WO1997000933A1

WO1997000933A1 - Bleaching composition

Info

Publication number: WO1997000933A1
Application number: PCT/JP1996/001679
Authority: WO
Inventors: Tsuneo Kobayashi; Masahito Mikami; Shuzo Nakamura; Yasuhisa Kuriyama; Jun Kokubu; Yasuo Hiro; Yoshiko Tsuji
Original assignee: Johnson Company, Ltd.
Priority date: 1995-06-23
Filing date: 1996-06-19
Publication date: 1997-01-09
Also published as: KR19990028298A; AU6136896A; ZA965236B; JP3859745B2; AR002575A1; KR100429339B1; JPH093495A

Abstract

A composition for eliminating and bleaching mould is comprised of: (A) hydrogen peroxide or a peroxide capable of generating hydrogen peroxide in its aqueous solution; and (b) a dicyanamide or its alkaline metal or ammonium salt. The pH of the mixed aqueous solution is adjusted to not lower than 7.5 with an alkaline agent or an alkaline builder.

Description

DESCRIPTION

Bleaching Composition Technical Field The present invention relates to a hydrogen peroxide-type bleaching composition excellent in its bleaching power. The bleaching composition of the present invention is suitable for use in cleaning, bleaching, sterilization, deodorization, and, particularly, elimination and bleaching of mould.

Background Art

Bleaching agents and mould-eliminating agents are classified into chlorine-type bleaching agents and hydrogen peroxide-type bleaching agents. Since the chlorine types having sodium hypochlorite as a main component are strong in bleaching power, they are used for bleaching clothes or mould growing on the walls of houses or furniture. Although the chlorine types are excellent in bleaching power, they discolor clothes and are not suitable for clothes with a colored pattern. Further, the chlorine types generate a peculiar smell based on molecular chlorine and give users an unpleasant feeling. In addition, if used in the wrong way, the chlorine types are dangerous and cause toxication. The chlorine-type bleaching agents have such drawbacks as mentioned above.

On the other hand, as compared with the chlorine types, the hydrogen peroxide types are broad in their usage area as bleaching agents and do not generate unpleasant smells, and hence, the amount of the hydrogen peroxide types used is rising, particularly, for domestic use.

However, peroxides in themselves are inferior in their bleaching power to the chlorine-type bleaching agents. Therefore, the bleaching power of the bleaching agents based on peroxides was not strong enough for bleaching clothes at low temperature, or for mould growing on the walls of houses or furniture, the walls, ceilings or tile joints of bath rooms or sinks.

Heretofore, improvement of the bleaching power of peroxides was effected by the use of peroxides such as hydrogen peroxide, an adduct of hydrogen peroxide with sodium carbonate and sodium perborate, along with N-acyl compounds such as tetraacetylethylenediamine (TAED) and tetraacetylglycoluril, or esters such as glucose pentaacetate and saccharose octaacetate. Various nitrile compounds also have been suggested as activating agents for enhancing the bleaching power of peroxides. For example, various nitriles are suggested in GB 802035; iminodiacetonitrile, in USP 3,882,035; and p-chlorobenzoyl dicyanamide, in JP-A-52-52880, while stating that those compounds are useful for bleaching activation agents. However, even when peroxides are used together with such activating agents, their bleaching power is not enough to bleach clothes or mould on houses. Furthermore, with acetylamide compounds such as TAED generally used or acetylesters such as glucose pentaacetate, there is the drawback that they will react with hydrogen peroxide to produce peracetic acid which produces a peculiar smell.

Disclosure of Invention

An object of the invention is to provide a bleaching composition which exhibits superior bleaching effects on cloths, and has superior power to bleach mould growing on the walls of houses or furniture, and also has no smell.

It has been discovered that the foregoing object can be realized by providing a bleaching composition which contains (A) hydrogen peroxide and/or a peroxide capable of generating hydrogen peroxide in its aqueous solution, and (B) a dicyanamide and/or its alkaline metal and/or ammonium salt, the pH of the mixed aqueous solution of (A) and (B) being not lower than 7.5. The present invention also provides a bleaching composition which contains (A) hydrogen peroxide and/or a peroxide capable of generating hydrogen peroxide in its aqueous solution, (B) a dicyanamide and/or its alkaline metal and/or ammonium salt and (C) an alkaline agent or an alkaline builder, the pH of the mixed aqueous solution of (A), (B) and (C) being not lower than 7.5.

The hydrogen peroxide or the hydrogen peroxide-generating peroxides used as the component (A) in the present invention include a commercially available aqueous solution of hydrogen peroxide, a sodium carbonate-hydrogen peroxide adduct in which sodium carbonate and hydrogen peroxide are added in a mole ratio of 2:3, sodium perborate hydrate and sodium perborate tetrahydrate.

The dicyanamide or the alkali metal or ammmonium salts thereof (hereinafter dicyanamide-type compound) used as the component (B) in the present invention are used in a solid or in an aqueous alkaline solution. As alkaline salts, sodium or potasium salts are preferred. As the alkaline agents or alkaline builders as the component (C), there may be used alkali metal hydroxides, aminocarboxylic acid-type builders, oxycarboxylic-type builders, phosphonic acid-type builders, high molecular weight-type builders such as acrylate-vinyl sulfonate, phosphoric acid-type builders, silicate-type builders, borate-type builders or carbonate builders, which have been known. Of these builders, silicate builders are preferred.

The bleaching composition of the present invention may be used by sprinkling on a bleaching object (A) hydrogen peroxide or a hydrogen peroxide-generating peroxide, (B) a dicyanamide-type compound and (C) an alkaline agent or an alkaline builder, individually. Further, the bleaching composition may be used along with detergent during laundry. In addition, the bleaching composition may be used by previously dissolving in water (A) hydrogen peroxide or a hydrogen peroxide-generating peroxide, (B) a dicyanamide-type compound and (C) an alkaline agent or an alkaline builder.

When using the bleaching composition of the present invention, it is preferable that it be used as a pre-mixed aqueous solution in order to easily facilitate bleaching. In such a case, the hydrogen peroxide content is 0.5 to 60 % by weight, while 0.5 to 10 % by weight is preferred, and still more preferred at 1 to 6 % by weight. When the hydrogen peroxide content is smaller than 0.5 % by weight, the bleaching power is not sufficient, however, when the hydrogen peroxide content is larger than 60 % by weight, the bleaching solution is difficult to handle. The dicyanamide-type compound content is 0.2 to 30 % by weight, while 0.5 to 10 % by weight is preferred, and still more preferred at 0.5 to 5 % by weight. Then, the alkaline agent or alkaline builder is added so that the pH of the mixed aqueous solution of (A) hydrogen peroxide and (B) cyanamide-type compound is elevated not lower than 7.5, preferably in the range of 9 to 13. When the bleaching composition is used as a composition for eliminating mould, it is preferred that it be used as a pre-mixed aqueous solution in order to easily facilitate bleaching. However, the components of the composition are prepared individually or in combination, and just before using them, they may be dissolved in water to become an aqueous bleaching solution.

The bleaching composition of the present invention may, if desired, contain known cleaning or bleaching agent components, such as surfactants, organic or inorganic builders, alkaline agents, hydrotrops, solvents, fragrances, abrasives and hydrogen peroxide- stabilizing agents. For the purpose of increasing the viscosity of the bleaching composition so that the bleaching composition does not drip when applied on a ceiling, perpendicular surface or an incline, a thickening agent may be added, which is exemplified by a synthesized or semi-synthesized polymer such as an acrylic derivative polymer and cellulose derivative, a natural polymer such as xanthan gum or bee gum, or an inorganic thickener such as alumina sol.

The following Examples and Comparative Examples are given for the purpose of illustrating the present invention and should not be construed as being limitations of the present invention.

EXAMPLES The bleaching compositions obtained in Examples and Comparative Examples were tested and evaluated as below.

1. Bleaching Test Method and Evaluation Method (1) Standard stain cloth

A stain cloth for the bleaching test EMPA #115 is used. The EMPA stain cloth is cut into pieces each being 10 cm x 10 cm and subjected to the bleaching test.

(2) Bleaching test method A bleaching composition (20 g) is put into a beaker, and the EPMA stain cloth is soaked in the bleaching composition and left standing for 10 minutes. The stain cloth is then taken out and fully rinsed with tap water. (3) Evaluation method

The test cloth treated as above is judged by visual observation and ranked into the following four categories: bleaching degree IV : almost bleached bleaching degree III: bleached a little bleaching degree II : hardly bleached bleaching degree I : not bleached at all 2. Mould Staining Elimination Test Method and Evaluation Method (1) Mould culture method

An autoclaved agar medium is put in a Petri dish. A black mould (Aureo-basidium pullulans: IFO 6353, IAM F-24) is inoculated on the medium in the Petri dish, followed by culturing at 35°C for 30 days in an incubator.

(2) A glass pipe with a given length is inserted into the agar medium on which the black mould grows. A bleaching composition is poured into the glass pipe. After standing for 30 minutes, the degree to which staining by the black mould is eliminated is then evaluated.

(3) Evaluation method The surface of the agar medium treated as above is judged by visual observation and ranked into the following four categories: elimination degree IV : almost eliminated elimination degree III: eliminated a little elimination degree II : hardly eliminated elimination degree I : not eliminated at all Examples 1 to 7 and Comparative Examples 1 to 3 A dicyanamide-type compound as shown in Table 1 was dissolved in an amount as shown in Table 1 in water, to which hydrogen peroxide was added in an amount as shown in Table 1. The pH of the resulting solution was ajusted to a value as shown in Table 1 with sodium hydroxide, thereby preparing a bleaching composition. Using the bleaching composition as prepared above, the aforementioned bleaching test and mould staining elimination test were carried out. The results obtained are as shown in Table 1.

Table 1

Example Comparative Example

Composition

1 2 3 4 5 6 7 8 9 1 2 3

Hydrogen Peroxide (wt%) 6.0 6.0 6.0 1.0 6.0 20.0 6.0 6.0 6.0 6 0 6.0

Dicyanamide (wt%) 5.0

Sodium Dicyanamide (wt%) 1.0 5.0 10.0 5.0 5.0 5.0 5.0 6.0 6.0

Ammonium Dicyanamide (wt%) 5.0 D pH Adjustor *

Ion-exchange Water (The balance to make 100 wt%) (The balance to make 100 wt%)

Total (wt%) 100 100 100 100 100 100 100 100 100 100 100 100 pH 10.4 10.5 10.5 10.3 10.0 9.5 9.5 9.5 9.5 10.5 7.0 10.5

Bleaching Test III III III III III III III III III II II I

Mould Elimination Test III III III III III III III III III II I I

* Sodium Hydroxide

Examples 10 to 18 and Comparative Examples 4 to 6 A dicyanamide-type compound as shown in Table 2 was dissolved in an amount as shown in Table 2 in water, to which hydrogen peroxide was added in an amount as shown in Table 2. The pH of the resulting solution was ajusted to a value as shown in Table 2 with sodium orthosilicate, thereby preparing a bleaching composition.

Using the bleaching composition as prepared above, the aforementioned bleaching test and mould staining elimination test were carried out. The results obtained are shown in Table 2.

Table 2

Example Comparative Example

Composition

10 11 12 13 14 15 16 17 18 4 5 6

Hydrogen Peroxide (wt%) 6.0 6.0 6.0 1.0 6.0 20.0 6.0 6.0 6.0 6.0 6.0

Dicyanamide (wt%) 5.0

Sodium Dicyanamide (wt%) 1.0 5.0 10.0 5.0 5.0 5.0 5.0 6.0 6.0

Ammonium Dicyanamide (wt%) 5.0

H pH adjustor *

Ion-exchange Water (The balance to make 100 wt%) (The balance to make 100 wt%)

Bleaching Test III IV IV III IV IV IV IV IV II II I

Mould Elimination Test III IV IV III IV IV IV IV IV II I I

* Sodium Orthosilicate

Examples 19 to 22 and Comparative Examples 7 to 9 A dicyanamide-type compound as shown in Table 3 was dissolved in an amount as shown in Table 3 in water, to which a peroxide as shown in Table 3 was added in an amount as shown in Table 3. The pH of the resulting solution was ajusted to a value as shown in

Table 3 with sodium methasilicate, thereby preparing a bleaching composition.

Using the bleaching composition as prepared above, the aforementioned bleaching test and mould staining elimination test were carried out. The results obtained are shown in Table 3.

Table 3

Example Comparative Example

Composition

19 20 21 22 7 8 9

Hydrogen Peroxide (wt%) 3.0

SPC * 3.0 6.0 3.0 6.0

PB ** 3.0 6.0

Sodium Dicyanamide (wt%) 5.0 5.0 5.0 5.0 5.0 pH adjustor ***

ω Ion-exchange Water (The balance to make 100 wt%) (The balance to make 100 wt%)

Total (wt%) 100 100 100 100 100 100 100

PH 10.3 10.5 10.3 10.5. 9.8 10.6 10.6

Bleaching Test IV IV IV IV II I II

Mould Elimination Test IV IV IV IV II I II

*: Sodium Carbonate-hydrogen Peroxide Adduct (the values indicated represent the hydrogen peroxide content. ) **: Sodium Perborate Hydrate (the values indicated represent the hydrogen peroxide content. ) ***: Sodium Metasilicate

The results as shown in Tables 1 to 3 indicate the superiority in the bleaching and mould eliminating power of the bleaching compositions which contain either hydrogen peroxide or sodium cabonate-hydrogen peroxide adduct or sodium perborate hydrate, along with a dicyanamide-type compound, the pH of the aqueous solution of the composition being adjusted to not lower than 7.5 with the alkali metal hydroxide or alkaline builder. On the other hand, when the bleaching compositions do not contain either hydrogen peroxide or sodium carbonate-hydrogen peroxide adduct or sodium perborate hydrate, or do not contain a dicyanamide-type compound, or even when the bleaching compositions contain them, if the pHs of their aqueous solution are lower than 7.5, their effects on bleaching or mould elimination are circumscribed or may have no effect at all.

As for the alkaline agent used as a pH control agent, the alkaline builders as shown in Tables 2 and 3 are superior to the alkali metal hydroxides as shown in Table 1 in the effects on bleaching and mould elimination. Therefore, it is preferred that the alkaline builders should be used as alkaline agents.

Claims

1. A bleaching composition which contains (A) hydrogen peroxide and/or a peroxide capable of generating hydrogen peroxide in its aqueous solution, and (B) a dicyanamide and/or its alkaline metal and/or ammonium salt, the pH of the mixed aqueous solution of

(A) and (B) being not lower than 7.5.

2. A bleaching composition according to Claim 1, wherein (A) the hydrogen peroxide or the hydrogen peroxide-generating peroxide converted to hydrogen peroxide is contained in an amount of 0.5 to 60 % by weight, and (B) the dicyanamide or its alkaline metal or ammonium is contained in an amount of 0.2 to 30 % by weight.

3. A bleaching composition which contains (A) hydrogen peroxide and/or a peroxide capable of generating hydrogen peroxide in its aqueous solution, and (B) a dicyanamide and/or its alkaline metal and/or ammonium salt and (C) an alkaline agent or an alkaline builder, the pH of the mixed aqueous solution of (A),

(B) and (C) being not lower than 7.5.