KR970002044B1 - Detergent and drying compositions and their method - Google Patents

Abstract

None.

Description

Cleaning and drying compositions, and cleaning and drying methods

1 is a flowchart of cleaning and drying in Example 14 of the present invention.

2 is a sectional view of a playback apparatus used in a fourteenth embodiment;

3 is a perspective view of the separation tank.

4 is a sectional view of a separate playback device used in a fourteenth embodiment;

5 is a sectional view of the apparatus used in Example 15. FIG.

* Explanation of symbols for main parts of the drawings

11: washing tank 12: inner tank

13: outer tank 14: ultrasonic oscillator

15 non-aqueous solvent 16: recovery pipe

17 separation tank 18 non-aqueous solvent discharge pipe

19: separation liquid 20: discharge hole

21: regeneration liquid circulation pipe 22: pump

23 filter 24 top cover

25 float switch 26 supply tank

27: supply pipe 28: valve

29: separation liquid supply pipe 30: separation liquid discharge pipe

31, 32: valve 51: drying tank

52: separation tank 53: discharge valve

57: supply tank 58: supply valve

59: discharge valve 60: outlet tank

61, 62: partition plate 71: separation plate

72: liquid inlet 73, 74: separator

75: liquid outlet 76: liquid level sensor

77 pure water 78 non-aqueous solvent

79 filter 80 pump

83, 84: liquid level sensor 100: washing and drying means

110: washing and drying 111: cover

112: receiving member 113: heat insulation

120: separation tank 121: tank

122: circulation path 123: vacuum pump

124: discharge valve 125: filter

126 pump 127 condenser

129: inlet pipe 130: steam generation

131: heater 132: heating coil

133: level gauge 134: hot water tank

135: hot water pump 136: auto trap

137: liquid level gauge 151, 152: pipeline

153, 154 exhaust valve 155 condenser

156: pipeline 157: exhaust valve

158: condenser 160: pipeline

161: liquid feed pump 162: filter

163: automatic valve 164: non-return valve

170: pipeline 171, 172: air valve

173: cooking valve 200: recovery means

300: steam generating means 400: object to be cleaned

The present invention provides a method for cleaning degreased, precisely cleaned or easy hand-washed and / or cleaned objects such as optical or molded parts of metal or plastic, metal parts, ceramic parts, electronic parts, etc. The present invention relates to a cleaning and drying composition used for drying, and a cleaning and drying method.

In particular, the present invention relates to a cleaning and drying composition that does not use prone, which has been used worldwide in recent years, and a cleaning and drying method.

In general, industrial parts such as optical parts, molded parts, and electronic parts are subjected to precision drying for degreasing, followed by finishing drying.

Moreover, in the optical parts and molded parts, it is necessary to remove fingerprints and dust after manufacturing, and therefore, simple washing by hand washing with a cotton paper wetted with a solvent, etc. is performed.

Simple cleaning by this hand washing is also performed in the mold.

1.1.2-Trichloro-1.2.2-trifluoroethane (Fron 113) is conventionally used for the above various washing | cleaning and drying after washing | cleaning.

This Prolon 113 is nonflammable, has low toxicity to living organisms, has a fast drying speed, and does not erode polymer materials such as plastic and rubber, and has a selective solubility to dissolve fats and oils.

However, overhaloethanes such as Fron 113 are chemically stable, so they have a long lifetime in the troposphere and diffuse to reach the stratosphere, where halogen radicals generated by decomposition with sunlight cause a chain reaction with ozone and destroy the ozone layer. In this regard, the regulation of their usage is required.

In order to reduce the amount of Prolon 113 used for the purpose of protecting the ozone layer, cleaning and drying using a number of mixed solvents or azeotropic compositions have been developed.

For example, Japanese Unexamined Patent Publication No. 318094 discloses a solvent obtained by mixing pron 113, isopropyl alcohol, and methyl ethyl ketone, and Japanese Unexamined Patent Publication No. 289693 discloses dichlorotetrafluoro. Azeotropic compositions of propane (pron 234) and aliphatic lower alcohols such as ethanol are described.

In the drying, the final drying is also performed using the vapor of isopropyl alcohol (IPA).

However, since the mixture described in JP-A-318094 discloses that it is necessary to contain pron 113, the amount of the pron 113 cannot be reduced to some extent.

On the other hand, in the azeotropic composition described in Unexamined Patent Publication No. 289693, Pron 234 is used.

The prolon 234 is relatively less destructive than the prolon 113, but cannot destroy the ozone layer completely.

On the other hand, drying using vapor of IPA may cause moisture absorption and mixing of water slowly during repeated cleaning due to the high hygroscopicity of IPA, which may cause staining under the influence of water, etc. There is a risk, and there is a problem such as deterioration of plastics and the like, which is not practical.

The present invention has been made in consideration of such circumstances, and can be used in a state in which it is not affected by water without using a proton that destroys the ozone layer, and has a low risk of flammability. It is an object of the present invention to provide a cleaning and drying composition which is free of charge and a method of cleaning and drying.

The present invention is used for cleaning, hand washing or finishing drying of objects to be cleaned such as optical parts, molded parts made of glass, plastic, metal parts, ceramic parts, and electronic parts.

The cleaning and drying composition of the present invention contains hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetri-siloxane as active ingredients, which are positioned as low molecular weight siloxanes.

In general, the volatility of cidolic acid is proportional to its viscosity or molecular weight, but an active ingredient of siloxane having a viscosity of about 5 CSt (25 ° C.) has a volatility and the hexamethyldissiloxane, octamethyltrisiloxane, and octamethyl of the present invention. Cyclotetrasiloxanes have a particularly high volatility because they all have a viscosity of 5 CSt or less.

In addition, this low viscosity (low molecular weight) siloxane has its own and solventic behavior, and itself degreasing fingerprints and sebum.

In addition, it is less toxic to the living body and chemically stable and hardly affects objects such as plastics, rubber, metals and porcelain.

And since it does not contain halogen, such as chlorine, there is no bad influence to an ozone layer.

Siloxane having this property has a good drying speed and can be used for simple hand washing or finishing drying, such as finishing cleaning of optical parts or molded parts, such as a vitreous lens, plastic, and mold cleaning.

Low molecular siroxane has a straight chain and a cyclic phase and is represented by Chemical Formulas 1 and 2.

In the present invention, n = 0 hexamethyldisiloxane, n = 1 octamethyltrisiloxane, and m = 4 octamethylcyclotetrasiloxane are selected.

As a hand washing finish liquid, a fine washing liquid, and the drying solution after washing which are the uses of this invention, you may mix 2 or more types of low molecular siloxanes mentioned above, and may add a stabilizer, a solvent, etc.

As stabilizers, acetylene alcohols such as aliphatic nitro compounds such as nitromethane, nitroethane, nitropropane, 3-methyl-1-butyn-3-ol and 3-methyl-1-penten-3-ol, glycidol and methylglycol Epoxides such as cydyl ether, allyl glycidyl ether, phenylglycidyl ether, 1.2-butylene oxide, cyclohexene oxide, epichlorohydrin, dimethoxymethane, 1.2-dimethoxyethane, 1.4-dioxene Ethers such as, 1.3.5-trioxene, unsaturated hydrocarbons such as hexene, heptane, octene, 2.4.4-trimethyl-1-pentene, pentadiene, octadiene, cyclohexene, cyclopentene, aryl alcohol, 1- Olefinic alcohols, such as butene-3-ol and 3-methyl-1- butene-3-ol, acrylic esters, such as methyl acrylate, ethyl acrylate, and butyl acrylate, can be used individually or in combination of 2 or more types, respectively.

In addition, these compounds and phenols such as phenol, trimethyl phenol, cyclohexyl phenol, thymol, 2.6-di-t-butyl-4-methyl phenol, butyl hydroxyanisole and isoigenol, hexylamine, pentylamine and di Propylamine, diisopropylamine, diisobutylamine, triethylamine, tributylamine, pyridine, N-methylmorpholine, cyclohexylamine, 2.2.6.6-tetramethyl pyriridine, N, N'-diaryl Amines such as -P-phenylenediamine, triazoles such as benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and chlorobenzotriazole may be used in combination.

By adding 0.1-10 wt% of these stabilizers, the quality can be stabilized without deteriorating performance.

As the solvent, hydrocarbons such as pentane, isopentane, hexane, isohexane, heptane, nitroalkanes such as nitromethane, nitroethane, nitropropane, diethylamine, triethylamine, isopropylamine, butylamine, iso Amines such as butylamine, alcohols such as methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, i-butanol, ethers such as methyl cellosolve, tetrahydrofuran, 1.4-dioxane, One kind or two or more kinds selected from ketones such as acetone, methyl ethyl ketone and methyl butyl ketone, and esters such as ethyl acetate, propyl acetate and butyl acetate can be used.

1-80 wt% of these solvents can be added to improve the dissolving power.

As a low molecular siloxane of this invention, when using hexamethyl disiloxane, ethanol, methanol, 2-propanol can be mixed and used.

In the mixture of hexamethyldisiloxane and ethanol, methanol or 2-propanol, it is preferable that this mixture is an azeotropic composition (azeotropic composition) or a composition close to azeotropy (azeotropic composition).

Hexamethyldisiloxane is composed of the chemical formula (CH ₃ ) ₃ SiOSi (CH ₃ ) ₃ , which has a viscosity of 0.65 CSt (25 ° C.).

The azeotropic composition which is a preferable state of the present invention cannot be obtained by simply mixing two or more components, but has azeotropic point, that is, azeotropic composition.

Such azeotropic compositions have excellent characteristics such as constant boiling point different from those of each component and when the boiling point is low, the volatilization rate is increased, and the ratio of the composition or the effluent does not change at all as a result of evaporation.

The composition having such an azeotropic state is 35.7-36.7 wt% of ethanol relative to 64.3-63.3 wt% of hexamethyldisisiloxane at normal pressure in the case of ethanol, and has a boiling point of 71.4 ° C. in this range.

On the other hand, in the case of methanol, methanol is 40.7-41.1 wt% with respect to 58.9-59.3 wt% of hexamethyldissiloxane, and the composition has a boiling point of 58.7 占 폚 lower than the boiling point of each component, resulting in improved volatility and evaporation. Since the composition and the liquid composition are almost unchanged, there is almost no change in composition due to evaporation and a stable liquid composition.

In addition, the composition having azeotropy in the system consisting of 2-propanol and hexamethyldissiloxane was 45.5-45.9 wt% with respect to 54.1-54.5 wt% of hexamethyldissiloxane, and its boiling point was higher than that of each component. Since the low volatility is 76.4 ° C., the volatility is improved and the composition and the liquid composition are almost unchanged.

On the other hand, hexamethyldisiloxane 30-95wt%, methanol 5-70wt% range, hexamethyldisiloxane 35-99wt% ethanol 1-65wt% range, hexamethyldisiloxane 25-95wt%, 2-propanol 5-75wt Even in the range of%, the boiling point on the outer surface also decreases from each component (for example, the boiling point at 25 wt% of hexamethyldisiloxane and 75 wt% of 2-propanol is 77.7 ° C), and there is no large compositional change due to evaporation. It is practical as a liquid, a precision cleaning liquid, and a drying liquid.

Hexamethyldisisiloxane, which is one component in the above mixture, is less toxic to living organisms, chemically stable, and hardly affects plastics, rubber, metals, glass, and the like.

It does not contain halogens such as chlorine and therefore does not affect the ozone layer.

Other components, ethanol, methanol or 2-propanol, have a great degreasing power and slow down the contamination rate of oils and fats.

In particular, ethanol, as it is known, has the characteristics of low toxicity to the living body and high stability.

Therefore, the azeotropic or azeotropic composition composed of such components can be suitably applied as a hand washing finish liquid for industrial parts, as a precision cleaning liquid or as a drying liquid after washing, and when used as a solvent or a drying liquid, liquid management at the time of use is easy. It can be easily recovered, reused and steam cleaned.

In such a mixture of hexamethyldisiloxane and ethanol, methanol or 2-propanol, it is possible to add the stabilizer described above in the above-described blending ratio.

In this case, a compound having a great effect of stabilizing an azeotrope composition and an azeotropic composition and of having a property of forming an azeotrope as a result of co-flowing by distillation is preferred.

The first method in the washing and drying method of the present invention uses a low molecular weight siloxane that has a content of dodecamethylpentasiloxane less than 0.01% by weight and substantially removes a compound having a lower volatility than dodecamethylpentasiloxane. It is.

Dodecamethylpentasiloxane and its less volatile compounds are significantly less volatile, and when they are present in trace amounts, stains or residues occur after drying, resulting in deterioration of cleaning and drying quality.

In this case, the washing includes various washing such as degreasing washing, fine washing, hand washing and the like.

On the other hand, drying is a final step of cleaning the object to be cleaned, and before this final step, degreasing of the object to be cleaned using a surfactant, water washing using pure water, and alcohol replacement (water replacement process) after water washing are performed. Various washing processes conventionally performed are performed, and drying using the low molecular weight siloxane of this invention as a finishing drying liquid is advanced after that.

In addition, the present invention also includes supplying the above-mentioned low molecular weight siloxane in the form of a vapor under reduced pressure to wash and dry the object to be cleaned.

Here, the substantially removed state means that the level is not detected even by using general separation analysis such as GC (gas chromatography) or LC (liquid chromatography).

In addition, as a measure of the degree of volatility, the vapor pressure is aimed at the vapor pressure, and other factors are considered in consideration of latent heat of evaporation.

As the low molecular siloxane in the first method, hexamethyldisiloxane, octamethyltrisiloxane or octamenylcyclotetrasiloxane are preferable, and these can also be used in a mixture of these low molecular siloxanes.

The reason for using low molecular weight siloxane is because it is not toxic to the living body, is chemically stable, has little effect on plastic, rubber, metal glass, etc., and does not contain halogen such as chlorine, and thus high safety without affecting ozone layer.

The first method is to immerse and raise the above-mentioned finishing drying liquid after the washing step or the water replacement step, and thereafter drying by normal temperature standing, blowing or reduced pressure steam drying.

These drying methods can be used individually or in combination.

When the low molecular weight siloxane is used in combination, a stabilizer or a solvent can be added. However, the stabilizer and the solvent have a property of stabilizing the dry liquid used, and more preferably, distillation It is preferable to form azeotropes.

The low molecular weight siloxane used in the first method removes dodecamethylpentasiloxane, etc. by adsorption of distillation, rectification, and / or activated carbon.

This composition is less than 0.01% by weight of dodecamethylpentasiloxane, and furthermore, except that it has a lower volatility than dodecamethylpentasiloxane, there is no stain or residue after drying such as blowing air or reduced pressure steam drying. .

Table 1 shows the result of confirming the effect of the trace amount of volatile bad components to the finish state by the following experiment.

This experiment was performed by adding 0.001% by weight of dodecamethylpentasiloxane to octamethyltrisiloxane and octamethylcyclotetrasiloxane with purity of 99.999% or more in gas chromatography obtained using a 30-stage or higher distillation apparatus. After immersing the clean slide glass in the liquid, drying it and blowing air, it was carried out by an aerobic test in which the stains and residues were judged from a binocular stereo microscope and a cloudy state at exhalation.

Similarly, tetradecamethylnuxasiloxane, which is a molecular weight larger than dodecamethylpentasiloxane and less volatile, was added in 0.001% by weight to perform the same experiment.

In this evaluation, stains and residues were not found in either of the binocular stereoscopic observation and aerobic tests, and in Table 1, the stains and residues were confirmed as x by either observation.

However, Table 1 is taken from the above experiment.

From these results, it is understood that staining and residues are generated when more than 0.01% by weight of dodecamethylpentasiloxane is contained or even a small amount of tetradecamethylnuxasiloxane, which is less volatile than dodecamethylpentasiloxane, is contained. Can be.

A component ... Dodecamethylpentasiloxane

B ingredient ... ..Tetradecamethylhexasiloxane

The second method in the washing and drying method of the present invention is to use a low-molecular siroxane as a rinse liquid in the final step of washing the object to be cleaned, and to wash the steam after immersing and removing the substance to be washed in the rinse liquid. .

In this second method, as a rinse liquid, polymers are more straight-chain siloxanes, dodecamethylcyclohexane siloxanes, and dodecamethylcyclohexane siloxanes of polymers than dodecamethylpentasiloxane and dodecamethylpentasiloxane. Cyclic siloxanes and low molecular weight siloxanes substantially free of organic compounds having a molecular weight of at least equal to these are used.

These substantially free state is a level which is not detected even if using general separation analysis, such as GC and LC like 1st method.

Especially in a 2nd method, the value of about 100 ppm (0.01 weight%) or less is meant as these content rates.

As the low molecular siloxane in the second method, a single molecule or a mixture of low molecular siloxanes such as straight chain siloxane and cyclic siloxane can be used, and among these, low molecular dimethylsiloxane is preferable.

Here, hexamethyldisiloxane, octamethyltrisiloxane, or octamethylcyclotetrasiloxane are preferable and practical in consideration of the volatility and the risk of ignition as the low molecular weight dimethylsiloxane.

These low molecular weight dimethylsiloxanes can also be used by two or more types of mixed systems.

In the steam washing performed after such rinsing, a perfluorocarbon compound is used as the steam washing liquid.

Perfluorocarbon compounds are colorless, transparent, odorless, and inert, and have excellent characteristics such as low turbidity, incombustibility, high stability, and zero ozone decay coefficient to rubber-plastics.

This perfluorocarbon compound is selected in consideration of the rinse liquid used in the drying of the steam cleaning process, the usability, the thermal characteristics mainly due to boiling point, the heat of evaporation, and the consumption.

In consideration of these characteristics, the boiling point is preferably 100 ° C. or lower for a to-be-cleaned material such as plastic, and the boiling point is 150 ° C. or less from the viewpoint of workability of a post-process for a to-be-cleaned material such as a metal or an inorganic material. Is preferred.

As the perfluorocarbon compound having a boiling point of 150 ° C. or lower, one or a mixture of two or more of basic chemical structural formulas such as CF (boiling point 56 ° C.), CF (boiling point 80 ° C.), CF (boiling point 102 ° C.), etc. may be used. Can be.

Also in the second method, a stabilizer and a solvent can be added to the low molecular weight siloxane used as the rinse liquid, but it is preferable that the same flows out or forms an azeotrope as in the first method as the stabilizer or the solvent.

As for the low molecular weight siloxane used for the rinse of the second method, dodecamethylpentasiloxane is removed by adsorption means such as distillation, rectification, and / or activated carbon.

In this way, in the steam cleaning step, the effect of infiltrating and replacing the interface with the rinse liquid adhering to the surface of the object to be cleaned, and the effect of the rinse liquid and steam being replaced by substitution, occurs.

However, when the rinse liquid contains perfluorocarbon vapor and an egg phase compound, the substitution compatible with the rinse liquid becomes difficult, and residues such as stains are generated.

Generally, when the compatibility of perfluorocarbon and siloxane is the same in basic structure, the compatibility decreases as the polymer becomes inversely proportional to the molecular weight.

The low molecular weight siloxane used in the rinsing step of the second method substantially removes the egg-like compound as described above, and confirms the usability of the low molecular weight siloxane as a rinse solution and the perfluorocarbon as a steam cleaning solution by the following experiment. did.

Chloromethylsiloxanes, decamethyltetrasiloxanes, detradecamethylhexasiloxanes and straight chain siloxanes in 100 ml of perfluorocarbons of the basic chemical structures CF (boiling point 80 ° C.) and CF (boiling point 102 ° C.), respectively, and Dodecamethylpentasiloxane and octamethylcyclotrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexanesiloxane as cyclic siloxanes are each added in a volume ratio of 50%, stirred and heated.

Then check the status when reboiling.

The results are shown in Table 2.

In Table 2, x is used to separate siloxane and pifluorocarbon, △ is mixed with siloxane and perfluorocarbon in turbidity, and ○ is used in transparent state. Show what you are doing.

As for the low molecular weight siloxane used for the above rinse liquid, more than the straight chain siloxane, dodecamethylcyclohexasiloxane, and dodecamethylcyclohexasiloxane of a polymer than dodecamethyl pentasiloxane and dodecamethyl pentasiloxane. It is preferable that the cyclic siloxane of the polymer and the organic compound having a molecular weight equal to or higher than these are substantially not contained.

Further, by immersion and drying in the rinse liquid, steam cleaning using a perfluorocarbon compound is performed, whereby good washing and finishing drying can be performed.

However, drying with IPA steam is performed by first washing the solvent to be washed, then washing with water-based surfactant, washing with constant water, washing with pure water, and then washing with IPA to remove water, followed by final drying process. In this order, IPA is vaporized and released to dry the object to be cleaned.

However, since IPA vapors are flammable and explosive and harmful to humans, they require handling care and have large recovery facilities.

On the other hand, the inventors of the present invention found that the hydrophilic solvent such as IPA attached to the object to be cleaned is replaced with a low molecular weight siloxane to allow drying and no drying by IPA vapor is required.

Examples of the low molecular siloxane in this case include hexamethyldisiloxane, octamethylcyclotetrasiloxane, and octamethyltrisiloxane.

However, in the washing | cleaning which uses such a low molecular weight siloxane for drying of a final process, a stain and a stain arise in the to-be-cleaned object as washing | cleaning is repeated.

This is because the low molecular weight siloxane dissolves a hydrophilic solvent such as IPA and removes the hydrophilic solvent. As a result of the increase in the number of washings, the concentration of the hydrophilic solvent in the low molecular weight siloxane increases, resulting in the moisture accompanying the hydrophilic solvent. Moisture content in the siloxane increases, causing stains and stains.

In the present invention, a non-aqueous solvent such as low molecular weight siloxane mixed with a hydrophilic solvent is brought into contact with a separation solution such as water to separate the hydrophilic solvent from the non-aqueous solvent to regenerate the non-aqueous solvent.

In this way, the content of the hydrophilic solvent in non-aqueous solvents, such as low molecular weight siloxane, used for drying is kept low, and circulation use is possible in the state which kept drying power.

As a non-aqueous solvent used for this invention, it is good to have volatility under normal temperature, and to have usability with a hydrophilic solvent, and the low molecular weight siloxane of this invention fully satisfy | fills these conditions.

In addition, the separation liquid is insoluble in non-aqueous solvents, and furthermore, its usability with hydrophilic solvents is better than that of non-aqueous solvents. When the low molecular weight siloxane of the present invention is used for non-aqueous solvents, water or pure water can be selected.

A hydrophilic solvent is used for water removal of a to-be-cleaned object, and alcohol, such as IPA, is used a lot as this hydrophilic solvent.

By the way, hydrophilic solvents such as alcohol have high hygroscopicity, and when water is immersed and dried in a hygroscopic state, residues are generated on the surface of the object to be cleaned.

This removes the water and dries it.

Drying is carried out by dipping in a non-aqueous solvent.

In this drying, hydrophilic solvents, such as alcohol, enter the non-aqueous solvent by to-be-cleaned objects, such as a glass lens and an electric substrate.

That is, the concentration of the hydrophilic solvent in the non-aqueous solvent increases as the hydrophilic solvent such as alcohol attached to the object to be washed dissolves in the non-aqueous solvent and the washing is repeated.

Here, non-aqueous solvents are prepared by mixing a separation solution such as water having an excellent compatibility with a hydrophilic solvent such as alcohol, having a specific gravity greater than that of the non-aqueous solvent and having no compatibility with the non-aqueous solvent (insoluble). Hydrophilic solvents, such as alcohol dissolved in them, are attracted to the separation solution having more affinity than non-aqueous solvents.

As a result, it decompose | disassembles into a two-liquid layer, and the separation liquid and attracted hydrophilic solvent which are heavy compared with a non-aqueous solvent in the lower part have only a non-aqueous solvent in the upper part.

In this way, the hydrophilic solvent can be decomposed from the non-aqueous solvent to regenerate the non-aqueous solvent.

In addition, the non-aqueous solvent of the present invention is required to be compatible with hydrophilic compounds such as alcohol, and to have high dryness of the object to be cleaned. Hexamethyldisisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane are required. Satisfies these characteristics.

High compatibility with the hydrophilic solvent is required to clean the hydrophilic solvent adhering to the object to be cleaned.

Another characteristic required for non-aqueous solvents, high dryness, is achieved with low molecular weight.

In this respect, the molecular weight of the silicone compound is preferably 1000 or less.

In general, the silicone compound has a correlation between the molecular weight and the viscosity, and if the molecular weight is low, low viscosity and high dryness are obtained as the low viscosity silicone compound.

In this case, the viscosity is preferably 5CSt (20 占 폚) or less, and hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane are most preferred in consideration of the drying rate and the compatibility of alcohol.

Above that, the drying property is remarkably slow.

Example 1

Commercially available hexamethyldissiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.) having a viscosity of 0.65 CSt (25 ° C.) was purified to remove impurities.

Commercially available hexamethyldisisiloxane contains 97.5% purity in gas chromatograph analysis and contains siloxanes and organic compounds that are less volatile than dodecamethylpentasiloxane as impurities.

This is because these impurities may remain as residues on the symmetrical objects of the finish cleaning, and a treatment for removing volatile components than dodecamethylpentasiloxane is required.

Removal of this impurity is carried out by appropriate means of distillation, rectification, and adsorbent. Thus, purity became 98.0%.

Table 3 shows the test results of hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane prepared in this way. In the table, n and m represent n and m of Formulas 1 and 2 described above. Indicates at 25 ° C.

In the table, a 1: 1 mixture of a pron-ethanol azeotropic liquid and ether-ethanol is used as a comparative example.

Hereinafter, each test method and evaluation standard in a present Example are demonstrated.

(1) Turbidity to various materials

Plate made of aluminum, stainless steel (SUS 304), copper, glass, PP (polypropylene), PC (polycarbonate), PMMA (polymethyl methacrylate), ABS (acrylonitrile-butadiene-styrene) Was immersed in each of the solutions shown in Table 3, and the weight change and visual inspection after 48 hours were performed.

Among them, the visual inspection was performed at 50 times magnification, and the presence of cracks was observed using a binocular stereo microscope.

The results are shown in the tackiness column of Table 3, but in this column ○ indicates that the weight change is less than 0.1% for all materials, and there is no change in appearance, × is the weight change for all materials with 0.1% or more. Indicates that there was a change in appearance.

In addition, in the ether-ethanol liquid mixture of the comparative example, a crack generate | occur | produced in the board material which consists of PC, PMMA, and ABS.

(2) drying speed

After putting each liquid of Table 3 into the beaker and immersing a glass plate, the glass plate was raised vertically and the dry state was observed. As a glass plate, it was the slide glass used for a microscope, and the single side | surface was roughened and used in the dim shape.

The results are shown in the drying rate column of Table 3, where ○ indicates that drying is completed within 60 seconds, and × indicates that 61 seconds or more is required for drying.

(3) degreasing power

A fingerprint (sebum) having an area of 1 cm 2 was attached on the glass plate, and 3 cc of each solution in Table 3 was wetted with a surface table (5 cm x 5 cm), and the glass plate was wiped with a constant force to test the degreasing force.

At this time, the number of times of wiping when fingerprint marks disappeared was examined.

The results are shown in the degreasing force column of Table 3, where ○ indicates that the number of times until the equity disappears is 5 or more, and × indicates that the number of times until the fingerprint disappears is 6 or more.

(4) stability

In the large environment column of Table 3, environmental destruction was described.

(Circle) shows that there is no environmental destruction, and x shows that there is environmental destruction.

In the human body column of Table 3, the hazards to the human body are described.

(Circle) shows that there is no physiological activity, (triangle | delta) shows that physiological activity is weak, and x shows that physiological activity is strong.

Subsequently, each liquid in the Examples column of Table 3 was placed in a hand wrap and handwashed with each plastic plate of PMMA, glass garden PC, PP, and ABS. However, all the plastic plates were satisfactory without any haze.

In addition, in the present embodiment, fingerprints attached to each of the plastic plates described above were hand-washed using hexamethyldisiroxane having a purity of 98%, so that the fingerprints could be removed from all the plastic plates.

In addition, the same washing | cleaning effect was acquired also in octamethyl trisiloxane and octamethyl cyclo tetrasiloxane.

Example 2

Commercially available hexamethyldissiloxane was purified by distillation, rectification, and adsorbent to remove hydrocarbon-crab compounds, siloxanes having a viscosity of 1 cSt (25 ° C.) or more, more difficult to volatilize than hexamethyldissiloxane, which was incorporated as impurities.

This is because these impurities may become residues on the object to be cleaned.

The purity of hexamethyldisisiloxane obtained by this purification was analyzed by gas chromatography, and the result was 99.0% or more.

In addition, the viscosity of this hexamethyldisisiloxane was 0.65 cSt (25 degreeC).

Thus purified hexamethyldisiloxane and 100 g of ethanol having a purity of 99.5% or more were put in a distillation flask, respectively, to 200 g, and rectified under normal pressure using a 30-step theoretical column.

By this rectification, azeotropic rectification was obtained at 71.4 degreeC.

The oil was analyzed by gas chromatography, and the composition was 64.3-63.3% for hexamethyldissiloxane and 35.7-36.7% for ethanol.

In addition, a stabilizer can be added in this Example.

As a stabilizer, for example, aliphatic nitro compounds such as nitromethane, nitroethane, nitrobutane, acetylene alcohols such as 3-methyl-1-butyl-3-ol, 3-methyl-1-pentone-3-ol, and glycidol Epoxides such as methylglycidyl ether, acrylglycidyl ether, phenylglycidyl ether, 1.2-butylene oxide, cyclohexene oxide, epichlorohydrin, dimethoxymethane, 1.2-dimethoxyethane, 1.4-di Ethers such as oxene and 1.3.5-trioxene, unsaturated hydrocarbons such as hexene, heptane, octene, 2.4.4-trimethyl-1-pentene, pentariene, octadiene and cyclohexene cyclopentene, aryl alcohol, 1 Olefinic alcohols, such as -butene-3-ol and 3-methyl-1- butene-3-ol-, acrylic esters, such as methyl acrylate and butyl acrylate, can be used individually or in combination of 2 or more types.

In addition, these compounds and phenols such as phenol, trimethyl phenol, cyclohexyl phenol, thymol, 2.6-to-t-butyl-4-methyl phenol, butylhydroxyanisole and iso igenol, hexylamine, pentylamine and di Propylamine, diisopropylamine, diisobutylamine, triethylamine, tributylamine, pyridine, N-methylmorpholine, cyclohexineamine, 2.2.6.6-tetramethylpyrrridine, N, N'-diaryl You may use together with amines, such as -P-phenylenediamine, triazoles, such as benzotriazole and 2- (2'-hydroxy-5'-methyl- phenyl) benzotriazole, and chloro benzotriazole.

By adding such a stabilizer, deterioration of performance or the like can be confirmed, and more stable characteristics can be given.

Example 3

200 g of the mixture in which the hexamethylsiloxane was purified in Example 2 was in the range of 99.0-10.0% and ethanol was in the range of 1.0-90.0 wt%, and the compounding ratio was changed every 1 wt%, and the boiling point of these mixtures was measured.

The results are shown in Table 4 in the distillation mode and observed boiling point fields.

In Table 4, the mixture having a blend ratio of 35.0 wt% or more of hexamethyldisisiloxane has an increase in boiling point of less than 1.0 DEG C with respect to the azeotropic point (71.4 DEG C) of the azeotrope of Example 2, as in Example 2 It consists of an azeotropic composition which can be implemented, and it is called the manufacture of Example 3 below.

Moreover, also in this Example, the stabilizer shown in Example 2 can be added.

Example 4

200 g of a mixture of 99.0-10.0 wt% of hexamethyldisiloxane having been purified in Example 2 and 1.0-990.0 wt% of ethanol, the compounding ratio of which was changed every 1 wt%, were prepared.

Each of these mixtures was put in a distillation flask and subjected to single distillation.

In addition, the distillation advance, the distillate, and the residual residue at the time of this distillation were analyzed with the gas chromatograph.

The results are shown in Table 4 in Example 3.

In Table 4, only a part of the compounding ratios changed per wt% is extracted and published.

When comparing the composition before distillation and the composition of the distillate, hexamethyldisiloxane was in the range of 70.0-55.0 wt% and ethanol 30.0-45.0 wt%, and the composition change was 5 wt% or less, and the composition change was 5 wt%. The effluent can be carried out as an azeotropic composition as in Example 2, hereinafter referred to as the preparation of Example 4.

Moreover, also in this Example 4, a stabilizer can be added like Example 1.

Example 5

In Example 5, inspection of the manufactured products of Examples 2, 3 and 4 will be described.

First, the oil of Example 2 and the manufactured product of Example 3 were placed in a hand wrap and used as a finishing liquid for hand washing.

These plastics were hand-washed using the respective plastic sheets of PMMA (polyethyl methacrylate), glass garden PC (polycarbonate), PP (polypropylene) and ABS (acrylonitrile-butadiene-styrene). The surface of the board was cleaned by hand.

As a result, there was no problem such as turbidity for the plastic sheet.

Then, the test piece of 5 × 50 × 2 mm size made of plastic was put in a glass bottle, filled with 100 g of the mixed solution of Example 2 in which the compounding ratio was changed by 1 wt%, and left for 48 hours at room temperature and humidity, and taken out to change the weight of each test piece and The change in appearance was investigated.

As a comparative example, a mixed solution of ether and ethanol (ether: ethanol = 3: 1) and pron 113 were also used.

The results are shown in Table 5.

In this table, ○ indicates the results of weight change of less than 1%, no cracking and dissolution occurrence, and Δ of weight change of 1% or more and cracking and dissolution.

In addition, in Table 5, only 1 part of the compounding ratio for every 1 wt% of hexamethyldisiloxane and ethanol is added.

In addition, glass lenses, plastic lenses made of PMMC and PC, and aluminum were washed with the following means as cleaning materials.

In other words, first, the washings were degreased while applying ultrasonic waves with an alkali gum reagent, and then degreased again while applying ultrasonic waves with a surfactant.

Subsequently, water was washed with ultrasonic water to remove the surfactant, followed by ultrasonication with pure water to remove ions and dirt from the water, and the cleaning effect was enhanced.

And it wash | cleaned with IPA as a remover of pure water.

Thereafter, the oil obtained in Example 2 and the prepared product of Example 4 were used as the finishing liquid for finishing, and the washings were immersed in this drying liquid and taken out and dried.

Following the above process, the finishing test of the washing | cleaning material was done.

In this case, IPA steam was used for finishing drying as a comparative example.

Both the fractions of Example 2 and the preparations of Example 4 resulted in good results without deterioration of the washings and residues in the washings.

Example 6

Commercially available hexamethyldisiloxane was purified by distillation, rectification, and adsorbent to remove siloxanes, which are less volatile than dodecamethylpentasiloxane, mixed as impurities.

The purity of hexamethyldisisiloxane obtained by this purification was analyzed by gas chromatography, and the result was 99.5% or more.

In addition, the viscosity of this hexamethyldissiloxane was 0.65 cSt (25 degreeC).

Thus, 200 g of a mixture of purified hexamethyldisiloxane and a weight ratio of 1: 1 in methanol was put in a distillation flask, and the mixture was distilled under normal pressure using a 30-step theoretical column.

By this distillation, an azeotropic fraction was obtained at 58.7 占 폚.

The fraction was analyzed by gas chromatography and found to have a composition of 58.9-59.3 wt% in hexamethyldisiloxane and 40.7-41.1 wt% in methanol.

In addition, a composition of 30-95 wt% of hexamethyldisiloxane and 5-70 wt% of methanol was prepared as an azeotropic composition.

In addition, in this Example, a stabilizer can be added.

As the stabilizer, for example, aliphatic nitro compounds such as nitromethane, nitroethane, nitrobutane, acetylene alcohols such as 3-methyl-1-butyl-3-ol and 3-methyl-1-penten-3-ol, glycy Epoxides such as stone, methylglycidyl ether, arylglycinyl ether, phenylglycidyl ether, 1.2-butylene oxide, cyclohexene oxide, epichlorohydrin, dimethoxymethane, 1.2-dimethoxyethane, Unsaturated hydrocarbons such as 1.4-dioxene, 2.4.4-trimethyl-1-pentene, pentadiene, octadiene, cyclohexene, cyclopentene, aryl alcohol, 1-butene-3-ol, 3-methyl-1-butene Olefin alcohols such as -3-ol-, acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, phenol, trimethyl phenol, cyclohexyl phenol, thymol, 2.6-di-t-butyl-4-methyl phenol, Phenols, such as butylhydroxyanisole and iso igenol, hexylamine, benzylamine, dipropylamine, diisopropylamine, Diisobutylamine, triethylamine, tributylamine, pyridine, n-methylmorpholine, cyclohexylamine, 2.2.6.6-tetramethylpiperidine, N, N'-diaryl-P-phenylenediamine At least 1 sort (s) chosen from amine, benzotriazole, triazole, such as 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, chloro benzotriazole, etc. can be used.

By adding such a stabilizer, it is possible to give more stable characteristics without confirming chloride, such as performance.

Example 7

200 g of a mixture of the weight ratio 1: 1 of hexamethyldisisiloxane and 2-propanol purified in Example 6 was placed in a weight flask and distilled under normal pressure using a 30-step theoretical column.

By this distillation, an azeotropic fraction was obtained at 76.4 占 폚.

The fraction was analyzed by gas chromatography and found to have a composition of 54.1-54.5 wt% in hexamethyldisiloxane and 45.5-45.9 wt% in 2-propanol.

In addition, an azeotropic composition having a composition of 25-95 wt% of hexamethyldisiloxane and 5-75 wt% of 2-propanol was prepared.

Also about these, the stabilizer and / or solvent shown in Example 6 can be added, and these addition can increase the more stable characteristic and dissolving power, without degrading performance.

Example 8

In the present Example, the test | inspection of the composition of Example 6 and Example 7 is demonstrated.

First, the oil of Example 6 and Example 7 and the composition of the same composition were put into the hand wrap container, and it was used as the finishing liquid for hand washing.

As a hand washing object, the surface of these plastic boards was hand-washed with each plastic board which consists of PMMA, glass garden PC, PP, and ABS.

As a result, there was a problem such as turbidity for all plastic sheets.

Then, put the 5 × 50 × 2mm sized specimens of each plastic in a glass bottle, filled with 100g of the mixed solution of the composition shown in Table 6 and left for 48 hours at room temperature and humidity, and take out the weight change and appearance change of each specimen Investigated.

As a comparative example, a mixed solution of ether and ethanol (ether: ethanol = 3: 1) and pron 113 were also used.

The results are shown in Table 6.

In this table, ○ is less than 1% by weight change, no cracking and dissolution occurs, △ is not less than 1% by weight, no cracking and dissolving, × is more than 1% by weight, cracking and melting Each result of occurrence is shown.

The compositions of Examples 6 and 7 were placed in a hand wrap container, soaked in an appropriate amount into a clean wipe paper from the hand wrap container, and the optical lens to which the washing oil after processing was applied with the clean wipe paper was hand-washed.

As a result, the washing oil can be completely removed, and the optical lens can be cleaned, and at the same time, good results are obtained without occurrence of spots on the optical lens.

In addition, good results were obtained when the equivalent tests were carried out with the azeotropic compositions of Examples 6 and 7.

In addition, glass lenses, plastic lenses made of PMMC and PC, and aluminum were washed in the following order as the object to be cleaned.

That is, first, the cleaning material was degreased while applying an ultrasonic wave with an alkali gum agent, and then degreased again while applying an ultrasonic wave to the surfactant.

Subsequently, water was washed with ultrasonic water to remove the surfactant, followed by washing with pure water to remove the ions and contaminants, and the degree of cleaning was increased.

The pure water was washed with IPA (2-propanol).

Subsequently, the oil and azeotropic compositions obtained in Examples 6 and 7 were used as the drying liquid for finishing, and the washings were immersed in this drying liquid and taken out and dried.

After the above process, the finishing inspection of the washing | cleaning material was performed.

In this case, IPA steam was used for finishing drying as a comparative example.

Also in both the oil component and the azeotropic composition of Examples 6 and 7, there was no deterioration of the cleaning matter or residues in the cleaning product and good results were obtained.

Example 9

The plastic lens made of glass lens, PMMA and PC, and the metal parts made of aluminum were washed in the following procedure.

First, the cleaning material was degreased while applying ultrasonic waves in an alkali check agent, and then degreased again while applying ultrasonic waves in the surfactant.

Subsequently, washing with water by adding ultrasonic waves with a constant to remove the surfactant, followed by washing with ultrasonic waves with pure water to remove ions and contamination of the constant water to increase the degree of cleaning.

And it wash | cleaned with IPA as pure water removal.

Finally, the effluent obtained using the octamethyl trisiloxane was obtained by using a distillator of 30 or more theoretical stages as the finishing drying liquid, and the resultant was immersed in the drying liquid, and then air-dried.

The resultant drying solution used in the present invention was analyzed by gas chromatography, and found to be 0.009% of dodecamethylpentasiloxane and less volatile compounds than dodecamethylpentasiloxane.

Analysis conditions for gas chromatography were performed using gas chromatography under the trade name GC14A (manufactured by Shimadzu Corporation), with an injection temperature of 260 ° C, a detection temperature of 280 ° C, and a temperature of 50 ° C to 250 ° C. It heated up at 10 degree-C / min, and performed using the FID detector and OV-1-capillary column.

Binocular stereomicroscope and aerobic tests were conducted to evaluate the finish and dry conditions.

As a result, stains and residues could not be confirmed and favorable finish drying could be performed.

In addition, instead of octamethyltrisiloxane, good results are obtained by octamethylcyclotetrasiloxane which is 0.008wt% or less of dodecamethylpentasiloxane and is substantially free of volatile compounds than dodecamethylpentasiloxane. Obtained.

Example 10

The glass lens, the plastic lens of PMMC and PC, and the metal parts of aluminum were wash | cleaned in the following procedures.

First, the cleaning material was degreased while applying ultrasonic waves in an alkaline saponifier, and then degreased again while applying a surfactant ultrasonic wave.

Subsequently, washing with water by adding ultrasonic waves to a constant removes the surfactant, and again by applying ultrasonic waves to the pure water to remove ions and contamination of the constant, thereby increasing the degree of cleaning.

And it wash | cleaned with IPA as pure water removal.

Finally, the effluent obtained using octamethylcyclotetrasiloxane by using a distillator of 30 stages or more of the theoretical stage was used as a finishing drying liquid, and the cleaning solution was immersed in this drying liquid, and the resultant was dried by blowing air.

The finishing drying solution used in this example was analyzed by gas chromatography. As a result, no compound was found to be 0.009% of dodecamethylpentasiloxane and worse in volatility than dodecamethylpentasiloxane.

Also in the present Example, it carried out by binocular stereomicroscope and aerobic test like Example 9 as evaluation of the finish dry condition.

As a result, stains and residues could not be confirmed and favorable finish drying was possible.

Example 11

The glass lens, the plastic lens of PMMC and PC, and the metal parts of aluminum were wash | cleaned in the following procedures.

First, the to-be-cleaned object was degreased by adding ultrasonic waves in an alkali check agent, and then degreased again by adding ultrasonic waves in surfactant.

Thereafter, water was washed with ultrasonic constant water to remove the surfactant, and the ultrasonic water was added to the pure water for washing to remove ions and contaminants in the constant water and to increase the degree of cleaning.

And it wash | cleaned with IPA as pure water removal.

Here, as an alkali validating agent, the brand name EE-1120 (product of Olympus Kogaku Kogyo Co., Ltd.) which is an alkaline aqueous detergent, and the brand name EE-1110 (product of Olympus Kogaku Kogyo Co., Ltd.) which are aqueous surfactants are respectively used as surfactant. 8 dilutions were used.

In addition, the ultrasonic wave generator used the thing of the output of 28H and 600W.

The tank was divided into three sections, and the constitution of the tank was made of Article 2 of alkali saponification, Article 2 of surfactant activity, Article 3 of pure water and Article 2 of IPA.

Finally, the effluent obtained using octamethyltrisiloxane was used as a rinse liquid by distillation using 30 or more stages of distillation as the rinse liquid, was taken out, and then steam washed with perfluorocarbon (boiling point 80 ° C.) of the basic chemical formula CF.

The rinse solution used in this example was analyzed by GC, and found to contain 0.009% of dodecamethylpentasiloxane and more than dodecamethylpentasiloxane (polymeric straight chain siloxane, dodecamethylcyclohexasiloxane and dode). Cyclic siloxanes of polymers and organic compounds having molecular weights equivalent to or higher than those of carmethylcyclohexasiloxane were not found.

The analysis by GC was carried out using a trade name GC14A (manufactured by Shimatsu Seisakusho Co., Ltd.) at an injection temperature of 260 ° C and a detector temperature of 280 ° C, and the temperature was increased from 50 ° C to 250 ° C at 10 ° C / min, and the FID detector and OV. -1-capillary column was used.

Binocular stereomicroscope and aerobic tests were carried out as evaluation of the finish dry state.

As a result, stains and residues were not confirmed, and it was confirmed that they were in a good finish and drying condition.

Example 12

The glass lens and the aluminum metal component were washed in the following procedure.

First, the to-be-cleaned object was degreased by applying ultrasonic waves in an alkali check agent, and then degreased again by applying ultrasonic waves in a surfactant.

Thereafter, water was washed with ultrasonic constant water to remove the surfactant, and again, ultrasonic water was added to the pure water to remove the ions and contaminants, thereby increasing the degree of cleaning.

And it wash | cleaned with IPA as pure water removal.

These treatments were carried out under the same conditions as in Example 11.

The effluent obtained by distillation of octamethylcyclotetrasiloxane using a distillator of 30 or more theoretical stages was immersed and dried, and then steam-washed with perfluorocarbon (boiling point 102 ° C) of the basic chemical formula CF.

The rinse solution used in this Example was analyzed by GC, and found to contain 0.009% of dodecamethylpentasiloxane, and the straight chain siloxane, dodecamethylcyclohexasiloxane, and dodeca of polymers more than dodecamethylpentasiloxane. Cyclic siloxanes of polymers and organic compounds having molecular weights equal to or higher than those of methylcyclohexasiloxane were not found.

In addition, analysis conditions by GC are the same as in Example 11.

Binocular stereomicroscope and aerobic tests were carried out as in Example 11 to evaluate the finish and dry conditions.

As a result, it was confirmed that stains and residues were found to be in a good finish and dry state.

Example 13

The glass lens, the plastic lens of PMMC and PC, and the metal parts of aluminum were wash | cleaned in the following procedures.

First, the to-be-cleaned object was degreased by adding ultrasonic waves in an alkali check agent, and then degreased again by adding ultrasonic waves in surfactant.

Thereafter, water was washed with ultrasonic water to remove the surfactant, and the surfactant was washed while ultrasonic water was added to the pure water to remove ions and contaminants of the water to increase the degree of cleaning.

And it wash | cleaned with IPA as pure water removal.

These treatments were carried out under the same conditions as in Example 11.

Then, the distillate obtained using a decane tetrasulfate of 30 or more theoretical plates was immersed and taken out as a rinse liquid, and then steam washed with perfluorocarbon (boiling point of 56 ° C.) of the basic chemical formula CF.

The rinse liquid used in this example was analyzed by GC, and the content of dodecamethylpentasiloxane was 0.008 wt%, which is a straight chain siloxane and dodecamethylcyclohexasiloxane of polymer than dodecamethylpentasiloxane. And cyclic siloxanes of polymers and organic compounds having molecular weights equal to or higher than those of dodecamethylcyclohexasiloxane.

In addition, analysis conditions by GC are the same as in Example 11.

Binocular stereomicroscope and aerobic test were done like Example 11 as evaluation of the finish dry state.

As a result, stains, residues, etc. were not confirmed, and it was confirmed that it was in a good finish dry state.

In addition, the low molecular weight siloxane before steam cleaning used in Examples 11, 12, and 13 had a content rate of dodecamethylpentasiloxane less than 0.001 wt%, and was a straight chain siloxane and dode of polymers more than dodecamethylpentasiloxane. Since the cyclic siloxanes of polymers are substantially removed from carmethylcyclohexasiloxane and dodecamethylcyclohexasiloxane, the low molecular weight siloxane attached and the perfluorocarbon, a steam cleaner, are attached when steam cleaning the object to be cleaned. The usability with the resin is good, and a good substitution is possible, and the finishing drying becomes favorable.

In Examples 11, 12, and 13, hexamethyldisiloxane can be used.

The hexamethyldissiloxane can be used alone because of its good volatility, but can be added to steam cleaning using perfluorocarbons as part of a cleaning and drying system.

[Attack evaluation]

Then, the effect on the plastic which is a material of the to-be-cleaned object was evaluated using the low molecular weight siloxane which was used in Example 9-13 mentioned above.

In this evaluation, each test piece (5 × 50 × 2 mm) of acrylic resin (PMMA), glass filler-containing polycarbonate, polypropylene resin (PP), and acrylonitrile-butadiene-styrene (ABS) was placed in a glass bottle. After filling with the low molecular weight siloxane solution of Example 9-13, and leaving for 48 hours at room temperature and humidity, the weight change and the appearance change were examined.

It examined similarly using the Fron 113 (made by Daishin Koyo Co., Ltd.) and IPA as a comparative example.

The results are shown in Table 7.

In this table, ○ indicates that the weight change is less than 1%, Δ indicates that the weight change is 1% or more and there is no appearance change, and × indicates that the weight change is 1% or more and there is an appearance change such as a crack.

Example 14

FIG. 1 shows a flowchart of an example of drying without using drying by IPA paper, and immersion in a non-aqueous solvent such as low molecular weight siloxane is used for drying.

In the cleaning process shown in this drawing, organic matter contamination such as cutting oil, fingerprint, and inorganic contamination such as cerium oxide and dust attached to the object to be cleaned which is an optical part of the lense is removed with a detergent.

In the rinse process, the detergent is washed with constant or pure water.

In the dehydration step, the water attached to the washings is replaced with IPA.

In the drying step, the object to be cleaned is immersed in a non-aqueous solvent to replace IPA with a non-aqueous solvent.

After finishing, clean air is dried by clean air or dried by paper under reduced pressure.

Warm air drying is performed after immersing IPA used in the dehydration step in a non-aqueous solvent such as low molecular weight siloxane.

That is, the low molecular weight siroxane is blown through clean air (80 ° C) passing through the HEPA filter to the object to be cleaned including optical components such as lenses and prisms immersed in the low molecular weight siloxane, or passed through the clean water in a clean air atmosphere. To vaporize.

In steam drying under reduced pressure, the low molecular weight siloxane is introduced into a vaporized state in a reduced pressure atmosphere and dried.

Steam drying under this reduced pressure is carried out in a closed system, as described in Example 15 described later.

Examples of the low molecular weight siloxane used for steam drying under reduced pressure include octamethyltrisiloxane, hexamethyldisiloxane, and octamethylcyclotetrasiloxane, and those commercially available products are distilled and purified to have a high purity of 99.9% or more.

Since these low molecular weight cipoic acids have their own degreasing power, not only can they be cleaned and dried at a high quality, but also minor contamination and grease can be removed only by steam drying under reduced pressure.

2 and 3 show a regenerating apparatus for non-aqueous solvent such as low molecular weight siloxane used in the drying step of this embodiment.

In FIG. 2, 11 is a washing tank and consists of the inner tank 12 and the outer tank 13, and the ultrasonic oscillator 14 is provided in the center of the outer bottom of the outer tank 13. As shown in FIG.

The outer tank 13 receives the non-aqueous solvent 15, such as the low molecular weight siloxane which flowed out from the inner tank 12, and has a non-aqueous system at the bottom of the outer tank 13 in the space | interval of the inner tank 12 and the outer tank 13. The recovery pipe 16 of the solvent 15 is connected.

The recovery pipe 16 is connected to the lower part of the separation tank 17, and the tip thereof becomes the non-aqueous solvent discharge pipe 18, and is extended in the separation tank 17. In the separation tank 17, the non-aqueous solvent 15 and the separation liquid 19 made of water are accumulated in a state where they are separated up and down according to the specific gravity difference. The non-aqueous solvent discharge pipe 18 is located in the receiving portion of the separation liquid 19 accumulated below the separation tank 17, and the IPA contained in the non-aqueous solvent 15 recovered by the recovery pipe 16 is separated. In order to efficiently dissolve in the liquid 19, a plurality of discharge holes 20 (see FIG. 3) are opened.

The regeneration liquid circulation pipe 21 is connected to the right side of the separation tank 17 containing the non-aqueous solvent 15, and the other side is connected to the bottom of the inner tank 12 at the bottom of the outer tank 13.

A pump 22 and a filter 23 are arranged in the regeneration liquid circulation pipe 21 to circulate the non-aqueous solvent 15 in the path of the washing tank 11 → separation tank 17 → washing tank 11. have.

The filter 23 is for removing particulates from the liquid.

The separation tank 17 is provided with a top cover 24, and the top cover 24 is a supply tank for the float switch 25 to the sensor for detecting the liquid level of the non-aqueous solvent 15 and the new non-aqueous solvent 15 ( A supply pipe 27 communicating with 26 is attached.

The valve 28 is installed in the supply pipe 27 and the valve 28 is opened when the liquid level decrease of the non-aqueous solvent 15 is detected by the float switch 25. The non-aqueous solvent 15 is supplied from the supply tank 26. ) Is supplied to the separation tank (17).

The separation liquid supply pipe 29 and the separation liquid discharge pipe 30 are connected to the bottom of the separation tank 17.

The separation liquid supply pipe 29 is connected to a pure water supply device (not shown), and the separation liquid discharge pipe 30 is connected to a waste storage tank (not shown).

Valves 31 and 32 are provided in the separation liquid supply pipe 29 and the separation liquid discharge pipe 30, respectively, so that the separation liquid 19 is freely supplied and discharged.

In the separation tank 17, water supplied from the pure water supply device through the separation liquid supply pipe 29 is contained as half the separation liquid.

In the regeneration apparatus of the above structure, in the dehydration step of the previous step, the IPA attached to the washing matter is immersed in the non-aqueous solvent 15 of the inner tank 12 of the washing tank 11, It is dissolved in the non-aqueous solvent 15, incorporated and separated from the object to be washed.

The non-aqueous solvent 15 of the IPA mixing flowing out from the upper portion of the inner tank 12 and flowing into the outer tank 13 is separated from the discharge hole 20 of the non-aqueous solvent discharge pipe 18 through the recovery pipe 16. Emitted during (19).

The separation liquid 19 has higher compatibility with the IPA than the non-aqueous solvent 15, so that when the non-aqueous solvent 15 reaches the top surface through the separation liquid 19 to the upper surface in the distribution equilibrium, the IPA in the non-aqueous solvent 15 Is dissolved in the separation liquid 19, and the liquid layer of the regenerated non-aqueous solvent 15 floats on the separation liquid 19.

In addition, since the discharge hole 20 is small, the non-aqueous solvent 15 discharged from the discharge hole 20 becomes small particles and floats in the separation liquid 19.

In this flotation process, the contact area between the non-aqueous solvent and the separation liquid increases, and IPA in the non-aqueous solvent is efficiently recovered in the separation liquid.

The non-aqueous solvent 15 in the upper layer of the separation tank 17 is supplied into the inner tank 12 from the bottom of the washing tank 11 through the regeneration circulation pipe 21.

On the other hand, the separation liquid 19 mixed with IPA is periodically discharged to the discharge storage tank through the separation liquid discharge pipe 30, and is supplied through the separation liquid 19 from the pure water supply device, the separation tank 17 The liquid level of the separation liquid 19 in the C) is constant, and the concentration of IPA to be mixed is kept below a certain level.

Using this regeneration apparatus, the IPA concentration in the regenerated non-aqueous solvent (15) was analyzed by gas chromatography. As a result, when the continuous purification was performed without using the regeneration apparatus, the non-aqueous solvent in which the IPA concentration gradually increased was regenerated. Using it was confirmed that the IPA concentration is maintained at less than 1%.

Table 8 shows the safety when hexamethyldisiloxane was selected as the non-aqueous solvent of Example 14 and compared with IPA vapor.

In addition, similar effects were obtained in the case where octamethyltrisiloxane and octamethylcyclotetrasiloxane were used as the non-aqueous solvent.

4 shows another regeneration apparatus for regenerating a non-aqueous solvent.

In this figure, an outlet tank 60 is installed in a drying tank 51 filled with a non-aqueous solvent used for drying the object to be cleaned, and a separation tank 52 is connected to the outlet tank 60 through a pipe. have.

The separation tank 52 is separated by the separating plates 73 and 74 and has a three-joint structure consisting of the first tank 52a, the second tank 52b and the third tank 52c.

These tanks are made low in the order of Article 1 (52a), Article 2 (52b), and Article 3 (52c), and the low tank is to receive the overflowed non-aqueous solvent from the high bath.

Article 52a separates the non-aqueous solvent from the hydrophilic solvent mixed in the solvent, and the pure water 77 as a separation liquid is filled therein.

The non-aqueous solvent from the outflow tank 60 is supplied into the 1st tank 52a by the liquid inlet 72 provided in the lower part of this 1st tank 52a.

Plural separation plates 71 are provided in the first tank 52a.

The plurality of separation plates 71 are installed inside the first article in a state in which they are opposed to each other and are inclined, and the non-aqueous solvent 78 supplied from the liquid inlet 72 is separated according to the specific gravity difference with the pure water. It rises along 71 and is stored in the upper part of the first tank 52a, and flows out into the second tank 52b.

In the second tank 52b and the third tank 52c of the separation tank 52, the partition plates 61 and 62 which separate the non-aqueous solvent flowing into each tank and the non-aqueous solvent flowing out of the tank are not mixed. ) Are installed vertically.

These 2nd tank 52b and 3rd tank 52c are tanks which isolate | separate the water in non-aqueous solvent 78 and non-aqueous solvent by specific gravity difference.

In this case, the third level 52c is provided with a liquid level sensor 76 that detects the liquid level of the upper and lower limits in the third level 52c, so as to detect whether the non-aqueous solvent is above or below a predetermined amount. It is.

The tanks 52a, 52b, and 52c are provided with discharge valves 53 for wiping and refilling the liquid in the tanks, and when the tanks 52a are disposed, the drain valves 59 It is installed.

80 is a pump connected to the outlet 75 of the third tank 52c of the separation tank 52, and is used to circulate the liquid in the apparatus.

The drying tank 51 is connected to the pump 80 through the filter 79.

57 is a replenishment tank for replenishing a new non-aqueous solvent, and is connected to the liquid outlet 75 in the third tank 52c of the separation tank 52 through the replenishment valve 58.

56 is a controller which controls whether or not fresh non-aqueous solvent is supplied in response to a signal from the liquid level sensor 76 and performs opening and closing of the replenishment valve 58.

83 and 84 are liquid level sensors arranged in the upper hole of the first tank 52a of the separating tank 52.

As the liquid level sensors 83 and 84, a capacitive sensor or the like for measuring the conductivity of the liquid in the first tank 52a is used.

The upper liquid level sensor 83 detects an interface between the non-aqueous solvent 78 and the pure water 77.

In other words, when the amount of pure water 77 in the first tank 52a increases and reaches the height of the liquid level sensor 83, the liquid level sensor 83 detects this.

In this way, the discharge valve 59 is automatically opened to discharge the pure water 77.

Therefore, in the first tank 52a, the liquid amount of the pure water 77 does not increase than the liquid level sensor 83, so that the pure water 77 flows out of the first tank 52a to the second tank 52b. Does not flow

The lower liquid level sensor 84 detects this amount when the amount of pure water 77 is reduced by this discharge and the interface with the non-aqueous solvent 78 reaches the liquid level sensor 84.

In this way, the discharge valve 59 is automatically closed and discharge of pure water is stopped.

Therefore, the pure water amount in Article 2 (52b) does not become a fixed amount or less, and the separation action by pure water can be maintained.

In addition, a valve (not shown) for supplying the pure water 77 is connected to the first article 52a, and the replenishment is performed so that the pure water 77 maintains a constant amount.

Next, the operation when the viscosity 1CSt (25 DEG C) is used as octamethyltrisiloxane and the hydrophilic solvent IPA (hereinafter referred to as alcohol) as the low molecular siloxane of the non-aqueous solvent will be described.

In this case, fresh octamethyltrisiloxane of 99.9% purity is stored in the replenishment tank 75.

As a new still life, using a barrel glass with washing oil (Yushiron Chemical Co., Ltd.) and washing oil attached, wash this lens with detergent → rinse with water → dehydrate with alcohol, and then dry the tank (51). It is dried by octamethyl trisiloxane in the) and finishes.

The IPA concentration in the octamethyltrisiloxane which flowed out from the drying tank 51 by this washing | cleaning becomes 1.0 wt%, and enters the 1st tank 52a of the separation tank 52 from the liquid inlet 72 through a pipe.

The octamethyltrisiloxane (51) mixed with this alcohol is separated and floated due to the specific gravity difference in the pure water (77) previously filled in the first tank (52a).

This floating alcohol-incorporated octamethyltrisiloxane is raised in the pure water 77 according to the separator 71 attached obliquely in the first tank 52a.

In this ascending process, the alcohol component is absorbed into the pure water 77 in the octamethyltrisiloxane 55 mixed with alcohol.

If this is repeated, the alcohol in the octamethyltrisiloxane (51) mixed with alcohol is removed, and the octamethyltrisiloxane (78) of low alcohol concentration is floated.

At this time, the alcohol concentration and water content in octamethyltrisiloxane were measured by gas chromatography and Karl Fischer moisture meter, and the alcohol concentration and water concentration were 0.7% in total.

When the floating octamethyltrisiloxane (78) is excessively accumulated, the octamethyl trisiloxane (78) overflows Article 1 (52a) and flows into Article 2 (52b).

This octamethyltrisiloxane (78) flows in the process of re-separation and the water is separated by the specific gravity difference, and water is accumulated at the bottom of the tank.

In general, in the production process, the inflow of alcohol and water to Article 1 (52a) is increased, and only the Article 1 is insufficient to remove alcohol in the non-aqueous solvent.

For this reason, a non-aqueous solvent flows into the 2nd tank 52b and 3rd 52c which isolate | separate by specific gravity difference.

If the octamethyl trisiloxane 78 which has been separated and injured here is accumulated, it will flow into the third tank 52c beyond the second tank 52b.

The concentration which added alcohol and water when it came out from Article 2 was 0.5%.

Thus, in Article 3, octamethyltrisiloxane (78) having a concentration of 0.2% added with alcohol and water is stored.

Regeneration of the octamethyltrisiloxane (78) proceeds in this way, and the regenerated octamethyltrisiloxane is sucked by the pump from the liquid outlet (75) and sent to the drying tank (5) again.

In this manner, the rinsing tank 51 can store the octamethyltrisiloxane 90 from which alcohol has always been removed.

In addition, when the amount of octamethyl trisiloxane is reduced by evaporation, the liquid level sensor 76 detects and the supply valve 58 of the supply tank 57 is opened by the controller 66, and a new octamethyl tricy having a purity of 99.8%. Roxane is popular.

In addition, when the inflow of the hydrophilic solvent into the drying tank increases, the total liquid amount increases, and the liquid level sensor 76 also serves to open the discharge valve 59 by the controller 56, and the water is drained to obtain an appropriate liquid amount.

In addition to the octamethyltrisiloxane used here, the purity used in Examples 9 and 10 may be similarly used. In addition, the same effect can be acquired also in hexamethyl disiloxane and octamethyl trisiloxane.

Example 15

FIG. 5 shows an apparatus for supplying a non-aqueous solvent such as low molecular weight siloxane in a vapor form under reduced pressure to perform cleaning and drying of the object to be cleaned.

The apparatus is divided into a washing and drying means 100, a recovery means 200 and a steam generating means 300 so as to be divided into two dashed lines. The washing and drying means 100 performs degreasing washing or fine washing and drying of the object to be cleaned 400, and in addition, washing and drying is continuously performed. The cleaning and drying means 100 includes a cleaning drying unit 110 in which the inside thereof is sealed by the closing of the cover 111 that can be opened and closed, and the object to be cleaned 400 is installed in the cleaning drying unit 110. The receiving material 112, such as a net and a shelf, is provided in single | stage or multistage type. In addition, an insulation heater 113 is disposed at the outer side of the side and bottom of the washing and drying 110 to maintain the washing and drying 110 at a predetermined temperature. Condensation of the vapor of the non-aqueous solvent in the washing and drying 110 is prevented by the heating operation of the insulating heater 113. The cleaning drying 110 is to clean and / or dry the object to be cleaned by vapor of a non-aqueous solvent under a reduced pressure, and the leak valve 114 for changing the inside of the cleaning and drying 110 from a reduced pressure to an atmospheric pressure. ) Is installed.

The recovery means 200 has a separation tank 120 and a tank 121 connected to the separation tank 120. The separation tank 120 is sealed with a cover 20a, and water W is stored therein. Separation tank 120 is provided with a circulation path 122 for circulating the water (W) to the separation tank 120. In this circulation path 122, a vacuum pump 123, which is a water-sealed pump for supplying steam or condensate of non-aqueous solvent from the washing and drying 110, to the separation tank 120, is disposed. Referring to the circulation path 122 according to the path, 24 is a discharge valve, 125 is a filter for filtering foreign matter, 26 is a pump for supplying water to the vacuum pump 123, 127 is a ratio from the vacuum pump 123 A condenser for cooling a mixture of an aqueous solvent and water to promote liquefaction. In addition, the coil-like cooling tube 128 for cooling is installed in the separation tank 12, and an inlet pipe for introducing the mixed liquid passed through the vacuum pump 123 and the condenser 127 into the water tank W ( 129 is installed. The separation tank 120 is for separating the non-aqueous solvent and water by the difference in specific gravity, the non-aqueous solvent having a small specific gravity rises in the upper layer of the water tank (W). By this separation, the non-aqueous solvent in the washing and drying 110 is recovered in the separation and separation tank 120 in both the vapor form and the liquid form. The tank 121 connected to the separation tank 120 has a sealed structure in which only the non-aqueous solvent separated in this way is supplied and temporary oil storage for reuse is performed.

The steam generating means 300 is provided with a steam generating tank 130 and a heater 131. The steam generator 130 has a non-aqueous solvent stored therein, and is provided with a heating coil 132 for supplying high temperature and high pressure steam from the heater 131 to heat the non-aqueous solvent. Reference numeral 133 denotes a level gauge for detecting the liquid level of the non-aqueous solvent in the steam generator 130, and the supply of the non-aqueous solvent in accordance with the detection value of the level gauge 133 is performed. The heater 131 has a heater 131a and heats the heat medium installed therein. As the heater 131, an electric boiler, a factory steam, or other heating mechanism can be selected. In the illustrated example, an electric boiler is used. The heater 131 is connected to the hot water tank 134 and connected to the hot water tank 134 so that hot water in the tank 134 is supplied to the heater 131 by the pump 135 and heated. This heating furnace hot water is vaporized and sent to the heating coil 132 of the steam generating tank 130 to heat the non-aqueous solvent in the generating tank 130 to steam. The steam after heating becomes a liquid solidified in the auto trap 136, and is recovered and reused in the hot water tank 134. In addition, the liquid level of the hot water in the hot water tank 134 is detected by the liquid level gauge 137 so that a predetermined amount is always stored.

The cleaning and drying means 100, the recovery means 200, and the steam generating means 300 as described above are connected by a pipe line described below, and a closed system in which the non-aqueous solvent is circulated is configured. First, the cleaning drying means 100 and the recovery means 200 are connected to two systems, the main pipe and the auxiliary pipe. The main pipe is connected to the bottom of the washing and drying 110 and the vacuum pump 123 of the recovery means 200, the pipe 151 for discharging the liquid non-aqueous solvent condensed in the washing and drying 110, The upper portion of the washing and drying 110 and the vacuum pump 123 is connected to the conduit 152 for discharging the vapor of the non-aqueous solvent. Exhaust valves 153 and 154 for opening and closing are provided in these conduits 151 and 152, and condensers 155 are provided in the conduits 152 to cool and liquefy steam.

On the other hand, as shown in the dashed-dotted line, the auxiliary pipe line includes a conduit 156 for connecting the bottom of the washing and drying dryer 110 and the exhaust valve 154 of the pipeline 152 of the main pipe and the washing and drying 110. It becomes a conduit 159 which directly connects the tank 121 of the bottom part and the recovery means 200, and an exhaust valve 157 and a condenser 158 are provided in the conduit 156. These main and auxiliary pipes may be used alternatively or simultaneously depending on the discharge conditions of the non-aqueous solvent in the washing and drying 110.

Piping path connecting the recovery means 200 and the steam generating means 300 to the pipe line 160 between the tank 121 of the recovery means 200 and the steam generating tank 130 of the steam generating means 300. It is composed. The pipeline 160 is provided with a liquid feed pump 161, a filter 162 for removing foreign matter by filtration, an automatic valve 163, and a non-return valve 164. The liquid supply pump 161 operates on the basis of the detection signal of the level gauge 133 of the steam generator 130 and supplies the non-aqueous solvent in the tank 121 to the steam generator 130. The liquid feeding pump 161 is controlled to operate when the non-aqueous solvent in the steam generator 130 reaches a predetermined lower limit, and to stop when the non-aqueous solvent reaches the predetermined upper limit.

Piping path connecting the steam generating means 300 and the washing and drying means (1) is composed of a conduit 170 for connecting the steam generating tank 130 and the washing and drying drying 110, the air supply to this conduit 170 The valve 171 is provided. In addition, an air supply valve 172 and a cooking valve 173 are disposed in parallel with the air supply valve 171 in the conduit 170. 180 is a temperature controller installed in the steam generator 130 and the heater 131, 181 is a pressure controller for detecting and controlling the pressure of the steam generator 130 and the heater 131.

Examples of the non-aqueous solvent used in this apparatus for cleaning and drying the object to be cleaned 400 include low molecular straight chain or cyclic siloxane compounds, hydrocarbon compounds such as terpenes, IPA (isopropyl alcohol) and ethanol. Alcohols and other compounds can be appropriately selected and used, but hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane are particularly preferable. These solvents are flammable, but since the whole apparatus is a closed system, safe washing or drying can be performed without volatilizing to the outside. First, the cleaning object 400 is fixed on the receiving member 112 of the cleaning and drying 110 in a state where the cleaning and drying 110 is warmed by the warming heater 113, and the cover 111 is closed. Seal it. In addition, the thing to be cleaned may be applied by washing with a surfactant, rinsing with a constant, or rinsing with pure water, followed by ordinary washing with substitution by IPA, or an untreated one that is not washed.

The exhaust valves 153 and 154 are opened in the closed state of the washing and drying 110 to operate the vacuum pump 123, and thus the inside of the washing and drying 110 is reduced. The exhaust valves 153 and 154 are closed when the pressure is reduced to a predetermined vacuum level. On the other hand, in the steam generating means 300, the non-aqueous solvent in the steam generating tank 130 is heated by the heater 131, thereby generating steam of the non-aqueous solvent. In this state, the air supply valves 171 and 172 of the pipe line 170 are opened, and steam is introduced into the washing and drying 110. The steam is supplied until it reaches a predetermined concentration in the washing and drying 110, thereby washing the object to be cleaned 400 with steam of a non-aqueous solvent.

After the steam cleaning is performed for a predetermined time, the exhaust valves 153 and 154 are opened at the same time as the air supply valves 171 and 172 are locked. At this time, since the vacuum pump 123 is operating, steam and condensate of the non-aqueous solvent in the washing and drying 110 are sucked and removed from the conduits 152, 153, and 156. At this time, the paper is liquefied in the condenser 155 of the conduit 152. The suctioned non-aqueous solvent is mixed with water in the vacuum pump 123 and introduced into the separation tank 120 when the remaining vapor is liquefied in the condenser 127. In this way, the non-aqueous solvent in the washing and drying 110 may be liquefied by the condensers 155 and 127 to improve the recovery rate of the non-aqueous solvent. After suctioning the inside of the washing and drying 110, the leak valve 114 is opened while the exhaust valves 153 and 154 are closed to introduce the atmosphere, and thus, cleaning and drying by steam are finished, Eject 400.

The non-aqueous solvent introduced into the separation tank 120 is separated from water by the specific gravity difference and recovered, and the overflowed non-aqueous solvent is sent to the tank 121. On the other hand, in the steam generating tank 130, the liquid level inside is detected by the level meter 133, and when the liquid level reaches the lower limit, the liquid feeding pump 161 is driven so that the non-aqueous solvent is discharged from the tank 134 by the steam generating tank ( 130, and the replenishment of the shortage proceeds. In addition, the separation tank 120 separates the non-aqueous solvent due to the difference in specific gravity from water, but when using alcohol such as IPA as the non-aqueous solvent, it is possible to separate using the water-alcohol separation device instead of the separation tank 120. It could be.

In this cleaning or drying process, the system is closed, so that the non-aqueous solvent does not leak or diffuse to the outside. This makes it possible to effectively prevent pollution without the non-aqueous solvent contaminating the air or the environment. In addition, since the washing and drying is carried out under reduced pressure, the oxygen is completely blocked and the flammable non-aqueous solvent improves the safety, and at the same time, the washing and drying can be performed at low temperature, and the thermal avoidance to the object to be cleaned can be reduced. In addition, since the non-aqueous solvent is recovered and recycled to the recovery means 200, its useful use is possible. And, when the recovered non-aqueous solvent is vaporized in the steam generating tank 130, it is separated from the maintenance by the difference in boiling point it is possible to circulate use in the state of high purity and can maintain a strong cleaning power and drying power.

As mentioned above, this invention washes and drys a to-be-cleaned object using the low molecular weight siloxane of purity 99% or more, and can process it without a stain or contamination, without invading a to-be-cleaned object. It also does not destroy the ozone layer because it does not use a pron.

Claims (11)

It contains one or more of the low molecular weight siloxanes of hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane, and the content of dodecamethylpentasiloxane is less than 0.01% by weight, A cleaning and drying composition, which is substantially free of compounds having a lower volatility than lactic acid. The composition for cleaning and drying according to claim 1, wherein the hexamethyldisiloxane and one alcohol among ethanol, methanol, and 2-propanol are in an azeotropic or azeotropic state at atmospheric pressure. The composition for cleaning and drying according to claim 2, wherein the hexamethyldisisiloxane is at least 98% pure. The composition for cleaning and drying according to claim 1, which contains at least one of hexamethyldisiloxane, octamethyltrisiloxane and octamethylcyclotetrasiloxane supplied under reduced pressure in the form of a vapor. It contains one or more of the low molecular weight siloxanes of hexamethyldisiloxane, octamethyltrisiloxane, and octamethylcyclotetrasiloxane, and the content of dodecamethylpentasiloxane is less than 0.01% by weight, A cleaning and drying method characterized by using a cleaning and drying composition which is substantially free of compounds having a lower volatility than lactic acid. 6. The cleaning and drying method according to claim 5, comprising the step of regenerating the low molecular weight siloxane used for washing and drying in contact with water or pure water. 6. The method of claim 5, wherein the low molecular weight siloxane is supplied in the form of a vapor under reduced pressure. 8. The cleaning and drying method according to claim 7, further comprising the step of regenerating the low molecular weight siloxane, which is supplied in a reduced pressure in the form of a vapor and used for cleaning and drying, in contact with water or pure water. The rinse in the final step of washing the object to be cleaned contains at least one of hexamethyldisiloxane, octamethyltrisiloxane and octamethylcyclotetrasiloxane, at the same time, and the content of dodecamethylpentasiloxane. Less than 0.01% by weight and immersed in a low molecular weight siloxane that is substantially higher in molecular weight than the straight chain cyclic and cyclic siloxanes and higher molecular weight organic compounds than those of dodecamethylpentasiloxane. Thereafter, the washing and drying method characterized in that the steam cleaning using a perfluorocarbon compound. The washing and drying method according to claim 9, wherein the steam cleaning uses a perfluorocarbon compound having a boiling point of 150 ° C or lower. The method according to claim 9 or 10, wherein the perfluorocarbon compound has a basic chemical formula C _n F _{2n + 2} (n = 6-8).