JP2000096093A - Washing pre-treating agent composition for laundry - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of removing stains, especially hibitane, which are difficult to be washed off with alkali washing agents, by using both an organic phosphonic acid-based chelating agent and an organic carboxylic acid and satisfying specific conditions. SOLUTION: This washing pre-treating agent composition for laundries contains (A) 6-60 wt.% of an organic sulfonic acid-based chelating agent (for example, 1-hydroxyethane-1,1-diphosphonic acid or ethane-1,1,2-triphosphonic acid) and (B) 5-40 wt.% of an organic polybasic carboxylic acid (preferably citric acid, malic acid or succinic acid), and has pH 3 at 25 deg.C, when converted into a 1% aqueous solution. Thereby, special stains, especially hibitane, which are difficult to be washed off with alkali washing agents, can synergistically and effectively removed in the washing processes of linen supply industry. When the washed article is then brought into contact with sodium hypochlorite, the article is not colored. It can also be expected that even the whiteness of the article darkened by repeated washing treatments, or the like, is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linen washing process, which effectively removes medical chemicals, especially stains derived from Hibiten, which are difficult to remove by ordinary washing, and whiteness of an object to be washed darkened by repeated washing. The present invention relates to a pretreatment composition for laundry effective for improvement.

[0002]

2. Description of the Related Art Generally, cleaning in the linen supply industry is performed under alkaline conditions, and has been widely used for many years because of its excellent cleaning performance against various stains. However, in the case of articles containing a large amount of chemicals such as hospital clothing, under alkaline conditions, germicidal components such as hibiten become water-insoluble substances and further contact with hypochlorite to cause coloring. Removal becomes difficult. One of the methods of cleaning hospital clothing which is difficult to remove is an acid treatment. Japanese Patent Application Laid-Open No. 58-8180 discloses a method for cleaning hospital garments, which comprises washing with an acid solution of an inorganic acid or an organic acid and then washing with a washing solution containing sodium hypochlorite. Further, Japanese Patent Application Laid-Open No. 8-218272 discloses a method for removing yellowish yellow by treating a yellowing diaper with an acidic aqueous solution containing a free carboxylic acid. However, it was difficult to completely remove the bleeding spots even by simply performing the acid treatment.

[0003]

SUMMARY OF THE INVENTION In the cleaning process of the linen supply industry, the present invention completely removes special stains, particularly hibiten, which are difficult to remove by ordinary alkali cleaning, and then contacts with sodium hypochlorite. An object of the present invention is to provide a laundry pretreatment agent for laundry that is effective in improving the whiteness of an object to be cleaned which does not form a color even when it is darkened by repeated cleaning.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned drawbacks. As a result, the present inventors have used an organic phosphonic acid-based chelating agent and an organic carboxylic acid in combination, and The present inventors have found that by performing a washing treatment with a composition having a pH of 3% or less of the aqueous solution, it is possible to effectively and effectively remove bleeding, thereby completing the present invention. That is, the pretreatment composition for laundry of the present invention,
It is characterized by containing the following components (a) and (b), and the pH of a 1% by weight aqueous solution of the composition at 25 ° C. is 3 or less. (A) Organic phosphonic acid chelating agent: 6 to 60% by weight (b) Organic polycarboxylic acid: 5 to 40% by weight

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The organic phosphonic acid chelating agent used as the component (a) in the present invention may be any one generally used as a metal sequestering agent in the field of detergents. Representative examples of the phosphonic acid chelating agents are shown below.
And specific examples thereof include 1-hydroxyethane-1,1-diphosphonic acid, ethane-1,
Examples thereof include 1,2-triphosphonic acid, ethane-1,1-diphosphonic acid, and salts thereof.

[0006]

Embedded image (In the formula, A: hydrogen or an alkyl group, alkenyl group or hydroxyl group having 1 to 6 carbon atoms B: hydrogen or an alkyl group, alkenyl group or hydroxyl group having 1 to 6 carbon atoms M: hydrogen or an alkali metal atom)

In the present invention, the amount of the component (a) is from 6 to
It is 60% by weight, preferably 10 to 30% by weight. If the amount exceeds 60% by weight, corrosion of the washing machine is caused by repeated use. If the amount is less than 6% by weight, the performance is inferior.

The organic carboxylic acid used as the component (b) in the present invention is preferably one or more polycarboxylic acids selected from citric acid, malic acid, succinic acid and gluconic acid. The compounding amount of the organic carboxylic acid as the component (b) in the present invention is 5 to 40% by weight as a composition, preferably 1%.
It is in the range of 0 to 30% by weight. (B) The amount of the component is 4
If it exceeds 0% by weight, the stability when stored at low temperature is deteriorated. If it is less than 5% by weight, desired performance cannot be obtained, which is not preferable.

[0008] The composition of the present invention is prepared by adding water to the above components (a) and (b). At that time, in order to improve the low-temperature stability of the product, a hydrotrope such as ethanol, isopropanol, ethylene glycol and polyethylene glycol can be added. further,
In the composition of the present invention, if necessary, components generally used for clothing detergents and bleaching agents, such as fragrances, pigments, fluorescent dyes and enzymes, can be blended. The cleaning pretreatment composition of the present invention has a pH of 1% by weight aqueous solution at 25 ° C. of 3 or less,
Preferably, it must be 2.5 or less. If the pH exceeds 3, the desired performance cannot be obtained.

[0009]

According to the cleaning pretreatment composition for laundry of the present invention, (a) an organic phosphonic acid-based chelating agent and (b) an organic polycarboxylic acid are used in combination, and 1% by weight.
By adjusting the pH of the aqueous solution to 3 or less, the following effects can be obtained. (1) It is possible to remove dirt which is difficult to remove by ordinary alkali cleaning, especially bleeding. (2) No color is formed by subsequent contact with sodium hypochlorite. (3) The whiteness of the object to be cleaned, which has been darkened by repeated wearing and cleaning, can be improved.

[0010]

EXAMPLES Hereinafter, the effects of the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. The percentages in each case are weight percentages unless otherwise specified.

Prior to the embodiment, an evaluation method will be described below. [How to make Hibitane-contaminated cloth] Hibiten (Zeneca Pharmaceutical Co., Ltd.)
Was diluted 10 times, and plain woven cotton cloth (# 10
0) for 5 minutes and air-dried.
%, Chelate builder 40%, and sodium carbonate 48%. After rinsing, air-dried, and cut into 5 × 5 cm, the test pieces were used in the experiment.

[Evaluation Method of Color Deformation Rate] Using five prepared Hibitane-stained cloths, the pretreatment agent composition was washed at a concentration of 1% based on the object to be washed at 50 ° C. for 10 minutes. After intermediate dehydration, nonionic surfactant 12%, chelate builder 40
% And sodium carbonate at a concentration of 1% per wash, at 60 ° C., and after rinsing, immersed in an aqueous solution of sodium hypochlorite for coloring. further,
Rinsing and drying were performed. The reflectance of the cloth surface was measured, and the coloring ratio was calculated by the following equation (1).

[0013]

(Equation 1) * The untreated cloth used was treated with sodium hypochlorite. The reflectivity is Nippon Denshoku SE200
It measured using the 0 color difference meter.

[Evaluation Method for Whiteness Improving Effect] A skin shirt darkened by repeated wearing was used as an evaluation cloth. 5cm ×
The test cloth cut to 5 cm was treated for 15 minutes with the pretreatment composition at a concentration of 1% per wash. After the intermediate dehydration, the material was washed with a detergent composition composed of 12% of a nonionic surfactant, 40% of a chelate builder, and 48% of sodium carbonate per 1% of an object to be washed, rinsed, and air-dried. This was compared with an unwashed cloth and visually evaluated according to the following criteria. ；: Whiteness improving effect is clearly recognized Δ: Whiteness improving effect is recognized to some extent ×: Whiteness improving effect is hardly recognized

Examples 1 to 8 and Comparative Examples 1 to 3 Each of the laundry pretreatment compositions shown in Tables 1 and 2 below was prepared, and its color development rate and whiteness improving effect were evaluated.
It is shown in the table.

[Table 1]Table 1: Composition and evaluation result of laundry pretreatment agent Example Composition (wt%) 1 2 3 4 5 6 7 8 Ferriox CY115 *¹20 20 20 6 30 6 10 10 Citric acid *^Two20 − − 30 6 − − 10 Malic acid *^Three− 20 10 − − 6 10 − Ethylene glycol *^Four− − − − − − − 5 − Ethanol *^Five− − − − − − − − 5 Water balance Color development rate (%) 97 96 96 95 95 90 94 93 Whiteness improvement effect ○ ○ ○ △ ○ △ ○ ○ 1% solution pH 2.0 2.0 2.1 2.3 1.9 2.4 2.3 2.3 * 1) 1-hydroxyethane-1,1-diphosphonic acid (manufactured by Lion Corporation) * 2) Manufactured by Fuso Chemical Co., Ltd. * 3) Manufactured by Fuso Chemical Co., Ltd. * 4) Mitsubishi Chemical Corporation * 5) Amakasu Chemical Industry Co., Ltd.

[0016]

TABLE 2: laundry cleaning composition and the evaluation results comparisons example composition of the pretreatment agent (wt%) 1 2 3 4 5 ferri Ox CY115 - 20 - 0.5 - phosphoric acid - - 2 - - Citric acid 20 - - 0.5- water balance color development rate (%) 78 82 75 60 41 Whiteness improving effect △ △ △ × × 1% solution pH 2.6 2.1 2.8 3.3 7.0

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Fumi Takahashi, Inventor, 1-3-7, Honjo, Sumida-ku, Tokyo F-Term in Lion Corporation (reference) 4H003 BA12 DA01 DA03 DB01 EB08 EB24 ED02 ED28 FA08 FA28

Claims (1)

[Claims] 1. A cleaning pretreatment composition for laundry comprising the following components (a) and (b) and having a 1% by weight aqueous solution at 25 ° C. having a pH of 3 or less. (A) Organic phosphonic acid chelating agent: 6 to 60% by weight (b) Organic polycarboxylic acid: 5 to 40% by weight