JPH0465495A - Cleaner of rosin-based solder flux and cleaning of rosin-based solder flux using the same cleaning agent - Google Patents

Abstract

PURPOSE:To obtain the title cleaner having excellent cleaning power, sufficiently satisfiable in terms of environmental destruction, ignitability, smell, etc., containing a mixture of a specific glycol ether and a specific hydrocarbon compound as an active ingredient. CONSTITUTION:The objective cleaner containing a mixture of (A) usually about 10-90 wt.% (preferably about 40-60 wt.%) one or more glycol ether-based compounds shown by the formula (R<1> is H or 1-5C alkyl; R<2> is 1-5C alkyl; R<3> is H or methyl; m is 2-4 integer and (B) usually about 90-10 wt.% (preferably about 60-40 wt.%) 8-14C hydrocarbon compound as an active ingredient.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a cleaning agent for rosin-based solder flux, particularly a cleaning agent for rosin-based solder flux for assembly, and a cleaning agent for rosin-based solder flux using the cleaning agent. Regarding the method.

(Prior Art) Rosin-based solder flux is used in the production of modules such as printed circuit boards and printed wiring boards. The purpose of soldering is generally to increase the adhesive strength between the board and the input/output pins, and to prevent oxidation of the contacts and maintain conductivity. Solder flux is used. After soldering is completed, a cleaning agent is used to selectively and completely remove only the flux from the board surface. In other words, if the flux is not sufficiently cleaned, the residual flux may cause circuit corrosion, or the electrical insulation of the board surface may deteriorate.
This has the disadvantage of ultimately leading to circuit damage. Therefore, the disadvantages mentioned above are overcome by using cleaning agents to remove the residual flux, especially the activator components contained therein.

Conventionally, halogenated hydrocarbon solvents such as so-called chlorofluorocarbons such as trichlorethylene and trichlorotrifluoroethane have been used as cleaning agents for rosin-based solder flux. However, due to environmental pollution issues such as ozone layer depletion, restrictions on the use of halogenated hydrocarbon cleaning agents are becoming more serious, and there is an urgent need in the electronics industry to develop cleaning agents for solder flux that can replace so-called fluorocarbons. It's here.

Recently, various non-halogen solder flux cleaning agents have been developed, but the current situation is that no one has yet been found that completely satisfies all required performance such as cleaning power, odor, and flammability. .

(Problems to be Solved by the Invention) The present invention provides a non-halogen solder flux cleaning agent that has excellent cleaning power and is substantially satisfactory in terms of environmental characteristics, odor, flammability, etc., and uses the cleaning agent. The purpose is to provide a cleaning method.

(Means for Solving the Problems) As a result of intensive studies to achieve the above object, the present inventors unexpectedly found that a mixture consisting of a specific glycol ether compound and a hydrocarbon compound having 8 to 14 carbon atoms. The present inventors have discovered that all of the above problems can be solved when a mixture containing a nonionic surfactant and a nonionic surfactant is used as an essential component, and the present invention has been completed.

That is, the present invention provides (Il-Shipura (1): % formula % (wherein, R'' is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R2 is an alkyl group having 1 to 5 carbon atoms, and R3 is Contains as an active ingredient a mixture consisting of at least one glycol ether compound represented by a hydrogen atom or a methyl group (m is an integer of 2 to 4), and a hydrocarbon compound having 8 to 14 carbon atoms. A rosin-based solder flux cleaning agent (hereinafter referred to as cleaning agent@) that is characterized by:
, and (II)-Ship (1).

R' O-(CH2CHO), -R'' (in the formula, R1
is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R2 is an alkyl group having 1 to 5 carbon atoms, R3 is a hydrogen atom or a methyl group, and m is an integer of 2 to 4). At least one type of compound having 8 or more carbon atoms
A rosin-based solder flux cleaning agent (hereinafter referred to as cleaning agent
The present invention further relates to (m) a method for cleaning rosin-based solder flux, which comprises bringing the cleaning agent into contact with rosin-based solder flux.

Among the components of the rosin-based solder flux cleaning agent of the present invention, the glycol ether compounds represented by the above-mentioned (1) include diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, and diethylene glycol Methyl ethyl ether, diethylene glycol monopropyl ether, diethylene glycol dipropyl ether, diethylene glycol methylpropyl ether, diethylene glycol ethyl propyl ether, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl butyl ether,
Diethylene glycol ethyl butyl ether, diethylene glycol propyl butyl ether, diethylene glycol monopentyl ether, diethylene glycol diethyl ether, diethylene glycol methyl pentyl ether, diethylene glycol ethyl bentyl ether, diethylene glycol propyl pentyl ether, diethylene glycol butyl pentyl ether: corresponding tri- or tetraethylene glycol ethers Examples include di-, tri- or tetrapropylene glycol ethers corresponding to these. These compounds can be used alone or in an appropriate combination of two or more.

Among the components of the cleaning agent for the rosin-based solder flux of the present invention, examples of hydrocarbon compounds having 8 to 14 carbon atoms include linear or branched alkanes having 8 to 14 carbon atoms;
4 straight-chain or branched alkenes are suitable. In consideration of detergency and flammability, hydrocarbon compounds having 11 to 13 carbon atoms are preferred.

Specific examples of hydrocarbon compounds having 8 to 14 carbon atoms include octane, nonane, decane, undecane, dodecane, tridecane, and tetradecane; branched alkanes corresponding to these; linear or branched alkanes corresponding to these; Alkenes:
The corresponding cycloalkanes and cycloalkenes are listed below.

The rosin-based solder flux cleaning agent of the present invention ■ is a cleaning agent ■
In addition to this, it contains a nonionic surfactant. When using nonionic surfactants.

That is, when cleaning agent (2) is used, the final cleanliness of the substrate after passing through the continuous water washing process is better than when cleaning rosin flux with cleaning agent (2). The nonionic surfactant is not particularly limited as long as its ionicity is nonionic, and various known surfactants may be used.

A specific example is polyoxyethylene alkyl (C
, <) Polyethylene glycol ether type nonionic surfactants such as ether, polyoxyethylene phenol ether, and polyoxyethylene alkyl phenol ether; Polyethylene glycol ester type nonionic surfactants such as polyethylene glycol monoester and polyethylene glycol diester: Higher fats Ethylene oxide adducts of fatty acid amides; polyhydric alcohol-type nonionic surfactants such as sorbitan fatty acid esters and sucrose fatty acid esters; fatty acid alkanolamides, etc., and polyoxypropylene corresponding to these. Examples include nonionic surfactants based on polyoxyethylene and polyoxypropylene copolymer. These nonionic surfactants can be used alone or in combination of two or more.

Among these, polyethylene glycol ether nonionic surfactants are preferred in terms of detergency, and even more preferred are the following - Shipura (2)
) is applicable.

R'O-(CH2CH,O). -H (in the formula,
R4 is a linear or branched alkyl group having 6 to 20 carbon atoms, preferably 10 to 14 carbon atoms, a phenyl group, or a carbon number 7
a phenyl group substituted with ~12 straight or branched alkyl groups, n is an integer of 2 to 20, preferably 3 to 1
Indicates an integer of 6. ) In the cleaning agent (1), the ratio of the glycol ether compound and the hydrocarbon compound to be used is not particularly limited, but is usually about 10 to 90% by weight and about 90 to 10% by weight, preferably about 90 to 10% by weight. are approximately 40 to 60% by weight: approximately 60 to 40% by weight.

Regarding the cleaning agent, the proportions of the glycol ether compound, the hydrocarbon compound, and the nonionic surfactant are not particularly limited, but are usually about 10 to 80% by weight in that order: 90 to 80% by weight. It is about 20% by weight and less than about 30% by weight, preferably about 40 to 60% by weight, about 60 to 40% by weight = about 10 to 20% by weight.

The cleaning agents (1) and (2) of the present invention are both applicable to cleaning rosin-based solder flux, particularly rosin-based solder flux for assembly. The flux includes an inactive rosin flux mainly composed of rosins such as rosin and modified rosin, and rosins and activators (for example, triethanolamine hydrochloride, triethylenetetramine hydrochloride, cyclohexylamine hydrochloride, etc.). Activated rosin fluxes whose main components are organic or inorganic acid salts of amine compounds such as aniline hydrochloride are common. If necessary, additives such as antifoaming agents and antioxidants may be added, and the amount of these additives used is about 0.1% or less based on the cleaning agent. The cleaning agent of the present invention has great significance when applied to activated rosin flux for assembly.

The following means are employed to bring the cleaning agent of the present invention into contact with the rosin flux on the substrate. That is, the cleaning agent consisting of the glycol ether compound, hydrocarbon compound, and optionally a nonionic surfactant, which are the active ingredients of the present invention, is used as is or diluted with water, and the concentration of the active ingredient is usually less than 100% by weight. Adjust to about 10% by weight.

A method of washing the substrate by directly immersing it in the thus obtained aqueous dispersion or the active ingredient itself, a method of flushing the aqueous solution using a spray device, or a method of washing while brushing by mechanical means may be selected as appropriate. can be adopted. Conditions for applying the cleaning agent of the present invention may be appropriately selected depending on the concentration of the active ingredient in the cleaning agent, the usage ratio of the ingredient, the type of flux to be removed, etc. Generally, the flux to be removed is cleaned. Contact the cleaning agent with the flux at a temperature and time effective to remove it. The temperature during use of the cleaning agent is about room temperature to about 80°C, and usually preferably about 50 to 70°C. When removing solder flux on a substrate by a dipping method at a temperature of about 60° C., for example, the solder flux can be removed satisfactorily by immersing the substrate with solder flux in the cleaning agent of the present invention for about 1 to 5 minutes. I can do it.

The substrate from which the flux has been removed is preferably cleaned as a finishing treatment using water or soapy water containing a nonionic surfactant to completely remove any cleaning agent that may remain. Such water washing treatment makes the substrate extremely clean.

Therefore, the cleaning agent of the present invention exhibits a flux cleaning effect similar to or superior to that obtained when conventional halogenated hydrocarbon-based cleaning agents are used, and achieves a high level of substrate cleaning.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited only to these examples.

Example 1 A cleaning agent of the present invention was prepared by mixing 50 parts by weight of diethylene glycol dimethyl ether and 50 parts by weight of decane.

On the other hand, apply 20 gin-based flux (manufactured by LONCO, trade name: Re5in) to the entire surface of the printed wiring board (copper-clad laminate).
Flux #77-25 J) was applied and heated to 130°C.
After drying for 2 minutes at 260° C., solder flow was performed at 260° C. for 5 seconds to prepare a test board.

This substrate was immersed in the above cleaning agent at room temperature, and the degree of flux removal was visually evaluated based on the following criteria. The results are shown in Table 1.

○ Can be removed well △ Slightly remaining × Significantly remaining Next, after washing and drying the above board, using Omegameter 6005E (manufactured by KENKO, trade name),
The cleanliness (residual ion concentration) of the substrate was measured. The results are shown in Table 1.

Examples 2 to 11 Evaluations were conducted in the same manner as in Example 1, except that at least one of the cleaning agent composition and the immersion temperature during cleaning was changed as shown in Table 1. The results are shown in Table 1.

Example 12 45 parts by weight of diethylene glycol dimethyl ether, 45 parts by weight of decane and a polyethylene glycol alkyl ether type nonionic surfactant (manufactured by Dai Kogyo Seiyaku ■, trade name [Neuken ET-135J, -6 In formula (2), R4 has 12 carbon atoms ~14 branched alkyl groups, n is 9
A cleaning agent of the present invention was prepared by mixing 10 parts by weight. Next, the cleaning agent was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Examples 13 to 16 Evaluations were carried out in the same manner as in Example 1, except that at least one of the detergent composition and the type of surfactant used was changed as shown in Table 1. The result is the first
Shown in the table.

In Table 1, the surfactants used are as follows.

1 Neugen EA-12DJ (manufactured by Daiichi Kogyo Seiyaku ■, polyethylene glycol nonylphenyl ether type nonionic surfactant, - In Funagura (2), R' is a nonylphenyl group, and n is 5), [Neugen EA-
143J (manufactured by Daiichi Kogyo Seiyaku ■, polyethylene glycol decylphenyl ether type nonionic surfactant, - In Funagura (2), R4 is a dodecylphenyl group and n is IO) [Solken TW20J (Daiichi Kogyo Seiyaku) Polyoxyethylene sorbitan monolaurate, average number of added moles of ethylene oxide 12) manufactured by ■, Evan 420J (manufactured by Daiichi Kogyo Seiyaku ■, polyoxyethylene polyoxypropylene block polymer [hereinafter referred to as margins] (Effects of the present invention) According to the invention, the following effects are achieved.

(1) Since the cleaning agent of the present invention is a non-halogen cleaning agent, it does not cause the problem of ozone layer depletion that occurs with fluorocarbon cleaning agents.

(2) Since the cleaning agent of the present invention contains the glycol ether compound, it itself has a flash point in the absence of water, but the flash point of the compound is about 70°C. Since it belongs to the third class of petroleum as defined in the Japanese Fire Service Act, there is no need to use a special explosion-proof cleaning device when using it. Commercially available cleaning equipment can be easily used as is or by slightly modifying the specifications.

(3) When the cleaning agent of the present invention is used after being diluted with water,
It is possible to reduce the risk of ignition of the cleaning agent, to lower the cost of the cleaning agent, and to significantly reduce the wastewater treatment load, while maintaining sufficient cleaning power.

(4) The cleaning agent of the present invention has very little odor and is also satisfactory in this respect.

As described above, the present invention provides a non-halogen solder flux cleaning agent that has excellent cleaning power and is sufficiently free from environmental damage, flammability, and odor, and a solder flux using the cleaning agent. A cleaning method is provided.

Arakawa Chemical Industry Co., Ltd.

Claims (6)

[Claims] (1) General formula (1): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R^2 is a Alkyl group, R^3 represents a hydrogen atom or methyl group, m represents an integer from 2 to 4)
A rosin-based solder flux cleaning agent containing as an active ingredient a mixture of at least one glycol ether compound represented by the following and a hydrocarbon compound having 8 to 14 carbon atoms. (2) The glycol ether compound and carbon number 8 to 1
The proportion of hydrocarbon compounds used in No. 4 is 10 to 90% by weight in order.
The cleaning agent according to claim 1, wherein: 90 to 10% by weight. (3) General formula (1): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R^2 is a Alkyl group, R^3 represents a hydrogen atom or methyl group, m represents an integer from 2 to 4)
Cleaning of rosin-based solder flux characterized by containing as an active ingredient a mixture consisting of at least one of the glycol ether compounds represented by, a hydrocarbon compound having 8 to 14 carbon atoms, and a nonionic surfactant. agent. (4) The glycol ether compound and carbon number 8 to 1
4. The cleaning agent according to claim 3, wherein the proportions of the hydrocarbon compound (4) and the nonionic surfactant used are, in order, 10 to 80% by weight: 90 to 20% by weight: less than 30% by weight. (5) The nonionic surfactant has the general formula (2): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R is a straight or branched alkyl group having 5 to 20 carbon atoms, a phenyl group, or a phenyl group substituted with a linear or branched alkyl group having 7 to 12 carbon atoms, n is an integer of 5 to 20). Cleaning agents listed in . (6) A method for cleaning rosin-based solder flux, which comprises bringing the cleaning agent according to any one of claims 1 to 5 into contact with rosin-based solder flux.