JPH0352520B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides 1, suitable for dry cleaning.
The present invention relates to a 1,1-trichloroethane composition. More specifically, the present invention relates to a 1,1,1-trichloroethane composition for dry cleaning that exhibits excellent stability against various metals in a system that is repeatedly distilled and regenerated in the presence of large amounts of water and soap. Traditionally, it has been used as a dry cleaning solvent.
Perchlorethylene is widely used as a chlorinated solvent, and mineral turpentine is widely used as a petroleum-based solvent, but these have low dissolving power for fats and oils, and even if they have excellent dissolving power, their boiling point is high and the drying temperature is high. The problem was that it became expensive and could damage clothing. On the other hand, 1,1,1-trichloroethane has excellent ability to dissolve fats and oils. It has recently been used as a dry cleaning solvent due to its low boiling point, which allows lower drying temperatures and less impact on clothing, and its low toxicity, which has less impact on the human body. It has rapidly come into the limelight. However, when using 1,1,1-trichloroethane as a dry cleaning solvent, the usage conditions are much harsher than in the case of metal degreasing and cleaning. The stability must be further increased. That is, in dry cleaning, (1) it is used in the presence of a large amount of water mixed in from clothes, stain removal, etc.; (2) It is used for a long period of time with extremely frequent distillation regeneration. (3)
Even if the loss of solvent is replenished with the initial dry cleaning solution (hereinafter referred to as new solution), the concentration of stabilizer in 1,1,1-trichloroethane will increase over the course of several hundred cleaning operations. The concentration is considerably lower than that of liquid. (Hereinafter, this will be referred to as the equilibrium concentration.) Because 1,1,1-trichloroethane for dry cleaning is used under such harsh conditions, it is important to avoid any damage to the metal equipment and metal parts that make up the dry cleaning machine. It is required to be used stably for a long period of time without corrosion. For example, 1,1,1-trichloroethane containing a large amount of soap or water generates hydrochloric acid through thermal decomposition and hydrolysis during distillation, which first causes the sparrows on the surface of the cooling coil to fall off, and then the base of the cooling coil. It corrodes copper, a metal, and produces copper rust (patina), which has a catalytic effect. Moreover, the patina is 1,1,
There is a problem in that 1-trichloroethane decomposes at an accelerated rate and eventually corrodes aluminum, iron, zinc, and SUS-304 used in other metal parts and equipment. Therefore, 1,1,1-trichloroethane for dry cleaning is extremely stable against sparrows, which are always used on the surface of cooling coils for distillation coolers in dry cleaning machines, and at the same time, it can be used as the base metal of cooling coils. aluminum, which is used in doors and sight glasses, iron, which is used as the base metal for pumps and piping, zinc, which is used inside piping, and SU, which is used in stills and tanks.
It must also be extremely stable against -304. Various types of stabilizers and combinations of stabilizers have been proposed to improve the stability of 1,1,1-trichloroethane. For example,
-4443, it is known that addition of isopropyl ether makes it stable against aluminum. Also, trioxane,
It is known that a combination of stabilizers using 1,4-dioxane is stable against various metals. However, according to metal stability evaluation using an equilibrium concentration solution obtained by repeatedly using the dry cleaning machine of the present inventor, isopropyl ether alone has no stabilizing effect on zinc, iron, and slag, and trioxane or It was found that the combination of stabilizers using 1,4-dioxane did not have a sufficient stabilizing effect on iron and carp. It has been found that if the conventional technology is simply applied to dry cleaning, the dry cleaning machine will not be able to withstand long-term use due to insufficient stability against metals. On the other hand, if a large amount of stabilizer is added in an attempt to improve metal stability, clothing accidents such as dye bleeding and yellowing due to residual stabilizer are likely to occur. Therefore, the total amount of stabilizer in the dry cleaning solvent is
It is preferably 8% by volume or less, and more preferably 7.5% by volume or less in consideration of stability. Under these constraints, the present inventor has developed a 1,1,1-trichloride for dry cleaning that exhibits excellent stability even in equilibrium concentration solutions with low stabilizer concentrations for various metals used in dry cleaning machines. As a result of repeated studies to obtain an ethane composition, it was discovered that this could be achieved using the following stabilizer system, leading to the completion of the present invention. That is, the present invention provides 1,1,1-trichloroethane with (1) isopropyl ether, (2) 1,2-
Butylene oxide, (3) nitroalkanes, (4) isobutyl alcohol, secondary butyl alcohol, 3
butyl alcohol, 2-methyl-3-butyne-
Contains at least one type of alcohol from the group of 2-ols, and the total amount of stabilizer of isopropyl ether and alcohol is 50% of the total amount of stabilizer.
95% by volume, and the amount of isopropyl ether is 25 to 95% by volume based on the total amount of isopropyl ether and alcohol stabilizer. . Examples of the nitroalkanes in the present invention include nitromethane, nitroethane, 1-nitropropane, 2-nitropropane, etc., and preferred examples are nitromethane and nitroethane. The 1,1,1-trichloroethane composition of the present invention can maintain the same metal stability in an equilibrium concentration solution as in a new solution when the stabilizer concentration decreases due to repeated use. This group includes isopropyl ether, 1,2-butylene oxide, nitroalkanes, isobutyl alcohol, secondary butyl alcohol, tertiary butyl alcohol, and 2-methyl-3-butyn-2-ol (hereinafter referred to as this group). Aluminum, zinc, copper,
It maintains an extremely excellent stabilizing effect on iron, suzmetuki, and SUS-304. However, when the composition deviates from this composition, the stabilizing effect on one of the metals is not sufficient. In addition, the total amount of stabilizers of isopropyl ether and alcohols is 50 to 95% by volume based on the total amount of stabilizers, and the amount of isopropyl ether is 25 to 95% by volume based on the total amount of stabilizers of isopropyl ether and alcohols. One day,
The synergistic effect of isopropyl ether and alcohols maintains a specific stabilizing effect on perch and iron in fresh and equilibrium concentration solutions. However, when the composition ratio of isopropyl riether and alcohol is deviated, the synergistic effect of isopropyl riether and alcohol cannot be exhibited, and the stabilizing effect against sparrow and iron is not sufficient. In carrying out the present invention, in order to fully exhibit the synergistic effect of isopropyl ether and alcohol, it is necessary to keep the total amount of stabilizers of isopropyl ether and alcohol in 1,1,1-trichloroethane stable. 50-95% by volume based on the total amount of agent,
The amount of isopropyl ether is preferably 60 to 90% by volume, and the amount of isopropyl ether is 25 to 95% by volume, preferably 35 to 90% by volume, based on the total amount of the isopropyl ether alcohol stabilizer. Hereinafter, the present invention will be explained in detail by showing Examples and Comparative Examples, but the present invention is not limited to these Examples. A. Preparation method of test solution To obtain the equilibrium concentration solution of each prescription sample, use a dry cleaning machine (Sanyo SCL-915).
Using a cotton-wool blend top and bottom work clothes and white acrylic and polyester cloth, each washer weighs approximately 10kg, then adds 300ml of 1,1,1-trichloroethane soap and repeats the standard cleaning process 500 times. carried out. The lost liquid was replenished with new liquid every 34 washers, and the sludge was taken out from the distiller every 10 washers. The equilibrium concentration solution thus obtained was used as a test solution in a metal corrosion evaluation test. B Metal Corrosion Evaluation Test (1) Aluminum scratch test Pour 50ml of the test solution into a 100ml beaker and add an aluminum alloy specimen (JIS,
H4000, A2024P) and scratch with a sharp awl twice in the lengthwise direction and twice in the perpendicular direction. Rank the post-scratch status as follows: Rank 1: No change occurs at all. Rank 2: Reaction products are observed sporadically, but this is temporary and the change stops immediately. Rank 3: Reaction products are present continuously along the wound. Rank 4: The reaction is intense and the liquid is colored. If it is ranked 2 or above in this evaluation, it can be said that there is no problem in practical use. (2) Reflux test A mixed solution of 180 ml of test liquid, 60 ml of soap, and 60 ml of distilled water was placed in a 500 ml eggplant-shaped flask equipped with a reflux condenser, and two metal plates weighed in advance were interposed between the gas and liquid phases. Raise the oil temperature to 100℃ in an oil bath and heat and reflux continuously for 72 hours. After the test, the metal plate is removed, the rust generated by hot water and acid treatment is removed, and its weight is measured.
The metal plates used in the reflux test were zinc plates (JIS, H, 4321, Aenban), copper plates (JIS, H, 3100, C1100P), iron plates (JIS, G,
3141, SPCC-B), sparrow board (JIS,
H, 3100, Suzmetsuki), SUS-304 plate (JIS, G, 4305, SUS-304). The evaluation criteria for weight loss (mg/cm ² ) in this test method are given as shown in Table 1 below.

[Table] If the evaluation is rank 2 or higher, it can be said that there is no practical problem. In addition, in the table described below, abbreviations are used for each stabilizer type. IPE = Isopropyl ether DO = 1,4-dioxane TO = Trioxane BO = 1,2-butylene oxide PrOX = Propylene oxide NM = Nitromethane NE = Nitroethane IBA = Isobutyl alcohol SBA = Secondary butyl alcohol TBA = Tertiary butyl alcohol MB = 2-Methyl-3-butyn-2-ol PrOH = propyl alcohol TAA = tertiary amyl alcohol New solutions and equilibrium concentration solutions of Examples 1 to 18 and Comparative Examples 19 to 56 are shown in Table 2. Moreover, the evaluation results of Examples 1 to 18 and Comparative Examples 19 to 56 are shown in Table 3. As is clear from the examples in Table 3, the composition of the present invention has an excellent stabilizing effect on all metals even in fresh solutions and equilibrium concentration solutions, and is stable even under the special conditions of dry cleaning. It is of extremely high industrial significance because it can be used.

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[Table] ○; Rank 1 or Rank 2
×; Rank 3 or higher

Claims (1)

[Claims] 1 1,1,1-Trichloroethane, (1) isopropyl ether, (2) 1,2-butylene oxide, (3) nitroalkanes, (4) isobutyl alcohol, secondary butyl alcohol, tertiary butyl alcohol, It contains at least one kind of alcohol from the group of 2-methyl-3-butyn-2-ol, and the total amount of stabilizer of isopropyl ether and alcohol is 50 to 95% by volume based on the total amount of stabilizer,
And the amount of isopropyl ether is 25 to 25% of the total amount of isopropyl ether and alcohol stabilizer.
A 1,1,1-trichloroethane composition for dry cleaning, characterized in that it contains 95% by volume.