

2-benzyl-4- (3-chlorophenyl) -5-methylimidazole,

2-benzyl-4- (4-chlorophenyl) -5-methylimidazole,

2-benzyl-4- (2-bromophenyl) -5-methylimidazole,

2-benzyl-4- (3-bromophenyl) -5-methylimidazole,

2-benzyl-4- (4-bromophenyl) -5-methylimidazole,

2-benzyl-4- (2,3-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (2,4-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (2,5-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (2,6-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (3,5-dichlorophenyl) -5-methylimidazole,

2-benzyl-4- (2,4-dibromophenyl) -5-methylimidazole,

2-benzyl-4- (2,5-dibromophenyl) -5-methylimidazole,

2-benzyl-5-methyl-4- (2,4,5-trichlorophenyl) imidazole,

2-benzyl-5-methyl-4- (3,4,5-trichlorophenyl) imidazole,

2-benzyl-5-methyl-4- (2,4,5-tribromophenyl) imidazole,

2- (2-chlorobenzyl) -5-methyl-4-phenylimidazole,

2- (3-chlorobenzyl) -5-methyl-4-phenylimidazole,

2- (4-chlorobenzyl) -5-methyl-4-phenylimidazole,

2- (2-bromobenzyl) -5-methyl-4-phenylimidazole,

2- (3-bromobenzyl) -5-methyl-4-phenylimidazole,

2- (4-bromobenzyl) -5-methyl-4-phenylimidazole,

2- (2-chlorobenzyl) -4- (2-chlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2-chlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole,

4- (4-bromophenyl) -2- (2-chlorobenzyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (2-chlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (4-chlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (4-bromophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (3-chlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (3-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (2,4-dibromophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -5-methyl-4- (2,4,5-trichlorophenyl) -imidazole,

2- (4-chlorobenzyl) -5-methyl-4- (2,4,5-trichlorophenyl) -imidazole,

2- (4-bromobenzyl) -5-methyl-4- (2,4,5-trichlorophenyl) -imidazole,

2- (2-bromobenzyl) -5-methyl-4- (2,4,6-tribromophenyl) -imidazole,

2- (2,3-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (2,4-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (2,5-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (2,6-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (3,4-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (3,5-dichlorobenzyl) -5-methyl-4-phenylimidazole,

2- (2,4-dibromobenzyl) -5-methyl-4-phenylimidazole,

4- (2-chlorophenyl) -2- (2,3-dichlorobenzyl) -5-methylimidazole,

4- (2-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole,

4- (2-chlorophenyl) -2- (2,5-dichlorobenzyl) -5-methylimidazole,

4- (2-chlorophenyl) -2- (2,6-dichlorobenzyl) -5-methylimidazole,

4- (2-chlorophenyl) -2- (3,4-dichlorobenzyl) -5-methylimidazole,

4- (2-chlorophenyl) -2- (3,5-dichlorobenzyl) -5-methylimidazole,

4- (3-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole,

4- (3-chlorophenyl) -2- (2,6-dichlorobenzyl) -5-methylimidazole,

4- (3-chlorophenyl) -2- (3,4-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (2,3-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (2,5-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (2,6-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (3,4-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (3,5-dichlorobenzyl) -5-methylimidazole,

4- (2-bromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole,

4- (4-bromophenyl) -2- (3,4-dichlorobenzyl) -5-methylimidazole,

4- (4-chlorophenyl) -2- (2,5-dibromobenzyl) -5-methylimidazole,

4- (4-bromophenyl) -2- (2,5-dibromobenzyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (2,3-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (2,5-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (2,6-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (3,5-dichlorophenyl) -5-methylimidazole,

4- (2,5-dibromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole,

4- (2,5-dibromophenyl) -2- (3,4-dichlorobenzyl) -5-methylimidazole,

2- (2,5-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,4-dibromobenzyl) -4- (3,4-dibromophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -5-methyl-4- (3,4,5-trichlorophenyl) imidazole,

2- (3,4-dichlorobenzyl) -5-methyl-4- (2,4,6-tribromophenyl) imidazole,

2- (2,4-dibromobenzyl) -5-methyl-4- (3,4,5-trichlorophenyl) imidazole,

2- (2,4-dibromobenzyl) -5-methyl-4- (2,4,5-tribromophenyl) imidazole,

5-methyl-4-phenyl-2- (3,4,5-trichlorobenzyl) imidazole,

5-methyl-4-phenyl-2- (2,4,5-tribromobenzyl) imidazole,

4- (4-chlorophenyl) -5-methyl-2- (2,3,6-trichlorobenzyl) imidazole,

4- (4-bromophenyl) -5-methyl-2- (3,4,5-trichlorobenzyl) imidazole,

4- (4-chlorophenyl) -5-methyl-2- (2,3,5-tribromobenzyl) imidazole,

4- (4-bromophenyl) -5-methyl-2- (2,4,6-tribromobenzyl) imidazole,

4- (2,4-dichlorophenyl) -5-methyl-2- (3,4,5-trichlorobenzyl) imidazole,

4- (2,4-dibromophenyl) -5-methyl-2- (3,4,5-trichlorobenzyl) imidazole,

4- (3,4-dichlorophenyl) -5-methyl-2- (2,4,5-tribromobenzyl) imidazole,

4- (2,5-dibromophenyl) -5-methyl-2- (2,3,5-tribromobenzyl) imidazole,

5-methyl-2- (3,4,5-trichlorobenzyl) -4- (2,4,5-trichlorophenyl) imidazole,

5-methyl-4- (2,4,5-tribromophenyl) -2- (3,4,5-trichlorobenzyl) imidazole,

5-methyl-2- (2,4,6-tribromobenzyl) -4- (2,4,5-trichlorophenyl) imidazole, and

5-methyl-2- (2,4,6-tribromobenzyl) -4- (2,4,6-tribromophenyl) imidazole.

The imidazole compound is used as an active ingredient of a surface treating agent prepared by dissolving in water. The imidazole compound may be contained, for example, in a ratio of 0.01 to 10% by weight and preferably 0.1 to 5% by weight in the surface treating agent. When the content of the imidazole compound is less than 0.01% by weight, the film thickness of the chemical layer formed on the copper surface may be so thin that oxidation of the copper surface may not be sufficiently prevented. On the other hand, if it exceeds 10% by weight, there is a concern that the imidazole compound in the surface treatment agent may not be completely dissolved or may be undesirable because the compound may be reprecipitated even after being completely dissolved.

In carrying out the present invention, by chance, only one suitable kind of imidazole compounds represented by formula (I) can be used, but it is also possible to use a combination of the above mentioned different kinds of imidazole compounds.

In carrying out the present invention, in the case of dissolving the imidazole compound in water (aqueous solution formation), an organic or inorganic acid may be generally used as an acid, but a small amount of an organic solvent may be used simultaneously. Representative examples of organic acids used in this case are formic acid, acetic acid, propionic acid, butyric acid, glyoxylic acid, pyruvic acid, acetoacetic acid, levulinic acid, heptanoic acid, caprylic acid, capric acid, lauric acid, glycolic acid, glycolic acid. Seric acid, lactic acid, acrylic acid, methoxyacetic acid, ethoxyacetic acid, propoxyacetic acid, butoxyacetic acid, 2- (2-methoxyethoxy) acetic acid (2- (2-methoxyethoxy) acetic acid), 2- [2- (2-ethoxyethoxy) ethoxy] acetic acid (2- [2- (2-ethoxyethoxy) ethoxy] acetic acid), 2- {2 -[2- (2-ethoxyethoxy) ethoxy] ethoxy} acetic acid, 3-methoxypropionic acid, 3-ethoxypropionic acid, 3-propoxypropionic acid, 3-butoxypropionic acid, benzoic acid, p-nitrobenzoic acid , p-toluenesulfonic acid, salicylic acid, picric acid, oxalic acid, succinic acid, maleic acid, fumaric acid, tartaric acid and adipic acid; And examples of the inorganic acid include hydrochloric acid, phosphoric acid, sulfuric acid and nitric acid. Such acids may be added in a proportion of 0.1 to 50% by weight, preferably 1 to 30% by weight in the surface treatment agent.

In addition, suitable organic solvents include lower alcohols such as methanol, ethanol and isopropyl alcohol, or acetone, N, N-dimethylformamide, ethylene glycol, and the like, which can be freely mixed with water.

Copper compounds may be added to the surface treatment agents of the present invention to promote the rate of formation of a chemical layer on the surface of copper or copper alloy. In addition, zinc compounds may be added to further improve the thermal resistance of the formed chemical layer.

Representative examples of the copper compounds include copper acetate, copper chloride (I), copper chloride (II), copper bromide (I), copper bromide (II), copper iodide, copper hydroxide, copper phosphate, copper sulfate and copper nitrate ; Representative examples of the zinc compound include zinc oxide, zinc formate, zinc acetate, zinc oxalate, zinc lactate, zinc citrate, zinc sulfate, zinc nitrate and zinc phosphate. All of these may be contained in the ratio of 0.01 to 10% by weight, and preferably 0.02 to 5% by weight in the surface treatment agent.

When such a copper compound or a zinc compound is used, it is preferable to stabilize the pH of the solution by adding a substance having an amine compound that acts as a buffer such as ammonia, monoethanolamine, diethanolamine or triethanolamine to the organic or inorganic acid. can do.

For the purpose of further improving the rate of formation of the chemical layer and the heat resistance of the layer, the halogen compound (using "halogen" in a more general sense) is 0.001 to 1% by weight, and preferably 0.01 to 0.1% by weight. It may be added to the surface treatment agent in a ratio. Examples of such halogen compounds include sodium fluoride, potassium fluoride, ammonium fluoride, sodium chloride, potassium chloride, ammonium chloride, sodium bromide, potassium bromide, ammonium bromide, sodium iodide, potassium iodide and ammonium iodide.

For the surface treatment conditions of copper or copper alloy using the surface treating agent according to the present invention, the liquid temperature of the surface treating agent may preferably be 10 to 70 ° C., and the contact time may preferably be 1 second to 10 minutes. have. Examples of such contacting methods include dipping, spraying and coating methods.

In addition, after performing the surface treatment according to the present invention, it is possible to further improve heat resistance by forming a double layer structure comprising a chemical layer coated with a thermoplastic resin.

That is, after forming the chemical layer on the surface of copper or copper alloy, a rosin derivative (eg rosin or rosin ester), terpene resin derivative (eg terpene resin or terpene phenol resin), hydrocarbon A thermoplastic resin having good heat resistance, which may be composed of a resin (e.g., an aromatic hydrocarbon resin or an aliphatic hydrocarbon resin) or a mixture thereof, is dissolved in a solvent (e.g., toluene, ethyl acetate or isopropyl alcohol) and the solution By using a roll coater (roll coater) or the like on the chemical layer, for example, a uniform thickness of 1 to 30 ㎛ can be formed a double layer structure of the chemical layer and the thermoplastic resin.

Examples of lead-free solders suitable for the practice of the present invention include Sn-Ag-Cu based, Sn-Ag-Bi based, Sn-Bi based, Sn-Ag-Bi-In based, Sn-Zn based and Sn-Cu based solders. Lead-free solders such as;

The soldering method of the present invention is directed to a flow soldering or circuit pattern comprising moving a printed wiring board onto a molten liquid solder in a solder bath to solder the joint between the electronic components and the printed wiring board. Pre-printing paste cream solder on the printed wiring board; mounting electronic components thereon; and heating the entire printed wiring board to melt the solder to complete soldering. It can be applied to soldering.

Example

The following will specifically describe the present invention with reference to Examples and Comparative Examples, but the present invention should not be construed as being limited thereto.

In addition, the imidazole compounds and evaluation test methods used in the Examples and Comparative Examples are as follows.

(Imidazole compounds)

The imidazole compounds used in the examples are as follows and the synthesis examples are shown in Reference Examples 2 to 20. In addition, Reference Example 1 shows a synthesis example of (4-chlorophenyl) acetamidine hydrochloride, which is a raw material for the imidazole of Reference Example 2.

2- (4-chlorobenzyl) -4-phenylimidazole (referred to as "A-1")

2-benzyl-4- (4-chlorophenyl) -5-methylimidazole (referred to as "A-2")

2- (2-chlorobenzyl) -5-methyl-4-phenylimidazole (referred to as "A-3")

2- (2-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole (referred to as "B-1")

2- (4-chlorobenzyl) -4- (2-chlorophenyl) -5-methylimidazole (referred to as "B-2")

2- (4-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole (referred to as "B-3")

2- (2,4-dichlorobenzyl) -4-phenylimidazole (referred to as "C-1")

2-benzyl-4- (2,4-dichlorophenyl) -5-methylimidazole (referred to as "C-2")

5-hexyl-4-phenyl-2- (3,4,5-trichlorobenzyl) imidazole (5-hexyl-4-phenyl-2- (3,4,5- (trichlorobenzyl) imidazole) ("C -3 ")

4- (4-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole (referred to as "D-1")

4- (4-bromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole (4- (4-bromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole ) (Referred to as "D-2")

2- (2-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole (referred to as "D-3")

2- (4-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole (referred to as "D-4")

2- (4-bromobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole (referred to as "D-5")

2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (referred to as "D-6")

2- (4-chlorobenzyl) -5-methyl-4- (3,4,5-trichlorophenyl) imidazole (2- (4-chlorobenzyl) -5-methyl-4- (3,4,5 -trichlorophenyl) imidazole) (referred to as "D-7")

2- (2,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole (referred to as "E-1")

2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (referred to as "E-2")

2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (referred to as "E-3")

In this regard, as described above, the symbols A to E represent the following categories (A) to (E), respectively.

(A) imidazole compounds in which the hydrogen atom in only one of the benzyl group or the phenyl group is substituted with one halogen atom;

(B) imidazole compounds in which hydrogen atoms in both benzyl and phenyl groups are each substituted with one halogen atom;

(C) imidazole compounds in which hydrogen atoms in only one of the benzyl group or the phenyl group are substituted with two or more halogen atoms;

(D) imidazole compounds in which hydrogen atoms in either the benzyl group or the phenyl group are substituted with two or more halogen atoms and hydrogen atoms in the other place are substituted with one halogen atom, and

(E) Imidazole compounds in which hydrogen atoms in both benzyl and phenyl groups are each substituted with two or more halogen atoms.

Reference Example 1

Synthesis of (4-chlorophenyl) acetamidine hydrochloride

A solution containing 137.2 g (0.905 mol) of (4-chlorophenyl) acetonitrile and 51.1 g (1.11 mol) of dry ethanol was prepared, and 36.7 g (1.01 mol) of hydrogen chloride were 15-20. It was added over 2 hours while cooling at 캜. While the hydrogen chloride gas was added, a solid formed. When the reaction mixture was left at room temperature overnight, ethyl (4-chlorophenyl) acetimide hydrochloride was obtained as a white solid. After pulverizing the solid, a solution consisting of 28.4 g (1.67 mol) of ammonia and 250 g of dry ethanol was added thereto portionwise with stirring under ice cooling. After the addition was completed, the mixture was stirred for 1 hour with ice cooling and then overnight at room temperature. After filtering off the insoluble matters of the white solid, the filtrate was concentrated to dryness in vacuo to give 178 g (0.868 moles, yield 96%) of (4-chlorophenyl) acetamide hydrochloride as white crystals.

Reference Example 2

Synthesis of A-1

To a solution containing 61.5 g (0.30 mol) of (4-chlorophenyl) acetamidine hydrochloride and 250 ml of tetrahydrofuran was added 16.2 g (0.30 mol) of sodium methylate and then heated at 50 ° C. for one hour. . 83 g (0.60 mol) of potassium carbonate were then added thereto. A solution consisting of 59.7 g (0.30 mol) of 2-bromoacetophenone and 200 ml of tetrahydrofuran was added dropwise to the resulting suspension at 50-55 ° C. After completion of the dropwise addition, the mixture was heated at reflux for 2 hours. Next, the reaction mixture was cooled to room temperature, insoluble materials were filtered off and the filtrate was concentrated to dryness in vacuo. After washing with water, the concentrate was stirred with toluene to precipitate crystals. The crystals collected by filtration were decolorized with activated carbon in methanol and then recrystallized to give 25 g (0.093 mol, 31 g) of slightly pink crystals.

Reference Example 3

Synthesis of A-2

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with phenylacetonitrile, and phenylacetamidine hydrochloride was synthesized according to the method of Reference Example 1.

Next, 2-bromoacetophenone (2-bromo-4'-chloropropiophenone (2-bromo-) as (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 was substituted with phenylacetamidine hydrochloride. 4'-chloropropiophenone), and 2-benzyl-4- (4-chlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 4

Synthesis of A-3

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2-chlorophenyl) acetonitrile ((2-chlorophenyl) acetonitrile), and according to the method of Reference Example 1, (2-chlorophenyl) acetami Dean hydrochloride ((2-chlorophenyl) acetamidine hydrochloride) was synthesized.

Next, 2-bromoacetophenone was substituted with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2-bromopropiophenone) with (2-chlorophenyl) acetamide hydrochloride. And 2- (2-chlorobenzyl) -5-methyl-4-phenylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 5

Synthesis of B-1

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2-chlorophenyl) acetonitrile, and (2-chlorophenyl) acetamidine hydrochloride was synthesized according to the method of Reference Example 1.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2-chlorophenyl) acetamide hydrochloride, and 2-bromo-4'-chloropropiophenone was added. And 2- (2-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 6

Synthesis of B-2

2-bromoacetophenone of Reference Example 2 was replaced with 2-bromo-2'-chloropropionphenone, and 2- (4-chloro according to the method of Reference Example 2 Benzyl) -4- (2-chlorophenyl) -5-methylimidazole was synthesized.

Reference Example 7

Synthesis of B-3

Replace 2-bromoacetophenone of Reference Example 2 with 2-bromo-4'-chloropropiophenone and follow the method of Reference Example 2 to 2- (4-chlorobenzyl) -4- (4-chlorophenyl ) -5-methylimidazole was synthesized.

Reference Example 8

Synthesis of C-1

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2,4-dichlorophenyl) acetonitrile ((2,4-dichlorophenyl) acetonitrile), followed by the method of Reference Example 1 (2,4 -(Dichlorophenyl) acetamidine hydrochloride ((2,4-dichlorophenyl) acetoamidine hydrochloride) was synthesized.

Next, (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 was replaced with (2,4-dichlorophenyl) acetamidine hydrochloride and 2- (2,4- according to the method of Reference Example 2 Dichlorobenzyl) -4-phenylimidazole was synthesized.

Reference Example 9

Synthesis of C-2

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with phenylacetonitrile, and phenylacetamidine hydrochloride was synthesized according to the method of Reference Example 1.

Next, 2-bromoacetophenone (2-bromo-2 ', 4'-dichloropropiophenone (2) as (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 was used as phenylacetamidine hydrochloride. -bromo-2 ', 4'-dichloropropiophenone), and 2-benzyl-4- (2,4-dichlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 10

Synthesis of C-3

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (3,4,5-trichlorophenyl) acetonitrile ((3,4,5-trichlorophenyl) acetonitrile), and the method of Reference Example 1 (3,4,5-trichlorophenyl) acetamidine hydrochloride was synthesized accordingly.

Next, 2-bromoacetophenone was substituted with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (3,4,5-trichlorophenyl) acetamidine hydrochloride and 2-bromooctanophenone was added. (2-bromooctanophenone) and 5-hexyl-4-phenyl-2- (3,4,5-trichlorobenzyl) imidazole were synthesized according to the method of Reference Example 2.

Reference Example 11

Synthesis of D-1

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2,4-dichlorophenyl) acetonitrile, and (2,4-dichlorophenyl) acetamidine hydrochloride was prepared according to the method of Reference Example 1. Synthesized.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2,4-dichlorophenyl) acetamidine hydrochloride. Substituted with fenone and 4- (4-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 12

Synthesis of D-2

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2,4-dichlorophenyl) acetonitrile, and (2,4-dichlorophenyl) acetamidine hydrochloride was prepared according to the method of Reference Example 1. Synthesized.

Next, 2-bromoacetophenone was substituted with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 and (2,4-dichlorophenyl) acetamidine hydrochloride to 2,4'-dibromopropiope. Substituted with 2-bromopropiophenone, 4- (4-bromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 13

Synthesis of D-3

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2-chlorophenyl) acetonitrile, and (2-chlorophenyl) acetamidine hydrochloride was synthesized according to the method of Reference Example 1.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2-chlorophenyl) acetamide hydrochloride, and 2-bromo-2 ', 4'-dichloro Substituted with acetophenone (2-bromo-2 ', 4'-dichloroacetophenone), and 2- (2-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole was synthesized according to the method of Reference Example 2. .

Reference Example 14

Synthesis of D-4

Replace 2-bromoacetophenone of Reference Example 2 with 2-bromo-2 ', 4'-dichloroacetophenone, and follow the method of Reference Example 2 to 2- (4-chlorobenzyl) -4- (2, 4-dichlorophenyl) imidazole was synthesized.

Reference Example 15

Synthesis of D-5

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (4-bromophenyl) acetonitrile ((4-bromophenyl) acetonitrile), followed by the method of Reference Example 1 (4-bromophenyl) Acetamidine hydrochloride ((4-bromophenyl) acetamidine hydrochloride) was synthesized.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 with (4-bromophenyl) acetamidine hydrochloride; 2-bromo-2 ', 4'- Substituted with dichloropropiophenone, 2- (4-bromobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 16

Synthesis of D-6

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (4-bromophenyl) acetonitrile ((4-bromophenyl) acetonitrile), followed by the method of Reference Example 1 (4-bromophenyl) Acetamidine hydrochloride was synthesized.

Next, 2-bromoacetophenone was replaced with (4-brophenyl) acetamidine hydrochloride of Reference Example 2 with (4-bromophenyl) acetamide hydrochloride; 2-bromo-3 ', 4'- Dichloropropiophenone (2-bromo-3 ', 4'-dichloropropiophenone) and 2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5 according to the method of Reference Example 2 -Methylimidazole was synthesized.

Reference Example 17

Synthesis of D-7

2-bromoacetophenone of Reference Example 2 was replaced with 2-bromo-3 ', 4', 5'-trichloropropiophenone (2-bromo-3 ', 4', 5'-trichloropropiophenone), 2- (4-chlorobenzyl) -5-methyl-4- (3,4,5-trichlorophenyl) imidazole was synthesized according to the method of Reference Example 2.

Reference Example 18

Synthesis of E-1

First, replace (4-chlorophenyl) acetonitrile of Reference Example 1 with (2,4-dichlorophenyl) acetonitrile, and follow the method of Reference Example 1 to (2,4-dibromophenyl) acetamidine hydro Chloride ((2,4-dibromophenyl) acetamidine hydrochloride) was synthesized.

Next, 2-bromoacetophenone was substituted with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2,4-dichlorophenyl) acetamidine hydrochloride and 2-bromo-2 ', 4'. -Dichloropropiophenone was replaced and 2- (2,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 19

Synthesis of E-2

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2,4-dichlorophenyl) acetonitrile, and (2,4-dichlorophenyl) acetamidine hydrochloride was prepared according to the method of Reference Example 1. Synthesized.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2,4-dichlorophenyl) acetamidine hydrochloride, and 2-bromo-3 ', 4'. -Dichloropropiophenone was replaced, and 2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 20

Synthesis of E-3

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (3,4-dichlorophenyl) acetonitrile ((3,4-dichlorophenyl) acetonitrile), followed by the method of Reference Example 1 (3,4 -(Dichlorophenyl) acetamidine hydrochloride ((3,4-dichlorophenyl) acetamidine hydrochloride) was synthesized.

Next, 2-bromoacetophenone was replaced with (4-, chlorophenyl) acetamidine hydrochloride of Reference Example 2 (3,4-dichlorophenyl) acetamidine hydrochloride, and 2-bromo-3 ', 4'. -Dichloropropiophenone was replaced, and 2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole was synthesized according to the method of Reference Example 2.

The imidazole compounds used in the comparative examples are as follows.

2-benzyl-4-phenylimidazole (referred to as "Z-1")

2-benzyl-5-chloro-4-methylimidazole (referred to as "Z-2")

2- (4-chlorobenzyl) imidazole (referred to as "Z-3")

2- (2,4-dichlorobenzyl) -4,5-diphenylimidazole (2- (2,4-dichlorobenzyl) -4,5-diphenylimidazole) (referred to as "Z-4")

4-methyl-2-phenylimidazole (referred to as "Z-5")

2- (4-chlorobenzyl) benzimidazole (referred to as "Z-6")

Synthesis examples of Z-1, Z-2, Z-3 and Z-4 are shown in Reference Examples 21-24. For Z-5 and Z-6, the trade name "Curesol 2P4MZ" manufactured by Shikoku Chemical Co., Ltd. and the reagent manufactured by Wako Pure Chemical Industries, Ltd. were used, respectively.

Reference Example 21

Synthesis of Z-1

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with phenylacetonitrile, and phenylacetamidine hydrochloride was synthesized according to the method of Reference Example 1.

Next, (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 was replaced with phenylacetamidine hydrochloride, and 2-benzyl-4-phenylimidazole was synthesized according to the method of Reference Example 2.

Reference Example 22

Synthesis of Z-2

2-benzyl-4-methylimidazole (2-benzyl-4-methylimidazole) (manufactured by POLY ORGANIX, "2B4MI") 16 g (0.093 mol) and N-chlorosuccinimide ( 13.3 g (0.1 mol) of N-chlorosuccinimide) was added in portions at room temperature. After stirring the mixture for 1 hour, the reaction mixture was concentrated to dryness in vacuo and the dry material was washed with hot water. Thereafter, recrystallization from acetonitrile gave 8.5 g (0.041 mol, yield: 44%) of 2-benzyl-5-chloro-4-methylimidazole as slightly beige needle crystals.

Reference Example 23

Synthesis of Z-3

A solution of 52.0 g (0.343 mol) of (4-chlorophenyl) acetonitrile, 22.8 g (0.38 mol) of ethylenediamine and 0.21 g (6.5 mol) of sulfur was heated with stirring to bring the temperature from 150 ° C. to 280 ° C. Raised over 2 hours. After cooling the mixture, a solution consisting of 1.0 g sodium hydroxide and 10 ml methanol was added thereto and then heated at reflux for 3 hours. After concentrating the reaction mixture in vacuo, the concentrate was distilled in vacuo to yield 2- (4-chlorobenzyl) imidazoline (2- (4-chlorobenzyl) as a fraction with a boiling point of 163 to 170 ° C / 4 mmHg. imidazoline) 43 g (0.22 mole, yield: 64%) were obtained.

Next, 27 g (0.17 mol) of potassium permanganate were added in portions to a solution consisting of 21 g (0.108 mol) of the 2- (4-chlorobenzyl) imidazoline and 250 ml of dioxane at room temperature. After heating the mixture at reflux for 8 hours, the insoluble materials were filtered off and the filtrate was concentrated to dryness in vacuo. After washing the dry product with water, the product was recrystallized from water-acetonitrile to give 13.5 g (0.070 mol, yield: 65%) of 2- (4-chlorobenzyl) imidazole as milky crystals.

Reference Example 24

Synthesis of Z-4

First, (4-chlorophenyl) acetonitrile of Reference Example 1 was replaced with (2,4-dichlorophenyl) acetonitrile, and (2,4-dichlorophenyl) acetamidine hydrochloride was prepared according to the method of Reference Example 1. Synthesized.

Next, 2-bromoacetophenone was replaced with (4-chlorophenyl) acetamidine hydrochloride of Reference Example 2 (2,4-dichlorophenyl) acetamide hydrochloride and 2-bromo-2-phenylacetophenone (2-bromo-2-phenylacetophenone) and 2- (2,4-dichlorobenzyl) -4,5-diphenylimidazole were synthesized according to the method of Reference Example 2.

The formulas of the imidazole compounds used in the examples are shown below:

The chemical formulas of the imidazole compounds used in the comparative examples are shown below.

Evaluation test methods employed in the Examples and Comparative Examples are as follows.

(Evaluation test for solder flow-up speed characteristics)

A printed wiring board made of 120 mm (length) x 150 mm (width) x 1.6 mm (thick) glass epoxy resin and having 300 copper through holes having an inner diameter of 0.80 mm was used as a test piece. The test piece was degreased and washed with water after soft etching. The test piece was then immersed in a surface treating agent maintained at a predetermined liquid temperature for a predetermined time, washed with water and then dried to form a chemical layer having a thickness of about 0.10 to 0.50 μm on the copper surface.

The surface-treated specimen was subjected to an infrared reflow oven (trade name: MULTI-PRO-306, manufactured by Vetronix, Inc.) with a peak temperature of 240 ° C., followed by a flow soldering device (conveyor speed: 1.0 m / min). The reflow-heating in which the soldering was performed was subjected to three cycles.

The solder used here is a tin-lead process solder (trade name: H63A, manufactured by Senju Metal Industry Co., Ltd.) having a composition of 63% tin and 37% lead by weight, and the flux used for soldering is JS-64MSS. (Manufactured by Koki Corporation). Soldering temperature was 240 degreeC.

The specimen surface treated as above was also soldered using lead-free solder in the same manner as for the tin-lead process solder. The solder used here is a lead-free solder (trade name: H705 "ECOSOLDER" manufactured by Senju Metal Industry Co., Ltd.) having a composition of 96.5% tin, 3.0% silver and 0.5% copper (% by weight), and the flux used for soldering is JS- It was E-09 (made by Koki Corporation). The reflow-heat peak temperature was 245 ° C and the soldering temperature was 245 ° C.

For the soldered test piece, the numerical ratio (%) of the solder-filled (soldered) copper through hole to the upper land of the copper through hole relative to the total number of copper through holes (300 holes) was calculated.

When the solder wettability on the copper surface is large, molten solder penetrates into each copper through hole, thereby easily filling the molten solder into the upper land of the through hole. That is, when the number ratio of the through holes soldered to the upper lands relative to the total number of through holes is large, it will be determined that solder wettability and solderability to copper are excellent.

(Evaluation test for solder spreadability)

A printed wiring board made of a 50 mm (length) x 50 mm (width) x 1.2 mm (thick) glass epoxy resin was used as a test piece. This printed wiring board had a circuit pattern in which 10 pieces of copper-foil circuit having a conductor width of 0.80 mm and a length of 20 mm were formed in the longitudinal direction at intervals of 1.0 mm. The test piece was degreased and washed with water after soft etching. The test piece was then immersed in a surface treating agent maintained at a predetermined liquid temperature for a predetermined time, washed with water and then dried to form a chemical layer having a thickness of about 0.10 to 0.50 μm on the copper surface.

The surface-treated test pieces were subjected to one cycle of reflow-heating with a peak temperature of 240 ° C using an infrared reflow oven (trade name: MULTI-PRO-306, manufactured by Vetronix Corporation). Thereafter, tin-lead solder paste was printed at the center of the copper circuit portions using a metal mask having an opening diameter of 1.2 mm and a thickness of 150 mm, reflow-heating was performed and soldering was performed under the above-described conditions. The solder used here was a process solder (trade name: OZ-63-330F-40-10, manufactured by Senju Metal Industry Co., Ltd.) consisting of 63% tin and 37% lead (% by weight).

The specimen surface treated as above was also soldered using lead-free solder in the same manner as for the tin-lead process solder. The lead-free solder used here consisted of 96.5% tin, 3.0% silver and 0.5% copper (wt%) (trade name: M705-221BM5-42-11, manufactured by Senju Metal Industry Co., Ltd.). The peak temperature of the reflow-heating obtained before and after the solder paste printing was set to 245 ° C.

The length (mm) of the solder wet and spread on the copper circuit portion of the obtained test piece was measured.

If the length is long, it will be judged that solder wettability and solderability are excellent.

Example 1

After dissolving copper acetate and zinc chloride in deionized water with 2- (4-chlorobenzyl) -4-phenylimidazole as imidazole compound, levulinic acid as acid and metal salts in deionized water to obtain the composition described in Table 1, The surface treatment agent was prepared by adjusting the pH to 3.6 with ammonia water.

Next, the test piece of the printed wiring board was immersed in the surface treatment agent adjusted at a temperature of 40 ℃ for 30 seconds, washed with water and then dried to measure the solder flow-up rate characteristics and solder spreadability. These test results are shown in Table 1.

Examples 2 to 19

Using the imidazole compound, acid, metal salt and halogen compound as described in Table 1 or 2, surface treating agents having the compositions described in Table 1 or 2, respectively, were prepared in the same manner as in Example 1 and The surface was treated under the described treatment conditions. For the resulting test pieces, solder flow-up rate characteristics and solder spreadability were measured. These test results are shown in Table 1 or 2.

Example One 2 3 4 5 6 7 8 9 Composition of surface treatment agent (% by weight-balance is water) Imidazole:







2- (4-chlorobenzyl) -4-phenylimidazole (A-1) 0.25 2-benzyl-4- (4-chlorophenyl) -5-methylimidazole (A-2) 0.25 2- (2-chlorobenzyl) -5-methyl-4-phenylimidazole (A-3) 0.25 2- (2-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole (B-1) 0.25 2- (4-chlorobenzyl) -4- (2-chlorophenyl) -5-methylimidazole (B-2) 0.25 2- (4-chlorobenzyl) -4- (4-chlorophenyl) -5-methylimidazole (B-3) 0.25 2- (2,4-dichlorobenzyl) -4-phenylimidazole (C-1) 0.25 2-benzyl-4- (2,4-dichlorophenyl) -5-methylimidazole (C-2) 0.25 5-hexyl-4-phenyl-2- (3,4,5-trichlorobenzyl) imidazole (C-3) 0.20 mountain:


Formic acid 10 Acetic acid 10 10 20 20 20 10 20 Lactic acid Levulinic acid 10 20 5 Metal salt:



Copper acetate 0.10 0.10 Copper chloride (II) 0.08 Copper bromide (II) 0.10 0.10 0.10 0.10 Zinc acetate 1.00 Zinc chloride 0.20 0.20 halogen:





Ammonium chloride 0.05 0.03 Potassium chloride 0.20 Ammonium bromide 0.05 Potassium bromide Ammonium Iodide 0.07 0.07 0.07 0.02 Potassium Iodide 0.02 Copper iodide   PH 3.6 3.1 3.5 3.3 3.2 3.4 2.9 3.2 2.4 Processing conditions
Treatment temperature (℃) 40 40 40 40 40 40 40 30 50 Processing time (seconds) 30 180 60 300 180 120 300 300 300 Evaluation test


Solder Flow-up Rate Characteristics (%) Process solder 100 100 98 100 100 100 100 100 100 Lead free solder 84 85 84 90 90 92 95 97 100 Solder Spreadability (mm)
Process solder 3.24 3.31 3.17 3.48 3.47 3.51 3.78 3.81 3.92 Lead free solder 1.61 1.60 1.60 1.64 1.64 1.65 1.68 1.70 1.69

Example 10 11 12 13 14 15 16 17 18 19 Composition of surface treatment agent (% by weight-balance is water) Imidazole:
4- (4-chlorophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole (D-1) 0.25 4- (4-Bromophenyl) -2- (2,4-dichlorobenzyl) -5-methylimidazole (D-2) 0.20 2- (2-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole (D-3) 0.25 2- (4-chlorobenzyl) -4- (2,4-dichlorophenyl) imidazole (D-4) 0.25 2- (4-bromobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole (D-5) 0.25 2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (D-6) 0.25 2- (4-chlorobenzyl) -5-methyl-4- (3,4,5-trichlorophenyl) -5-methylimidazole (D-7)
0.20 2- (2,4-dichlorobenzyl) -4- (2,4-dichlorophenyl) -5-methylimidazole (E-1) 0.20 2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (E-2) 0.20 2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (E-3) 0.20 mountain:


Formic acid 20 Acetic acid 15 25 20 30 10 20 25 30 Lactic acid 15 20 Levulinic acid 10 Metal salt:



Copper acetate 0.06 0.06 0.05 0.05 0.05 0.20 0.20 0.20 Copper chloride (II) Copper bromide (II) Zinc acetate 1.00 1.00 3.00 3.00 3.00 Zinc chloride 0.20 halogen:





Ammonium chloride 0.45 Potassium chloride 0.04 0.20 Ammonium bromide 0.40 Potassium bromide 0.10 0.10 0.10 Ammonium Iodide 0.03 0.03 Potassium Iodide 0.08 0.04 0.04 Copper iodide 0.05   PH 2.8 2.7 3.1 2.7 3.1 3.2 2.3 3.5 3.2 2.8 Processing conditions
Treatment temperature (℃) 50 50 40 40 40 40 50 40 40 50 Processing time (seconds) 120 300 120 180 90 90 600 90 90 300 Evaluation test:


Solder Flow-up Rate
characteristic(%) Process solder 100 100 100 100 100 100 100 100 100 100 Lead free solder 98 97 96 100 100 97 100 100 100 100 Solder Spreadability (mm)
Process solder 3.84 3.77 3.77 3.87 3.82 3.77 3.89 3.94 3.98 3.92 Lead free solder 1.67 1.67 1.68 1.69 1.71 1.70 1.71 1.71 1.71 1.70

Comparative Examples 1 to 6

Using the imidazole compounds, acids, metal salts and halogen compounds as described in Table 3, surface treating agents each having the composition described in Table 3 were prepared in the same manner as in Example 1 and surfaced under the treatment conditions described in Table 3 Processed. For the resulting test pieces, solder flow-up rate characteristics and solder spreadability were measured. These test results are shown in Table 3.

Example One 2 3 4 5 6 Composition of surface treatment agent (% by weight-balance is water) Imidazole:





2-benzyl-4-phenylimidazole (Z-1) 0.30 2-benzyl-5-chloro-4-methylimidazole (Z-2) 0.20 2- (4-chlorobenzyl) imidazole (Z-3) 0.30 2- (2,4-dichlorobenzyl) -4,6-diphenylimidazole (Z-4) 0.20 4-methyl-2-phenylimidazole (Z-5) 0.30 2- (4-chlorobenzyl) benzimidazole (Z-6) 0.25 mountain:


Formic acid 5 Acetic acid 10 10 10 20 10 Lactic acid Levulinic acid 10 10 Metal salt:



Copper acetate 0.20 0.20 0.10 Copper chloride (II) 0.15 Copper bromide (II) 0.09 0.07 0.05 Zinc acetate Zinc chloride 0.20 halogen:





Ammonium chloride 0.10 Potassium chloride Ammonium bromide 0.07 Potassium bromide Ammonium Iodide Potassium Iodide Copper iodide   PH 4.0 3.4 3.9 3.2 4.2 3.6 Processing conditions
Treatment temperature (℃) 40 40 40 40 50 40 Processing time (seconds) 120 300 180 60 300 90 Evaluation test


Solder Flow-up Rate Characteristics (%) Process solder 52 47 28 76 35 84 Lead free solder 27 22 17 62 23 42 Solder Spreadability (mm)
Process solder 2.34 2.18 2.11 2.40 2.16 2.48 Lead free solder 1.41 1.38 1.35 1.47 1.37 1.48

According to the test results shown in Table 1 (Examples 1 to 9) and Table 2 (Examples 10 to 19), the solder wettability of the process solder or lead-free solder to the copper surface of the printed wiring board is the surface according to the present invention. It is evident that the treatment agent is enhanced by contacting the copper surface to form a chemical layer and that the solderability (solder flow-up rate characteristics, solder spreadability) of the process solder or lead-free solder to the copper surface is excellent.

In Examples 1-19, it was found that the solder flow-up rate properties were 100% in almost all cases when using process solder (98% only in Example 3) and no differences were observed between Examples 1-19. Do not. However, for the solder flow-up rate characteristics when using lead-free solder and the solder spreadability when using a process solder or a lead-free solder, Examples 1 to 3 (hereinafter referred to as Case A) are implemented. Some differences are observed between Examples 4-6 (hereinafter referred to as Case B) and Examples 7-19 (hereinafter referred to as Case C). That is, the solder flow-up rate characteristics when using lead-free solder and the solder spreadability when using process solder or lead-free solder are improved in the order of Case A <Case B <Case C.

As mentioned above, the imidazole compounds used in case A are imidazole compounds in which the hydrogen atom in either the benzyl group or the phenyl group is substituted with one halogen atom. The imidazole compounds used in case B are imidazole compounds in which hydrogen atoms in both benzyl and phenyl groups are each substituted with one halogen atom. The imidazole compounds used in case C are (i) imidazole compounds in which hydrogen atoms in only one of the benzyl or phenyl groups are substituted with two or more halogen atoms (Examples 7 to 9), (ii) the benzyl group or Imidazole compounds in which hydrogen atoms in any one of the phenyl groups are substituted with two or more halogen atoms and hydrogen atoms in other places substituted with one halogen atom (Examples 10 to 16), and (iii) both benzyl and phenyl groups Are imidazole compounds (Examples 17-19) in which the hydrogen atoms in each are substituted with two halogen atoms.

According to the test results shown in Table 3 (Comparative Examples 1 to 6), the solderability is relatively good when the surface treatment agent of Comparative Example 4 is used. The imidazole compound (Z-4) used in the surface treating agent is an imidazole compound in which two hydrogen atoms in the benzyl group are substituted with two halogen atoms, but the imidazole compound is bonded at the 5-position of the imidazole ring. The different kinds of substituents are different from the imidazole compounds of formula (I) which are suitable for the practice of the present invention. That is, in the test results of Comparative Example 4, the benzyl group in which two hydrogen atoms in the benzyl group are substituted with two halogen atoms is bonded to the 2-position of the imidazole ring, and the phenyl group is bonded to the 4-position. It can be said that there is an improvement effect on the solderability derived from the chemical structure. However, imidazole compounds suitable for the practice of the present invention, unlike Z-4, have the above chemical structure in which a hydrogen atom or an alkyl group is bonded at the 5-position of the imidazole ring instead of a phenyl group. This is a feature of imidazole compounds suitable for the practice of the present invention, leading to the improved results demonstrated above.

Although the surface treatment agent according to the present invention can be easily used in soldering using a process solder, it can also be suitably used for soldering using a lead-free solder showing poor solderability compared to the process solder.

When the electronic component and the like are mounted on a printed wiring board using solder, the present invention forms a chemical layer having excellent heat resistance on the surface of copper or a copper alloy constituting a circuit portion such as a printed wiring board and simultaneously The present invention relates to a surface treatment agent and a surface treatment method for improving wettability and improving solderability.

In addition, the present invention can provide a printed wiring board produced by contacting the surface of the copper or copper alloy constituting the copper circuit portion with the surface treatment agent, and after contacting the surface of the copper or copper alloy with the surface treatment agent It is possible to provide a soldering method for performing soldering using lead-free solder.

While the invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope thereof.

This application contains Japanese Patent Application No. 2008-206119, filed on August 8, 2008, Japanese Patent Application No. 2008-295619, filed on November 19, 2008, and Japanese Patent Application No., filed on May 22, 2009. Based on 2009-124003, the entire contents of which are incorporated herein by reference.

Claims (6)

In the surface treating agent for copper or copper alloy containing the imidazole compound represented by Formula (I):

R represents a hydrogen atom or an alkyl group,
X ₁ and X ₂ are the same or different and represent a chlorine atom or a bromine atom,
m and n represent the integer of 0-3, and at least 1 of m or n is 1 or more, The surface treating agent characterized by the above-mentioned. The method of claim 1,
m and n are each 1 or more, The surface treating agent characterized by the above-mentioned. The method of claim 1,
At least one of m or n is 2 or more, the surface treatment agent. In the surface treatment method of copper or a copper alloy,
A method of surface treatment comprising the step of contacting a surface of said copper or said alloy with a surface treating agent according to any one of claims 1 to 3. A printed wiring board comprising copper or a copper alloy constituting a copper circuit portion,
The surface of the copper or alloy is in contact with the surface treatment agent according to any one of claims 1 to 3. Contacting the surface of the copper or copper alloy with the surface treating agent according to any one of claims 1 to 3; And
Thereafter, performing soldering with the lead-free solder.