JPH0741797A - Cleaning liquid composition - Google Patents

Abstract

(57) [Summary] [Object] To provide a cleaning liquid composition having a good cleaning effect, a flash point, a low odor, a low toxicity, and an excellent safety. A cleaning liquid composition comprising 70 to 85 parts by weight of N-methyl-2-pyrrolidone and 30 to 15 parts by weight of water.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a cleaning liquid composition,
More specifically, the present invention relates to a cleaning liquid composition suitable for cleaning oils, polymers, scales, soldering fluxes, metal soaps and the like attached to the surface of metals or resins.

[0002]

2. Description of the Related Art Conventionally, hydrocarbon solvents such as aromatic and aliphatic solvents, terpene solvents and alcohol solvents have been used for washing the above oils and the like. There are safety problems such as a relatively low flash point and toxicity.

Freon-based solvents and chlorine-based solvents are also used, but these solvents are planned to be prohibited from production in the near future as substances that destroy the ozone layer. Furthermore, chlorine-based solvents are not toxic. It is strong and its regulations are strict to prevent water pollution.

Aqueous detergents, aqueous solutions of phosphates, etc.
Wastewater treatment equipment requires a large space and is not preferable from the economical aspect.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a cleaning liquid composition having a good cleaning effect and excellent safety.

[0006]

The present inventors have made various studies in order to solve the above-mentioned drawbacks of various cleaning solutions and to find a cleaning solution having a good cleaning effect. As a result, they have found that a cleaning solution composition containing N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP) and water in a specific mixing ratio can effectively achieve the above-mentioned problems. .

That is, the cleaning liquid composition of the present invention has a good cleaning effect, has no flash point, has a low odor, is less toxic, and is very excellent in terms of safety. Further, in the cleaning liquid composition of the present invention, even if the rinsing step is simplified, no scale remains on the surface of the resin product and the waste water treatment is easy, as compared with other aqueous solution-based cleaning agents. NMP has a high boiling point, has a small loss due to evaporation, and can be reused by distillation, and is also excellent in economical efficiency.

The present invention provides N-methyl-2-pyrrolidone 7
A cleaning liquid composition containing 0 to 85 parts by weight and 30 to 15 parts by weight of water.

In the cleaning liquid composition of the present invention, the mixing ratio of NMP and water is 70 to 85 parts by weight of NMP and 3 parts of water.
0 to 15 parts by weight, preferably 25 to 15 parts by weight of water with respect to 75 to 85 parts by weight of NMP, and particularly preferably 20 to 15 parts by weight of water with respect to 80 to 85 parts by weight of NMP. If the NMP content is less than 70 parts by weight and the water content exceeds 30 parts by weight, the cleaning effect is significantly decreased, and the cleaning effect due to heating is not sufficiently increased. If the NMP content exceeds 85 parts by weight and the water content is less than 15 parts by weight, the flash point of NMP cannot be extinguished, which is not preferable in terms of safety.

Further, the cleaning liquid composition of the present invention may contain conventional additives such as a surfactant, an antioxidant, an ultraviolet absorber and an anticorrosive agent as long as the object of the invention is not impaired. Here, the surfactant as an optional substance is used for improving permeability and dissolution rate into oils, polymers, scales, soldering flux, metal soap and the like. The surfactant is preferably a nonionic surfactant, for example, higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, higher alkylamine ethylene oxide adduct, sorbitol and sorbitan fatty acid ester, Any of sucrose fatty acid ester, silicon type, fluorine type and the like can be used. Further, other optional substances such as UV absorbers and antioxidants help improve stability for long-term storage of liquids, and as the UV absorbers, for example, benzotriazole-based, benzophenone-based, hindered amine-based, etc. can be used. As the antioxidant, for example, any of those that are soluble in the cleaning liquid composition of the present invention, such as phenol-based, amine-based, sulfur-based, phosphorus-based, and the like can be used.

The method for producing the cleaning liquid composition of the present invention is not particularly limited, and generally known means can be adopted.

The washing method itself with the washing liquid composition of the present invention is not particularly limited, and any known method can be used.
For example, it is preferable to carry out by wiping with a sponge impregnated with the cleaning liquid composition, dipping in the cleaning liquid composition and / or spraying. In the cleaning by immersion, it is more preferable to combine stirring, shaking, ultrasonic waves, air bubbling and the like at the same time in order to enhance the cleaning effect. In this case, it is preferable that the ultrasonic wave is used under an oscillation frequency of 20 to 100 kHz and an oscillation output of 10 to 200 W / l. In air bubbling, fine air bubbles are preferably aerated at a gas: liquid volume ratio of about 1: 1 to 5: 1 to raise insoluble dirt in the cleaning liquid composition together with the air bubbles and also separate insoluble dirt. can do.
In cleaning by spraying, the pressure is, for example, 0.
5 to 10 kg / cm ² G is preferable. In any case, the cleaning time is preferably 0.5 to 20 minutes, particularly preferably 1 to 5 minutes. If the time is less than 0.5 minutes, the cleaning is insufficient and the adhered dirt cannot be removed sufficiently, while if the time is more than 20 minutes, the cleaning effect is not particularly improved. The washing temperature is preferably 30 to 80 ° C. Particularly preferably 50 to 65
C., and the cleaning effect can be remarkably increased by treating at a high temperature. If the temperature is lower than 30 ° C., the cleaning becomes insufficient, and if the temperature exceeds 80 ° C., the evaporation rate of water is large and the control of the water concentration of the cleaning liquid composition becomes complicated, which is not preferable.

The cleaning liquid composition of the present invention is widely suitable for cleaning oils and the like adhering to the surface of metals, resins and the like. For example, a polyolefin resin for automobile bumpers described in Japanese Patent Application No. 5-111195. Product cleaning, paint / coating resin peeling, metal surface rust / oil / dirt removal, molding die cleaning, solder flux removal, electronic / precision equipment cleaning, printing equipment cleaning, polymerization equipment cleaning Used for etc.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[0015]

【Example】

[0016]

Example 1 An open-type flash point was measured using a cleaning liquid composition prepared by mixing 15.0 g of distilled water with 85.0 g of NMP. A Cleveland flash point tester was used as an apparatus, and the test was carried out in accordance with JIS K2274. When I tried to measure the flash point by gradually increasing the sample temperature, a small flame disappeared due to steam at a temperature of 126 ° C or higher,
Flash point measurement was not possible. Therefore, the cleaning liquid composition does not have a flash point and does not correspond to a dangerous substance specified by the Fire Service Law.

[0017]

Comparative Example 1 The flash point was measured under the same conditions as in Example 1 except that a cleaning liquid composition prepared by mixing 89.0 g of NMP with 11.0 g of distilled water was used as a sample. As a result, the cleaning liquid composition was found to catch fire at 122 ° C.

As described above, the cleaning liquid composition of the present invention is
Highly safe with no flash point.

[0019]

Examples 2 to 4 and Comparative Example 2 NMP was mixed with distilled water to obtain NMP concentrations of 85% by weight, 80% by weight and 70% by weight.
(Each of Examples 2 to 4) and 50% by weight (Comparative Example 2) of each cleaning liquid composition were prepared and used as samples for the following tests.

K in accordance with ASTM D1133-90
The B value was measured. Also, ASTM D1133-9
Although 0 does not show the measuring method for the heated liquid, the KB value at each temperature was obtained by keeping the sample liquid and the Kauri gum-butanol solution at each measuring temperature. The result is shown in FIG.

[0021]

FIG. 1 shows that the KB value largely depends on the NMP concentration, and that the difference in the KB value depending on the NMP concentration tends to increase particularly during heating.

From the above, it is clear that the cleaning liquid composition of the present invention has a higher dissolving power than that of Comparative Example 2.

[0023]

Example 5 A 5 cm × 5 cm 200-mesh stainless steel wire net was dipped in a water-soluble cutting oil (Yushiroken EC50, trademark, made by Yushiro Kagaku Co., Ltd.), then pulled up and left at room temperature for 2 hours. The amount of oil attached to the wire net after standing was 97.2 mg. The wire mesh to which the cutting oil adhered was dipped in 100 ml of an 85 wt% NMP aqueous solution, and washed with an ultrasonic cleaner (oscillation frequency 28 kHz, oscillation output 80 W / l) at room temperature for 10 seconds. After washing, it was dried at 90 ° C. for 1 hour, allowed to cool at room temperature for 30 minutes, and then weighed. When the removal rate of the cutting oil by washing was determined, the oil was removed by 99% by weight.

[0024]

Example 6 Except that a 75 wt% NMP aqueous solution was used,
A cleaning test was performed under the same conditions as in Example 5. The amount of oil attached to the wire mesh before washing was 84.0 mg, and the oil removal rate by washing was 94% by weight.

[0025]

Comparative Example 3 Except that a 50 wt% NMP aqueous solution was used,
A cleaning test was performed under the same conditions as in Example 5. The amount of oil attached to the wire mesh before washing was 81.0 mg, and the oil removal rate by washing was 87% by weight.

Examples 5 and 6 and Comparative Example 3 are NMP, respectively.
The removal rates of oil by washing at room temperature were measured with the aqueous solution concentrations of 85, 75 and 50% by weight. The cleaning liquid compositions of the Examples were superior in oil removal rate as compared with the Comparative Examples.

[0027]

EFFECT OF THE INVENTION The cleaning liquid composition of the present invention has a good cleaning effect, has no flash point, has a low odor, is less toxic and has excellent safety. Therefore, it is industrially extremely useful as a substitute for the conventional cleaning liquid.

[Brief description of drawings]

FIG. 1 shows that the concentration of an NMP aqueous solution is 85% by weight,
It is the graph which showed the change with temperature of the KB value of each cleaning liquid composition which is 0 weight%, 70 weight%, and 50 weight%.

Claims (1)

[Claims] 1. N-Methyl-2-pyrrolidone 70-85
A cleaning liquid composition comprising 30 parts by weight of water and 30 to 15 parts by weight of water.