JP2003041297A - Detergent and washing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detergent and a washing method which give a detergency, dryness and the like that can compete with a washing in which a fluorocarbon-based solvent and the like are employed. SOLUTION: The detergent is a mixture of an azeotropic or pseudoazeotropic composition which comprises a low-molecular siloxane compound and a 4-30C aliphatic hydrocarbon solvent, or comprises a low-molecular siloxane compound and a 4-30C alicyclic hydrocarbon-based solvent, with which washing to drying can be carried out in one liquid. The low-molecular siloxane compound may include at least one low-molecular-weight polyorganosiloxane selected from a straight-chain polydiorganosiloxane and a cyclic polydiorganosiloxane. The aliphatic hydrocarbon-based solvent may include a volatile isoparaffin-based solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning agent and a cleaning method, and more particularly to a non-aqueous one-liquid cleaning agent and a one-liquid cleaning method using this cleaning agent.

[0002]

2. Description of the Related Art As a cleaning agent for removing oil stains on metal parts, plated parts, painted parts, electronic parts, semiconductor parts, etc., conventionally, a chlorofluorocarbon solvent represented by Freon 113, trichloroethane, trichloroethylene, Chlorine-based organic solvents such as tetrachloroethylene and carbon tetrachloride are used.

Recently, however, it has been revealed that the release of CFCs leads to the destruction of the ozone layer and seriously affects the human body and biological systems. , It is gradually reducing its use on a global scale, and in the future it is going to be totally abolished. In addition, chlorine-based organic solvents such as trichlorethylene and tetrachloroethylene are also in the direction of being tightened due to environmental problems such as pollution of soil and groundwater.

In addition, volatile solvents of aliphatic hydrocarbon type such as isoparaffin type and alicyclic hydrocarbon type such as cycloparaffin type have been conventionally used for washing machine oil adhered to metal parts. However, the use of these solvents has the following problems.

That is, these volatile solvents used in the cleaning apparatus are a mixture of components having various boiling points, which are distilled and refined from petroleum, and contain high boiling components having a large latent heat of vaporization, so that they are dried. Not only does it take a long time, but there is also a problem that high-boiling components remain on the surface of the object to be cleaned during drying and stains are likely to occur.

[0006]

As described above, among the conventional cleaning agents, the CFC-based organic solvent and chlorine-based organic solvent-based cleaning agents have a serious drawback of causing environmental damage. In addition, the current detergents that have been investigated as alternatives to these have a problem that sufficient effects cannot be obtained.

Further, it takes time to dry with an aliphatic hydrocarbon solvent such as an isoparaffinic solvent or an alicyclic hydrocarbon solvent such as a cycloparaffinic solvent which has been conventionally used for cleaning oil stains such as machine oil. In addition, there is a problem that dry spots are likely to remain on the surface of the object to be cleaned.

The present invention has been made to address the problems associated with the above-described conventional cleaning agents and cleaning methods, and is excellent in quick-drying properties and does not cause dry spots on the surface of the object to be cleaned. Moreover, it is an object of the present invention to provide an environment-friendly cleaning agent and a cleaning method that do not destroy the ozone layer.

[0009]

The detergent of the present invention has an azeotropic composition comprising a low-molecular siloxane compound and an aliphatic hydrocarbon solvent having 4 to 30 carbon atoms, as described in claim 1. It is characterized by being a mixture having a pseudo-azeotropic composition. Further, as described in claim 4, it is a mixture of an azeotropic composition or a pseudo-azeotropic composition containing a low molecular siloxane compound and an alicyclic hydrocarbon solvent having 4 to 30 carbon atoms. .

As described in claim 9, the cleaning method of the present invention uses a mixture of an azeotropic composition or a pseudo-azeotropic composition which comprises a low molecular weight siloxane compound and an isoparaffinic solvent having 4 to 30 carbon atoms. It is characterized in that a series of steps from cleaning to drying is performed with one liquid. Further, as described in claim 10, a low-molecular-weight siloxane compound and a carbon number 4
It is characterized in that a series of steps from washing to drying is carried out by one liquid by using a mixture of an azeotropic composition or a pseudo-azeotropic composition containing 30 to 30 cycloparaffinic solvents.

The low molecular weight siloxane compound used in the cleaning agent and cleaning method of the present invention has a general formula:

[Chemical 5] (In the formula, R is the same or different and is substituted or unsubstituted 1
A valent hydrocarbon group, l represents an integer of 0 to 5), and a linear polydiorganosiloxane represented by the general formula:

[Chemical 6] (In the formula, R is the same or different and is substituted or unsubstituted 1
And at least one low molecular weight polyorganosiloxane selected from cyclic polydiorganosiloxanes represented by a valent hydrocarbon group, m is an integer of 3 to 7).
The linear polydiorganosiloxane represented by the formula (1) and the cyclic polydiorganosiloxane represented by the formula (2) can be used in combination.

R in the above formulas (1) and (2) is a substituted or unsubstituted monovalent hydrocarbon group, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a phenyl group. Examples thereof include monovalent unsubstituted hydrocarbon groups such as groups, and monovalent substituted hydrocarbon groups such as trifluoromethyl groups. A methyl group is most preferable from the viewpoints of stability of the system, maintenance of volatility, and the like.

Specific examples of the low molecular weight polyorganosiloxane include hexamethyldisiloxane (M2), octamethyltrisiloxane (MDM), decamethyltetrasiloxane (MD2M), hexamethylcyclotrisiloxane (D3) and octamethyl. Cyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5),
Examples thereof include dodecamethylcyclohexasiloxane (D6). Particularly, octamethylcyclotetrasiloxane (D4) is preferable.

Such a low-molecular-weight siloxane compound does not destroy the ozone layer, has a low surface tension and a low viscosity, and therefore has excellent penetrability into gaps, and also has a low latent heat of vaporization, and thus has excellent drying characteristics. There is.

The aliphatic hydrocarbon solvent used in the cleaning agent and the cleaning method of the present invention is a branched or straight chain aliphatic hydrocarbon having 4 to 30 carbon atoms (hereinafter, simply referred to as an aliphatic hydrocarbon solvent). )), For example, an isoparaffinic solvent. That is, the isoparaffin-based solvent is used as one kind or a mixture of two or more kinds of volatile isoparaffins, and as the volatile isoparaffin, particularly C _{4 to} C
Isoparaffin, which is mainly composed of ₁₆ fractions, is preferable from the viewpoint of cleaning performance and handling in a cleaning device. Furthermore, it is preferable to use paraffinic hydrocarbons having 8 to 15 carbon atoms, including such isoparaffins.

When the aliphatic hydrocarbon solvent has less than 8 carbon atoms, its flash point becomes low. Therefore, when safety is important, it is desirable that the aliphatic hydrocarbon solvent has 8 or more carbon atoms. When the carbon number exceeds 16, the boiling point becomes high, making it difficult to use warm air drying under normal pressure.

The alicyclic hydrocarbon solvent used in the cleaning agent and the cleaning method of the present invention has a carbon number of 4 to 30, and is a saturated cyclic hydrocarbon (hereinafter, simply referred to as an alicyclic hydrocarbon) connected by a single bond of carbon. It is described as a cyclic hydrocarbon solvent). For example, a cycloparaffinic solvent may be used. That is, the cycloparaffinic solvent is used as one kind or a mixture of two or more kinds of volatile cycloparaffins, and as the volatile cycloparaffins, cycloparaffins mainly composed of C _{4 to} C ₁₆ fractions are washed. It is preferable in terms of performance and handling in a cleaning device.

Further, in the present invention, a solvent containing such a cycloparaffin as a main component and containing a paraffinic hydrocarbon having 8 to 15 carbon atoms or an isoparaffinic hydrocarbon can also be used. That is, most of the available alicyclic hydrocarbon solvents are mixed solvents in which alicyclic hydrocarbons and aliphatic hydrocarbons are mixed in the production method, but such mixed solvents can also be used. .

The detergent of the present invention has the above-mentioned carbon number of 4 to 30.
A mixture of an azeotropic or pseudo-azeotropic composition consisting of an aliphatic hydrocarbon solvent and a low-molecular-weight siloxane compound, or a mixture containing the alicyclic hydrocarbon solvent having 4 to 30 carbon atoms and a low-molecular-weight siloxane compound. It is a mixture of azeotropic or pseudoazeotropic compositions.

Here, the azeotropic mixture is a mixture having a liquid phase composition and a gas phase composition which can be distilled without changing the composition. Although not forming an azeotropic mixture, in the boiling point diagram represented by the temperature-composition, when the boiling curve and the condensation curve are close to each other, when the volatility of each component is close, the boiling points of each component are close to each other. A phenomenon in which the composition of the liquid phase and the composition of the gas phase are similar to each other is called pseudo-azeotrope, and the mixture forming such pseudo-azeotrope is called pseudo-azeotropic mixture.

The azeotropic property (including pseudo-azeotropic property) is exhibited when the boiling point of the mixture becomes lower or higher than the intrinsic boiling point of each component. Therefore, the azeotropic property is often not obtained simply by mixing the respective components, and when the boiling point of the mixture becomes lower than the specific boiling point of each component, the liquid mixed at an arbitrary ratio is distilled, It can be obtained by repeatedly distilling the fraction or performing rectification with a plate number.

The azeotropic mixture of the low molecular weight siloxane compound and the aliphatic hydrocarbon solvent or the alicyclic hydrocarbon solvent in the present invention is obtained in this way, and the boiling point of the mixture is that of each component ( Low molecular weight siloxane compound and aliphatic hydrocarbon solvent or alicyclic hydrocarbon solvent)
Lower than the intrinsic boiling point of. Further, it is characterized in that even if distillation is repeated under a constant pressure, no substantial change in the fraction is observed.

In the cleaning method of the present invention, the above-mentioned mixture having an azeotropic composition is used to carry out a series of cleaning, rinsing and drying steps as one liquid. Here, the drying process includes warm air drying, natural drying, vacuum drying, or reduced pressure steam.
It can be performed by vacuum drying.

The objects to be cleaned which are objects of the present invention are metals, ceramics, plastics and the like, and more specifically, metal parts, surface treatment parts, electronic parts, semiconductor parts, electric parts, precision machine parts, optical parts. , Glass parts, ceramic parts, etc. Then, degreasing and cleaning of oils and fats such as machine oil adhering to these objects to be cleaned, silicone oil,
It is possible to satisfactorily remove and clean the release agent and grease. In particular, silicone grease, which is hardly soluble with other cleaning agents, can be easily removed.

Further, since no chlorofluorocarbon solvent is used, it is environmentally friendly, does not destroy the ozone layer, has excellent quick-drying properties, and does not cause dry spots on the surface of the article to be cleaned. Furthermore, a series of steps from washing to drying can be performed with the same liquid, and since there is no water washing step including the rinsing step, wastewater treatment is unnecessary. Furthermore, the liquid can be reused by the distiller, and the running cost can be reduced. Further, there is an advantage that materials such as plastic are unlikely to cause corrosion or solvent cracks.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a cleaning apparatus according to an embodiment of the present invention. This cleaning device is roughly divided into
It is composed of a degreasing / cleaning section A, a rinsing / cleaning section B, and a drying section C, and a cleaning object such as a metal part is stored in each of these sections A, B, and C, for example, in a cleaning basket or the like. It is configured to be sequentially conveyed in the state. Further, this cleaning apparatus is provided with a cleaning liquid distillation regeneration apparatus D.

The degreasing cleaning section A has a first cleaning tank 1 and a second cleaning tank 2, and a predetermined amount of cleaning liquid 3 is contained in each cleaning tank 1, 2. As the cleaning liquid 3, an azeotropic mixture of a low-molecular siloxane compound such as octamethylcyclotetrasiloxane (D4) and an aliphatic hydrocarbon solvent having 4 to 30 carbon atoms (for example, a volatile isoparaffin solvent) is used. To be done. In the cleaning liquid 3 of these cleaning tanks,
For example, by immersing the cleaning target housed in the cleaning basket and rocking the cleaning target up and down, dirt components derived from the machine oil or the like adhering to the cleaning target are removed.

An ultrasonic wave and jet generator 4 is arranged at the bottom of each of the first and second cleaning tanks 1 and 2 to apply a mechanical shock to the object to be cleaned and the cleaning liquid 3.
It is designed to improve the cleaning effect. Further, a pipe 6 having a filter 5 inserted therein is attached to each of the cleaning tanks 1 and 2, and a cleaning liquid 3 is circulated through the filter 5 by a pump P, and dirt components and corrosive substances are removed from the filter 5 during the circulation process. It is configured to be adsorbed and removed by.

The rinse cleaning section B has a rinse cleaning tank 7,
The rinsing bath 7 contains a predetermined amount of rinsing liquid 8. As the rinse cleaning liquid 8, the same composition as the cleaning liquid 3 is used.

Then, the cleaning liquid (and the rinse cleaning liquid) overflowing in each cleaning tank sequentially flows from the rinse cleaning tank 7 to the second cleaning tank 2 and then to the first cleaning tank 1. Further, the cleaning liquid 3 in the first cleaning tank 1 is introduced into the distillation / regeneration device D to separate and remove dirt components, and at the same time, the cleaning components are regenerated by distillation. The regenerated cleaning liquid is supplied to the rinse cleaning tank 7 by a pump (not shown) and reused. By using such a distillation / regeneration device D, the cleaning liquid can be repeatedly used, and the running cost can be further reduced.

The drying section C has a drying tank 9. The drying step can be performed by warm air drying, vacuum drying, reduced pressure drying, or reduced pressure steam / vacuum drying. With steam drying,
The drying tank 9 can contain a vapor cleaning (drying) agent having the same composition as the cleaning liquid described above. Since the cleaning liquid is an azeotropic composition and the vapor composition does not change, a good dry finish can be maintained.

Next, a concrete example of cleaning using such a cleaning apparatus will be described.

Example 1 First, a cleaning liquid was prepared in which cleaning, rinsing, and drying were performed in one liquid. The composition of each _component, C _{8 H 18} 2 wt% _{(hereinafter,.} Simply percent _shown), C _{9 H 20} is _{5%, C 1} 0 H
₂₂ is 8%, C ₁₁ H ₂₄ is 21%, C ₁₂ H ₂₆ is 56%
%, C ₁₃ H ₂₈ 7%, C ₁₄ H ₃₀ 1%, an isoparaffinic solvent which is a mixture of volatile isoparaffins, and octamethylcyclotetrasiloxane at 30:70.
The mixture was placed in a distillation flask at a weight ratio of, and repeatedly distilled under reduced pressure using a rectification column. By this distillation, 80 ℃ / 30m
An azeotropic fraction of mHg was obtained.

The obtained azeotropic component was analyzed by ¹ HNMR, and the actual blending ratio was quantified. As a result, a composition containing 72 parts by weight of isoparaffinic solvent and 28 parts by weight of octamethylcyclotetrasiloxane was obtained. The point belongs to the 2nd petroleum of 53 ℃.

Example 2 Example 1 except that the charge composition of isoparaffinic solvent and octamethylcyclotetrasiloxane was 65:35.
Distillation was performed in the same manner as above to obtain an azeotropic fraction at 83 ° C./29 mmHg. As a result of ¹ HNMR analysis of this fraction, it was found that the composition was 65 parts by weight of isoparaffinic solvent, 35 parts by weight of octamethylcyclotetrasiloxane, and had a flash point of 52 ° C. and belonged to a second petroleum product. .

Example 3 The composition of each component was such that C ₁₂ H ₂₆ was 20% and C ₁₃ H ₂₈ was
An isoparaffinic solvent, which is a mixture of volatile isoparaffins containing 30% C ₁₄ H ₃₀ 35% and C ₁₅ H ₃₂ 15%, and decamethylcyclopentasiloxane were placed in a distillation flask at a weight ratio of 83:17. Distillation was performed under reduced pressure.
By this distillation, an azeotropic fraction of 104 ° C./20 mmHg was obtained. Further, this fraction was repeatedly distilled under reduced pressure.

The components of the obtained fraction were analyzed by ¹ HNMR and the actual blending ratio was quantified. As a result, an azeotrope containing 90 parts by weight of isoparaffinic solvent and 10 parts by weight of decamethylcyclopentasiloxane was obtained. It was being done. The flash point was 78 ° C, and it belonged to the third petroleum.

[0039] Example 4 cycloparaffinic solvent 60% and a mixed solvent consisting of paraffinic solvent 40% _{(C 1} 1 _{H 22} is _{27%, C} 12 _{H 24} is
35%, C ₁₁ H ₂₄ 13%, C ₁₂ H ₂₆ 20%, C
₁₃ H ₂₈ consists of 5%. ) Was mixed with 30 parts by weight of decamethylcyclopentasiloxane at a ratio of 70 parts by weight, and the mixture was distilled under reduced pressure. As a result of distillation, a fraction of 104 ° C./20 mmHg was obtained. Further, this fraction was repeatedly subjected to vacuum distillation.

The components of the obtained fraction were analyzed by ¹ HNMR and the actual blending ratio was quantified. As a result, 67 parts by weight of cycloparaffinic solvent and 33 parts by weight of decamethylcyclopentasiloxane were obtained as an azeotrope. It was being done. The flash point was 70 ° C, and it belonged to the third petroleum.

Next, using the cleaning liquid having the azeotropic composition of Examples 1 to 4, the metal parts (bolts) to which the cutting oil adhered were cleaned by the above-mentioned cleaning device, and dried with warm air at 100 ° C. . Then, the time required for drying was determined.

For comparison, another cleaning agent having an equivalent flash point was used, cleaning was carried out in the same manner as in the example, followed by warm air drying, and the time required for drying was determined. In Comparative Example 1, an n-paraffinic solvent (having a composition of C ₁₀ H ₂₂ 99% and C ₁₁ H ₂₄ 1%), Comparative Example 2 in the isoparaffinic solvent used in Example 1, and Comparative Example 3 in Isoparaffinic solvent used in Example 3, Comparative Example 4
The cycloparaffinic solvent used in Example 4 and the glycoetheric solvent (3-methyl-3-methoxybutanol) in Comparative Example 5 were used for cleaning.

As a result, Comparative Example 1 having an equivalent flash point
As shown in Table 1, as compared with the case where the cleaning agents of ~ 5 were used, it was possible to dry in the shortest half time. In addition, when the surface of the dried component was visually observed, no stain was observed.

[0044]

[Table 1]

Furthermore, as a result of the ESCA analysis of the surface of the part after cleaning, a peak derived from silicone (100160 eV Si
Atomic absorption) was not detected. Therefore, it was confirmed that silicone, which is a component of the cleaning liquid, does not remain on the dried parts.

Next, the detergency for silicone grease, which is considered to be insoluble in other detergents, was examined. That is, a metal copper plate coated with about 2 g of silicone grease was prepared. Then, a cleaning liquid having the same composition as the cleaning liquid having the azeotropic composition prepared in the above Example was used, and the cleaning liquid was then dried. Cleaning conditions are from flash point
Sonicate at 10 ℃ lower temperature for 15 minutes, then 100 ℃
It was dried with warm air for 15 minutes.

The residual rate of the silicone grease on the surface of the sample washed and dried in this manner was measured gravimetrically to find the residual rate. As shown in Table 2, the residual rate of the silicone grease before cleaning was 100, and the residual rate was 0. Became. For comparison, the cleaning agents of Comparative Example 1, Comparative Example 2 and Comparative Example 4, the halogen-based solvent (methylene chloride) as Comparative Example 6 and the fluorine-based solvent (hydrofluoroether) as Comparative Example 7 were used, respectively. The results of the same washing,
Shown in the same table. In Comparative Example 6, ultrasonic cleaning was performed at 30 ° C. for 15 minutes using a halogen-based solvent, and in Comparative Example 7,
Ultrasonic cleaning was performed at 40 ° C for 15 minutes using a fluorine-based solvent.

[0048]

[Table 2]

[0049]

As described above, according to the present invention,
It can satisfactorily perform degreasing and cleaning of oils and fats such as machine oil adhering to objects to be cleaned such as metal parts, and removal and cleaning of silicone oil, silicone grease, etc. Does not leave a spot. Also, since no CFC-based solvent is used, there is no concern about environmental damage or environmental pollution. Further, since it is a non-aqueous one-liquid cleaning agent, a series of steps from cleaning to drying can be performed with the same liquid, and since there is no water washing step including a rinsing step, wastewater treatment is unnecessary.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a cleaning apparatus according to an embodiment of the present invention.

[Explanation of symbols]

A: Degreasing cleaning section B: Rinse cleaning section C: Drying section D: Distillation regeneration unit 1: First cleaning tank, Second cleaning tank, 3 ...
… Cleaning fluid, 4 ……… Ultrasonic wave and jet generator, 5 ……
… Filters, 7 ……… Rinsing tank, 9 ……… Drying tank

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/304 647 H01L 21/304 647A F term (reference) 3B201 AA46 AB38 AB45 BB04 BB05 BB95 CB15 CC01 CC12 CC15 CD22 4H003 DA09 DA14 DA15 DB02 DC04 EB25 ED04 ED32 FA01 FA03 FA21 FA46 4K053 PA02 PA17 QA06 RA32 SA06 ZA01

Claims (11)

[Claims] 1. A cleaning agent, which is a mixture of an azeotropic composition or a pseudo-azeotropic composition comprising a low-molecular siloxane compound and an aliphatic hydrocarbon solvent having 4 to 30 carbon atoms. 2. The cleaning agent according to claim 1, wherein the aliphatic hydrocarbon solvent is an isoparaffin solvent. 3. The cleaning agent according to claim 2, wherein the isoparaffin-based solvent consists essentially of volatile isoparaffin. 4. A cleaning agent, which is a mixture of an azeotropic composition or a pseudo-azeotropic composition containing a low molecular siloxane compound and an alicyclic hydrocarbon solvent having 4 to 30 carbon atoms. 5. The cleaning agent according to claim 4, wherein the alicyclic hydrocarbon-based solvent is a cycloparaffinic solvent. 6. The cleaning agent according to claim 5, wherein the cycloparaffinic solvent consists essentially of volatile cycloparaffins. 7. The low-molecular-weight siloxane compound has the general formula: (In the formula, R is the same or different and is substituted or unsubstituted 1
A straight-chain polydiorganosiloxane represented by a divalent hydrocarbon group, l represents an integer of 0 to 5, and a general formula: (In the formula, R is the same or different and is substituted or unsubstituted 1
7. A low molecular weight polyorganosiloxane selected from cyclic polydiorganosiloxanes represented by a valent hydrocarbon group, m is an integer of 3 to 7), The cleaning agent according to item 1. 8. The cleaning agent according to claim 7, wherein the low molecular weight polyorganosiloxane is octamethylcyclotetrasiloxane or decamethylcyclopentasilosaquin. 9. A series of steps from washing to drying is carried out in one liquid by using a mixture of an azeotropic composition or a pseudo-azeotropic composition comprising a low molecular weight siloxane compound and an isoparaffinic solvent having 4 to 30 carbon atoms. A cleaning method characterized by the above. 10. A series of steps from washing to drying is performed by one liquid using a mixture of an azeotropic composition or a pseudo-azeotropic composition containing a low molecular weight siloxane compound and a cycloparaffinic solvent having 4 to 30 carbon atoms. A cleaning method characterized by performing. 11. The low-molecular-weight siloxane compound has the general formula: embedded image (In the formula, R is the same or different and is substituted or unsubstituted 1
A straight-chain polydiorganosiloxane represented by a divalent hydrocarbon group, l represents an integer of 0 to 5, and a general formula: (In the formula, R is the same or different and is substituted or unsubstituted 1
11. A cleaning method according to claim 10, which is at least one low molecular weight polyorganosiloxane selected from cyclic polydiorganosiloxane represented by a valent hydrocarbon group, m is an integer of 3 to 7). .