JP2970933B2 - Cleaning agent for dry cleaning - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cleaning agent suitable for dry cleaning.

(Prior art) 1,1,1-Trichloroethane and perchlorethylene, which are conventionally used as dry cleaning solvents, have the problem of groundwater pollution, and chlorofluorocarbon has the problem of depletion of the ozone layer. Consideration is urgent.

The present inventor previously examined the suitability for dry cleaning of 81 types of solvents (see Textile Consumption Science 27 , 8 (19
86) 352-359), none of which was suitable in all respects.

(Problems to be Solved by the Invention) Dry cleaning detergents are easy to clean, handle,
It must have appropriateness from various viewpoints such as safety.

That is, oil-soluble stains such as sebum, fat, oil smoke, etc .;
Water-soluble dirt such as sweat and water-soluble foods; "soluble" and "dispersible" for various types of dirt such as sludge, dust, etc., and cleaning dirt washed off from clothing There is little "reverse contamination" that is transferred to the clothing again, and the surface tension at which the cleaning agent penetrates into the clothing and between the stains affects the cleaning performance. In addition, the washing thing is easy to dry, the solvent life is long, distillation and recovery are easy, it does not corrode metal, it is suitable for machinery, it has low odor and it is easy to work and manage, The lack of residual odor in the washing affects the "handling". In addition, there is no deformation of the item to be washed, there is no deterioration such as yellowing of the item to be washed, it does not drop off the dye, it does not dissolve clothing accessories such as buttons, and the ignition point and flash point are high, Low toxicity affects “safety”.

Propylene glycol monomethyl ether (PM
) Is conventionally used as a cleaning agent for houses (Japanese Patent Laid-Open No. 63-2040).
0), floor cleaners (JP-A-63-112699, 168498) and ink cleaners (JP-A-2-73899),
It is not known as a cleaning agent for dry cleaning.
The present inventors have found that PM is suitable as a cleaning agent for dry cleaning from the above viewpoints, and made the present invention.

(Means for Solving the Problems) The present invention is a cleaning agent for dry cleaning containing PM, and it can be seen from various tests described below that PM has epoch-making advantages.

Test Example 1 (Solubility) Water, perchlorethylene, 1,1,1-trichloroethane, Freon 113, and PM were used as solvents. Distillation residues from a dry cleaning plant as oil-soluble stains and water-soluble stains were used as solutes. Was used as instant coffee powder. The test was performed by adding 5 ml of the solvent to 0.5 g of the solute in a test tube, and
The dissolution after standing at 72 ° C. for 72 hours was visually determined.

Table 1 shows that PM has both oil-soluble and water-soluble properties, so it is as good as oil-soluble stains as a conventional solvent and inferior to water even as water-soluble stains. It showed good solubility. In other words, in conventional chlorine-based solvents, soap is used as an auxiliary agent in order to have a dissolving performance for water-soluble stains, but PM shows good cleaning properties for water-soluble stains without using soap. Was. The surface tension of PM is 27.7, and petroleum (18-19) and Freon 113 (1
7.3), but comparable to perchlorethylene (32.3) and trichloroethane (25.6).

Test Example 2 (Reverse Contamination Property) A solvent having a low reverse contamination property has a good dry cleaning finish, can be washed even with a liquid containing a large amount of dirt, and is economical because the number of times of distillation may be small.

Reverse contamination is determined by a combination of types of dirt (solute), solvent, and clothing. Soy sauce (0.5 ml) and coffee (0.5 g) as water-soluble solutes; carbon black (0.04 g) as dispersible solute; Waste oil after long-term use of gear oil (2 g) was used as an oil-soluble solute; distillation residue from cleaning (0.04 g) was used as a miscible solute. The test was performed by placing a 2.5 × 2.5 cm piece of cloth in 75 ml of a solvent in which each solute was dissolved and stirring.
Soak for minutes. After air drying, the reflectance of each piece of cloth was measured by UV-200, and the reverse contamination rate was determined by the following equation.

Table 2 shows the results.

The following can be seen from Table 2.

Soy sauce: In a chlorine-based solvent, soy sauce breaks out and floats in a sol state. Since this sol was hydrophilic, it adhered strongly to cotton having a hydrophilic surface. It did not adhere to wool or polyester having a hydrophobic surface. On the other hand, since soy sauce was completely dissolved in water and PM, it did not show dyeing or reverse contamination.

Coffee: In chlorine solvents and PM, the solute floats as solid fine particles. These particles selectively adhered to wool with perchlorethylene and chlorofluorocarbon 113. Trichlorethane and PM did not adhere. On the other hand, the dyeing property was large in water.

Carbon black: All solvents were dispersed without being dissolved, and there was no significant difference depending on the solvent.

Waste oil: Completely dissolved with chlorine-based solvent, no reverse pollution. On the other hand, in water and PM, the oil became a sol and floated in the solution, and since this sol was lipophilic, it adhered to wool and polyester having lipophilic surfaces.

Distillation residue: a mixture of water-soluble, dispersible, and oil-soluble, and further includes a soap for charging, which is considered to be a condition close to actual dry cleaning. Reverse contamination of wool and cotton was remarkable with a chlorinated solvent, and good with water. PM was intermediate between water and chlorinated solvents.

From the above results, PM shows low reverse-staining properties to all kinds of stains and clothing, and can be evaluated as a dry cleaning detergent having excellent finish.

Test Example 3 (Shrinkage Property) The characteristic of dry cleaning is to prevent the water-absorbing fiber from swelling by washing with water and preventing the laundry from being out of shape or contracting. The shrinkage of the garment when washed in PM was tested.

In a rounder meter cup containing 10 steel balls and 100 ml of solvent, place 10 cm of cotton, hemp and wool in the center of a 12 x 12 cm piece of cloth.
Each sample cloth with a thread mark of × 10 cm was put therein, immersed at room temperature for 45 minutes, laid flat and dried, and the length between the thread marks was measured. Table 3 shows the results.

As can be seen from Table 3, the weft shrank within 2%, but it should be noted that the addition of 50% water did not cause significant shrinkage. This is due to the good hydration of PM. In the case of 1,1,1-trichloroethane and perchlorethylene, when the water in the object to be washed moves into the solvent, this water is not hydrated by the solvent and causes shrinkage of the object to be washed. Table 3 shows that no shrinkage occurs in any case.

Test Example 4 (flammability) The flash point of PM is 36 to 38 ° C, and the flammability is almost the same as that of petroleum. However, the flash point of 50% water addition
It is 62-64 ° C, and its flash point can be increased by mixing with water.

Test Example 5 (Ease of Drying) If it takes time to dry the article to be washed in the dry cleaning step, the working efficiency is significantly reduced. Test is cotton cloth 5 × 5cm
, And 0.125 g of each solvent was added dropwise, and the evaporation rate of the solvent was measured. Table 4 shows the results of comparing the evaporation rates of each solvent when perchlorethylene is set to 1.

Although the evaporation rate of PM is slow, the difference is narrowed when a washing target such as cotton cloth is involved. In addition, it is desirable that the evaporation rate is low when only the solvent is used, because the natural loss during storage of the solvent is small.

Test Example 5 (Corrosiveness) A 1 × 2 cm specimen of each of iron, aluminum and stainless steel was immersed in a solvent at room temperature for one week, then taken out and left in the air for three months to determine the degree of oxidation. No change was observed in any of the samples in PM.

(Effect of the Invention) The PM of the present invention has the following advantages as a cleaning agent for dry cleaning.

It is effective for cleaning both oil-soluble and water-soluble stains.

Low reverse pollution.

No soap is required.

Long solvent life.

There is no corrosiveness of cleaning machines.

Mixing with water is possible.

Claims (1)

(57) [Claims] 1. A dry-cleaning detergent comprising propylene glycol monomethyl ether containing 25 to 50% of water and containing no bleaching agent.