JP2979291B2 - Recycling detergent composition and method for regenerating the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the cleaning of various processing oils and solder fluxes (hereinafter referred to as fluxes) in the process of manufacturing machine parts, printed boards, printed wiring boards, lead frames, and the like. More specifically, the cleaning composition to be used is excellent in detergency, does not change its composition even when regenerated by distillation, and can be used stably without causing corrosion or discoloration of an object to be cleaned. ,
And a reproduction method thereof.

[0002]

2. Description of the Related Art Conventionally, chlorine-based cleaning agents and chlorofluorocarbon-based cleaning agents have been used for cleaning various processing oils and fluxes.
However, with the rise of global natural environment preservation consciousness, the development of alternative detergents and the conversion to them have been promoted.

As these alternative detergents, for example, an aqueous detergent using a surfactant and a non-aqueous detergent using an organic solvent are known. As non-aqueous detergents, for example, halogen-based detergents described in JP-A-1-152200 and terpene compounds disclosed in JP-T-63-501908 are known. Although has high detergency, there is concern about biotoxicity or environmental pollution due to penetration into the ground, while the latter is a natural product, and its quality, supply and cost are unstable. Therefore, in recent years, among non-aqueous detergents, demand for hydrocarbon-based detergents obtained by distillation, synthesis, and the like from petroleum-based raw materials has been rapidly increasing.

[0004] Hydrocarbon-based cleaning agents have the same detergency against various processing oils as press oils, drawing oils, cutting oils, and the like, as compared with conventional chlorine-based cleaning agents and CFC-based cleaning agents. However, the flux used in the soldering process was not sufficiently clean. Therefore, in order to sufficiently cope with such flux cleaning, a cleaning agent in which various polar compounds are mixed with a hydrocarbon-based cleaning agent is being studied.For example, alcohols, glycol ethers, esters, and the like are mixed. Hydrocarbon-based cleaning agents (for example, JP-A-3-146597, JP-A-5-
140593, JP-A-5-263099, JP-A-7
-268391).

[0005] However, when the multi-component detergent to which the polar compound is added as described above is regenerated by distillation for the purpose of recycling, the hydrocarbon as the base material and the polar compound are not necessarily distilled off at the same time. Therefore, at the time of recycling, it is necessary to adjust the concentration of the polar compound in the regenerated detergent as described in JP-A-5-263099, which makes the liquid management complicated. There was a problem.

When the hydrocarbon-based cleaning agent is recycled by distillation as described above, after several times of recycling,
It is known that a hydrocarbon-based cleaning agent which is originally considered to be stable is oxidatively degraded by heating, and an acidic substance such as a free acid or a peroxide which causes corrosion or discoloration of an object to be cleaned is generated. It is also known that when a flux is mainly washed, an acidic halide or the like is taken into the cleaning agent. Therefore, in order to recycle the hydrocarbon-based detergent with stable properties, it can be said that it is necessary to prevent the generation of these acidic substances.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, an object of the present invention is to have a sufficient detergency for processing oil and flux, to have no change in composition even when recycled by distillation, and to control the liquid. An object of the present invention is to provide an easy-to-use cleaning agent and a method of regenerating a cleaning agent that can prevent generation of an acidic substance that affects an object to be cleaned during recycling.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, based on a saturated aliphatic hydrocarbon solvent having an extremely narrow boiling point range, The cleaning composition, in which alcohols azeotropic in a specific range are mixed with a substantially azeotropic composition, is very easy to regenerate by distillation, there is no change in composition even after recycling, and therefore, recycling without adjusting the liquid. The present inventors have found that it is possible to add a specific amino alcohol at the time of distillation regeneration, and it is possible to neutralize an acidic substance very effectively to prevent the generation thereof, thereby completing the present invention.

That is, the present invention contains a hydride of isobutene trimer and an alcohol selected from 2-ethyl-1-hexanol, 2-octanol and 1-heptanol, and the weight of the alcohol relative to the total weight of the mixture is determined. An azeotropic mixture is formed in the range of 8 to 18% by weight, and a composition ratio between the hydride of the isobutene trimer and the alcohol is substantially equal to an azeotropic composition. A cleaning composition is provided.

Further, the present invention provides a method of regenerating the cleaning composition for recycling by distillation, which has a boiling point of 240.
An object of the present invention is to provide a method for regenerating a detergent composition for recycling, characterized by adding 0.001 to 5% by weight of an amino alcohol having a temperature of at least 0 ° C to the detergent composition.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The hydrocarbon solvent used as the base material of the cleaning composition of the present invention comprises a saturated aliphatic hydrocarbon having 11 to 13 carbon atoms. Undecane, dodecane, tridecane in a chain or branched chain. These hydrocarbon solvents may be either a single solvent or a mixture, but need to have a boiling point range of 10 ° C or less, and preferably have a boiling point range of 5 ° C or less.
If the boiling point range is wider than this, it will be difficult to obtain an azeotrope having a constant composition with alcohols. In addition, the boiling point range referred to in the present invention refers to a temperature difference between a 5% distillation temperature and a 95% distillation temperature of a solvent.

In the present invention, the above-mentioned hydrocarbon solvent
Among them, isododecane is particularly preferred. This isododecane
Is obtained by pyrolyzing petroleum-based raw materials such as naphtha.
C _FourFrom the distillate (butene-butadiene fraction)
Is removed, and then isobutene is removed by a method such as sulfuric acid absorption.
The isobutene is then separated by extraction with an acid catalyst.
Polymerizes in the presence or absorbs isobutene in sulfuric acid
It is heated as it is, mainly from dimers, trimers and tetramers.
To obtain a multimer, which is distilled to separate a trimer.
Obtained by hydrogenating the olefin part of the monomer
Can be. The hydrogenation rate in this hydrogenation is as high as possible.
Is preferable, but the residual amount of the olefin is 5% by weight or less.
If it does not impair the performance of the cleaning agent of the present invention
Absent.

The isododecane thus produced is a mixture of isomers containing 2,2,4,6,6-pentamethylheptane as a main component, and has a very narrow boiling point range due to a small number of components. Further, it has excellent features such as extremely low odor and low toxicity, and can be used alone as a detergent. Even when used in combination with alcohols as in the present invention, the composition and azeotropic point of the azeotropic mixture are constant because the boiling point range is narrow, and the components are clear even when performing analysis such as gas chromatography. It has various advantages such as easy liquid management.

In the present invention, the alcohol mixed with the above-mentioned saturated aliphatic hydrocarbon solvent forms an azeotrope with the hydrocarbon solvent in the range of 5 to 25% by weight based on the total weight of the mixture. . As such alcohols, monohydric alcohols having 7 or 8 carbon atoms and a boiling point of about 150 to 220 ° C. are preferable. For example, 2-ethyl-1-hexanol, 2-octanol, 1-heptanol, 3
-Methyl-1-hexanol, 5-methyl-1-hexanol and the like. In the present invention, it is particularly preferable to use 2-ethyl-1-hexanol, 2-octanol or 1-heptanol.

The mixing amount of these alcohols needs to be an amount substantially equivalent to the azeotropic composition with the above-mentioned saturated aliphatic hydrocarbon solvent. However, it is not always necessary to mix the detergent before recycling with an azeotropic composition,
If the amount is in the vicinity of the azeotropic composition, there is no problem since the azeotropic composition will be obtained when distilled and recycled. For example, the hydrocarbon solvent is the above isododecane, and the alcohol is 2
In the case of -ethyl-1-hexanol, if it is mixed in an amount of 10 to 12% by weight with respect to the total weight of the mixture, it becomes an azeotropic composition of about 11% by weight after recycling and becomes constant. When the amount of the alcohol to be mixed is small, that is, when an alcohol having an azeotropic composition with a hydrocarbon solvent of less than 5% by weight is selected, sufficient detergency against the flux cannot be obtained, and conversely, the amount is large. In the case, that is, when an alcohol having an azeotropic composition with a hydrocarbon solvent exceeding 25% by weight is selected, a problem of rusting of the object to be cleaned occurs due to a large amount of water in the cleaning agent, In addition, alcohols are more expensive than hydrocarbon solvents, which leads to an increase in the cost of the cleaning agent, which is not preferable. The above isododecane was used as the hydrocarbon solvent, and the alcohols were 2-
Ethyl-1-hexanol, 2-octanol or 1
-When any one of heptanol is selected, the amount of the alcohol mixed becomes 8 to 18% by weight from the azeotropic composition thereof.

The detergent composition of the present invention obtained as described above has a high detergency against various processing oils and fluxes, and since it is an azeotropic mixture, its composition changes even after distillation and regeneration. It can be recycled without complicated liquid management such as adjustment of alcohol concentration.

The present invention further provides a method for regenerating a cleaning composition based on such a hydrocarbon solvent.
As described above, the hydrocarbon-based cleaning agent contains various acidic substances during use. In the regeneration method of the present invention, for the purpose of neutralizing such acidic substances and preventing the generation, Amino alcohols are added in the step of distillation and regeneration of the detergent.

Here, the type of amino alcohols used is not particularly limited, but if the boiling point is lower than that of the detergent composition, the alcohol is distilled off together with the detergent composition at the time of regenerating by distillation, and this is the odor of the detergent composition. In some cases, amino alcohols having a boiling point of 240 ° C. or more at normal pressure are preferably used because they may affect the cleaning object in some cases. Examples of such amino alcohols include diethanolamine (boiling point: 269 ° C./760 mmHg),
Triethanolamine (boiling point: 360 ° C./760 mmHg) can be mentioned.

The amount of the amino alcohol added to the cleaning composition is not specified because it depends on the type of soil to be cleaned and the degree of soiling of the cleaning composition to be regenerated. 0.001 to 5% by weight, preferably 0.01 to 1% by weight. If the addition amount is less than this range, a sufficient effect on neutralization of the acidic substance cannot be obtained, and if it exceeds this range, the effect does not change and only the cost is increased.

The method of adding amino alcohols to the detergent composition may be carried out during the supply of the used detergent composition to the distillation regeneration device or directly at the bottom of the regeneration device. When the machine is of a multi-tank type such as a rough washing and a rinsing washing, a method of adding to a rough washing tank may be used.

The distillation column used in the distillation for regeneration may be of a multistage type, a packed type or the like, but a simple distillation is usually sufficient. The pressure at this time may be normal pressure,
Since the boiling point of the cleaning agent is relatively high, it is desirable that the cleaning be performed under reduced pressure of, for example, 100 mmHg or less. The overhead temperature during distillation is 150 ° C. or less when the operation is performed under reduced pressure as described above,
For example, in the case of the above-mentioned azeotrope of isododecane and 2-ethyl-1-hexanol, 100 ° C. (75 mmHg) to 1 ° C.
05 ° C (85 mmHg). The type of distillation may be batch, semi-batch or continuous. The recovery amount of the cleaning composition by such distillation depends on the degree of contamination of the cleaning composition, but is usually about 80 to 95% by weight of the supplied amount.

The method for regenerating the cleaning composition of the present invention is not applied only to the cleaning composition provided by the present invention, but widely uses a saturated aliphatic hydrocarbon as a base material. This is effective when the detergent is distilled and recycled.

Machine parts using the cleaning composition of the present invention,
When cleaning printed circuit boards, printed wiring boards, lead frames, etc., immerse the object to be cleaned in the cleaning composition,
Further, if necessary, a commonly known cleaning method, that is, ultrasonic cleaning, mechanical stirring, shaking, shaking, bubbling with a nonflammable gas such as nitrogen gas, liquid flow, or the like may be used in combination. Since the cleaning composition of the present invention is a flammable liquid having a flash point, it is usually desirable to use it in a closed and closed system at a temperature lower than the flash point (about 50 to 60 ° C.) of the cleaning agent. Other than the above, there is no particular limitation on the cleaning method applied when using the cleaning composition of the present invention.

[0024]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 Butadiene was removed from the C ₄ fraction by-produced in the production of ethylene and propylene by pyrolysis of naphtha, and then isobutene was absorbed and separated with 63% sulfuric acid. Is heated to 2
A polymerization solution consisting of a dimer, trimer and tetramer was obtained, and this was purified by distillation to obtain a trimer of isobutene. Next, using a nickel-based catalyst, the reaction temperature was 160 ° C. and the pressure was 40 kg / cm ^2.
G Hydrogenates the olefin portion under the conditions of 3 hours to obtain a hydride of isobutene trimer (hereinafter referred to as isododecane)
I got This product has a hydrogenation rate of 99% or more and 5%
The distillation temperature was 177.9 ° C, and the 95% distillation temperature was 179.0 ° C.

Next, the azeotropic composition of isododecane and 2-ethyl-1-hexanol (manufactured by Kyowa Yuka Co., Ltd., purity 99.9%, hereinafter referred to as EHA) was examined using an Osmer equilibrium distillation apparatus. Was. As a result, the composition ratio of isododecane was 8
The composition ratio of EHA was 9% by weight and 11% by weight. Less than,
This composition is referred to as Cleaning Agent A.

Example 2 The azeotropic composition of isododecane obtained in the same manner as in Example 1 and 2-octanol (reagent first grade, manufactured by Kanto Chemical Co., Ltd.) was examined in the same manner as in Example 1. As a result, the composition ratio of isododecane was 87% by weight, and the composition ratio of 2-octanol was 13% by weight. Hereinafter, this composition is referred to as a detergent B.

Example 3 The azeotropic composition of isododecane obtained in the same manner as in Example 1 and 1-heptanol (first grade reagent, manufactured by Kanto Chemical Co., Ltd.) was examined in the same manner as in Example 1. As a result, the composition ratio of isododecane was 85% by weight, and the composition ratio of 1-heptanol was 15% by weight. Hereinafter, this composition is referred to as a detergent C.

Examples 4 to 6 and Comparative Example 1 Processing oil (Cosmo Press B202, manufactured by Cosmo Oil Co., Ltd.)
And flux (Tamura Kaken Co., Ltd., F-230
V) was weighed for each copper piece (0.2 × 20 ×
70 mm) and applied to the cleaning agent A obtained in Example 1, the cleaning agent B obtained in Example 2, and the cleaning agent C obtained in Example 3.
The solution was immersed in 1 liter of isododecane alone and gently stirred at room temperature for 5 minutes. Thereafter, the copper pieces were pulled up, dried at 40 ° C. for 25 minutes, and the weight increase of the copper pieces was measured to evaluate the detergency of each cleaning agent against processing oil and flux. Table 1 shows the results.

[0030]

[Table 1]

From the table, it can be seen that isododecane alone has a slightly insufficient detergency against flux, but the cleaning agents A, B and C of the present invention have sufficient detergency against both processing oil and flux. It can be seen that

Comparative Example 2 To 500 ml of the cleaning agent A obtained in Example 1, 1 g of the same processing oil and flux as those used in Example 4 were added, and heated at 120 ° C. for 5 hours. Thereafter, the detergent A was recovered from the mixture by simple distillation under a reduced pressure of 75 mmHg. Distillation was stopped when the collected liquid reached about 450 ml,
The obtained recovered liquid is subjected to a copper plate discoloration test (JIS K
2513) and acid content measurement (JIS K 007)
0). Thereafter, a new detergent A was added to the recovered liquid to make the total volume 500 ml, and the same operation as above was performed. This recycling was repeated five times. Note that 120
The heating operation at 5 ° C. for 5 hours is irrelevant to the actual cleaning process, but is performed to make the effect of the oxidative deterioration of the cleaning agent remarkable. Table 2 shows the results of the above tests and measurements.
Shown in

[0033]

[Table 2]

From the same table, it can be seen that the acid content of the cleaning agent regenerated by the above-mentioned method increases when recycle is repeated, thereby causing discoloration of the copper pieces.

Examples 7-8 0.38 g of triethanolamine (boiling point: 360 ° C.) or diethanolamine (boiling point: 269 ° C.) during distillation
(0.1% by weight with respect to the detergent), and the same operation as in Comparative Example 2 was performed. The results are shown in Table 2. From the table, it can be seen that the addition of triethanolamine or diethanolamine during distillation can prevent the generation of an acid component in the cleaning agent, and the regenerated cleaning agent does not cause copper plate discoloration even if recycling is repeated.

[0036]

By using the cleaning composition of the present invention, excellent effects can be obtained for cleaning processing oils and fluxes without using so-called halogen-based solvents such as fluorocarbons and chlorine. Even when recycled, there is no change in composition, and liquid management is easy. Further, according to the method for regenerating the cleaning composition of the present invention, generation of acidic substances in the cleaning agent, which has conventionally been a problem with hydrocarbon-based cleaning agents, can be efficiently prevented.

Claims (3)

(57) [Claims] 1. A hydride of isobutene trimer, and 2
-Ethyl-1-hexanol, 2-octanol and 1
-Containing an alcohol selected from heptanol, wherein the weight of the alcohol is 8 to 18% by weight based on the total weight of the mixture.
A azeotrope in the range described above, and wherein the composition ratio between the hydride of the isobutene trimer and the alcohols is substantially equal to the azeotropic composition. 2. The step of regenerating the cleaning composition according to claim 1 by distillation, wherein the boiling point is 240.
A method for regenerating a detergent composition for recycling, characterized by adding 0.001 to 5% by weight of an amino alcohol having a temperature of at least 0 ° C to the detergent composition. 3. The method according to claim 2, wherein the amino alcohol is diethanolamine or triethanolamine.