JPH07197095A - Detergent composition for rosin flux - Google Patents

Abstract

PURPOSE:To obtain a detergent composition not causing environmental pollution such as depletion of the ozonosphere, being safe to the human body and having excellent power of deterging a rosin flux by using a specified amount of a specified monoterpenephenol. CONSTITUTION:This detergent composition contains 30-70wt.% of a monoterpenephenol of formula I (wherein R is a monocyclic terpene group) and/or a monoterpenephenol of formula II. It is desirable that this composition further contains 30-70wt.% nonionic surfactant of an HLB of 8-15. This composition further contains optionally 0-15wt.% at least one fully hydrogenated monocyclic terpene selected from among pinane, menthane, cineol, dihydroterpineol, menthol, dihydroterpinyl acetate and isobornyl acetate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning composition used for removing solder flux and rosin flux from a printed circuit board.

[0002]

2. Description of the Related Art When an electric component such as QFP is surface-mounted on a printed circuit board by soldering, it is possible to melt the oxide on the contact surface, improve the solder wettability, and improve the solder surface during soldering. Flux is used to prevent oxidation. Of these, rosin-based flux is widely used. If this rosin-based flux remains on the printed circuit board after soldering, not only will the electrical characteristics such as the insulation resistance and dielectric properties of the circuit deteriorate, but there will also be poor contact during in-circuit testing and adhesion of coating resin. There are problems such as defectiveness, poor appearance, and stickiness. Therefore, the flux remaining after soldering has been removed using a cleaning agent.

Conventionally, halogenated hydrocarbon solvents such as trichloroethylene, 1,1,1-trichloroethane, and CFC 113 have been used as the cleaning liquid. In particular, CFC 113 has been widely used because of its nonflammability, low toxicity, and excellent chemical stability. More recently, in U.S. Pat. Nos. 4,511,488 and 4,640,719, α-pinene, β-pinene, γ-terpinene, Δ
There has been proposed a cleaning agent containing an emulsified cleaning agent for flux containing a monoterpene such as 3-carene, limonene and ditenpen in a weight ratio of 0 to 40% relative to the monoterpene. In addition, Japanese Patent Laid-Open No. 4-13019
No. 9 discloses terpene alcohols such as linaol, geraniol, citroneol, α-, β-, γ-terpineol, menthol and cineol with 0.5 to 0.5%.
A detergent containing 20% by weight of a nonionic or anionic surfactant has been proposed.

[0004]

The halogenated hydrocarbon solvents that have been used in the past have been regulated for use due to environmental destruction such as ozone depletion. Furthermore, problems such as safety for the human body have been pointed out. On the other hand, a detergent comprising terpene or terpene alcohol and a surfactant has good detergency, human safety and microbial degradability. However, the terpene compound described in U.S. Pat. No. 4,511,488 is highly dangerous because it has a low flash point, and further has a great influence on the mounted electric parts, which may deteriorate the electric characteristics of the parts. There are problems such as some. Further, in JP-A-4-130199, since the content of the terpene or terpene alcohol is 80% or more, the terpene or terpene alcohol attached in the rinsing step cannot be dissolved in water and easily remains on the printed circuit board. There is a problem that the electrical characteristics of the circuit may be deteriorated and the odor is strong.

The present invention solves the above problems and, in removing the solder flux and rosin flux from the printed circuit board, not only has no environmental pollution and is good for human safety, but also has good electrical characteristics. It is an object of the present invention to provide a cleaning composition for rosin-based flux, which is less affected by water and has high water rinsing properties.

[0006]

Means and Actions for Solving the Problems The detergent composition of the present invention contains monoterpene phenols represented by Chemical formulas 3 and 4 as essential components.

[0007]

[Chemical 3]

[0008]

[Chemical 4]

The monoterpene phenols represented by the chemical formulas 3 and 4 are produced by chemically reacting a monocyclic terpene and phenol, but there are many kinds by changing the monocyclic terpene to be reacted. In the compound of Chemical formula 3, there exists an isomer in which a monocyclic terpene is added to the ortho, meta, and para positions with respect to phenol, but the para position is most easily synthesized because of steric hindrance or the like. The compound of Chemical formula 3 has the property of being easier to synthesize than the compound of Chemical formula 4.

Specific examples of the monoterpene phenols applicable to the present invention include those having the structures of Chemical formula 5, Chemical formula 6, and Chemical formula 7, but are not limited thereto, and The terpene phenols may be used alone or in combination of two or more.

[0011]

[Chemical 5]

[0012]

[Chemical 6]

[0013]

[Chemical 7]

Although the monoterpene phenols differ depending on the monocyclic terpene to be reacted, the cleaning power of the rosin-based flux is excellent overall and the flammability is lower than that of the monocyclic terpene. It also has less odor than monocyclic terpenes. The larger the amount added, the better the cleaning performance.
If the content is too large, the rinsing property with water is lowered and there is a risk of remaining on the substrate, so 30 to 70% by weight is appropriate.

Further, the present invention may contain 30 to 70% by weight of a nonionic surfactant having an HLB value of 8 to 15. Since monoterpene phenols are hardly dissolved in water, when the cleaning liquid is composed of only monoterpene phenols, it becomes impossible to rinse the cleaning agent with water after cleaning, so that it is added. If this surfactant is added in a small amount, the monoterpene phenols cannot be solubilized or emulsified. Also, if too much, the rinsing process may be lengthened and may remain on the substrate.
0 to 70% by weight is suitable. The nonionic surfactant is not particularly limited as long as it can solubilize or emulsify the monoterpene phenols, and known surfactants can be used. However, rinsing property in water and dissolved state,
A nonionic surfactant having an HLB value of 8 to 15 is preferable for reasons such as the effect on the object to be cleaned and the effect on the electric circuit when it remains. Specifically, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene polypropylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycol fatty acid ester, polyoxyethylene alkylamine, polyglycerin fatty acid ester, etc. There is.

Further, the present invention comprises a completely hydrogenated monocyclic terpene selected from pinane, menthane, cineol, dihydroterpineol, menthol, dihydroterpinyl acetate, isobornyl acetate and menthyl acetate, alone or in a mixture. May be. The fully hydrogenated monocyclic terpenes are added for the purpose of adjusting the viscosity of the washing liquid or diluting the monoterpene phenols. The optimum amount of this addition is 0 to 15% by weight, and if it is more than that, flammability is increased and odor is increased, which is not preferable. Further, the cleaning composition of the present invention, as long as the effect is not impaired, higher alcohol and glycol ether,
A small amount of rust preventive agent, antioxidant, antifoaming agent, etc. may be added.

The detergent composition of the present invention exhibits excellent performance particularly in removing rosin-based flux from a printed circuit board. As the cleaning method, various cleaning methods such as a dipping method, a rocking method, an ultrasonic vibration method, a shower cleaning method, and a submerged jet method can be used.

The flux removal using the cleaning composition of the present invention is carried out, for example, by shower cleaning with this cleaning composition, followed by ultrasonic cleaning in a cleaning tank filled with this cleaning composition, and further, This can be easily performed by rinsing with water or an organic solvent such as alcohol or glycol ether and then drying with hot air.

[0019]

The present invention is described in detail below with reference to examples, but the present invention is not limited thereto. A cleaning liquid having the composition shown below was prepared, and the cleaning property and water rinsing property were evaluated. The evaluation items and criteria are as follows. The results are shown in Table 1.

[0020]

[Table 1]

A. Flux cleanability A rosin-based flux was applied to a 5-inch square checkered copper plate with a fluxer and subjected to a normal solder dip treatment. This copper plate was cleaned with a cleaning liquid having a liquid temperature of 60 ° C. for 3 minutes by ultrasonic waves at 25 kHz. In addition, pure water at a liquid temperature of 30 ° C for 25 minutes for 3 minutes
Rinsing was performed with ultrasonic waves of kHz, and the amount was determined by the amount of flux residue when dried at 80 ° C. for 5 minutes. "○" indicates that there is almost no flux residue, "△" indicates that there is some flux residue, and "x" indicates that there is considerable flux residue.

B. Water rinsing property It was judged by the rinse condition when the epoxy plate immersed in the cleaning solution was shower rinsed with water for 3 minutes. "○" indicates a good rinse, "△" indicates a little bad, and "x" indicates a bad one.

(Composition of Example 1) Compound shown in Chemical formula 5 35% Polyoxyethylene lauryl ether 50% Menthane 5% Water 10%

(Composition of Example 2) Compound represented by Chemical formula 6 40% Polyoxyethylene octyl phenyl ether 40% Dihydroterpineol 15% Water 5%

(Composition of Example 3) Compound represented by Chemical formula 7 30% Polyoxyethylene polypropylene ether 55% Pinane 10% Dihydroterpinyl acetate 5%

(Composition of Comparative Example 1) d-Limonene 90% Polyoxyethylene lauryl ether 10%

(Composition of Comparative Example 2) α-Terpineol 80% Polyoxyethylene lauryl ether 20%

[0028]

EFFECTS OF THE INVENTION The cleaning composition of the present invention has no environmental pollution such as ozone layer depletion, is safe for humans, has excellent rosin-based flux cleaning properties, and has excellent water rinsing properties, and affects electrical parts. Has less characteristics.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H05K 3/26 7511-4E // (C11D 10/02 1:72 3:20 3:18)

Claims (4)

[Claims] 1. A cleaning composition for a rosin flux, which comprises 30 to 70% by weight of the monoterpene phenols represented by Chemical Formula 1 or Chemical Formula 2 alone or in a mixture. [Chemical 1] [Chemical 2] 2. The compound according to claim 1 has an HLB value of 8
15 to 15% by weight of the nonionic surfactant is contained in an amount of 30 to 70% by weight. 3. The compound according to claim 1 or the compound according to claim 2, which is a fully hydrogenated monocyclic compound selected from pinane, menthane, cineol, dihydroterpineol, menthol, dihydroterpinyl acetate and isobornyl acetate. A rosin-based flux cleaner composition comprising terpenes alone or in a mixture of two or more kinds in an amount of 0 to 15% by weight. 4. A cleaning composition for rosin flux, wherein the compound according to claim 1 contains 0 to 15% by weight of water.