JP3059222B2 - Hypochlorite bleaching composition - Google Patents

Abstract

Liquid aqueous bleaching compositions are disclosed which comprise a pH buffering means with low sensitivity to water hardness and an alkali metal hypochlorite. A method of treating fabrics with said compositions is also disclosed.

Description

Description: TECHNICAL FIELD The present invention relates to liquid bleaching compositions which are suitable for laundry applications, including manual laundry as well as laundry using automatic washing machines.

BACKGROUND OF THE INVENTION Liquid bleaching compositions are well known in the art. Among the various bleaching compositions available, bleaching compositions that rely on bleaching with hypochlorite are often preferred, primarily for performance reasons, especially at lower temperatures.

However, there are some limitations on the suitability of hypochlorite bleach. In particular, it is well known to consumers that a disadvantage associated with the use of hypochlorite based compositions is to damage and / or yellow the fabric being bleached.

Accordingly, it is an object of the present invention to provide a hypochlorite-containing composition which improves the whiteness of the fabric and is suitable for use in laundry applications.

Another object of the present invention is to provide a hypochlorite-containing composition suitable for use in laundry applications wherein the safety of the fabric is improved.

PH buffering means having low sensitivity to water hardness, with alkali metal hypochlorites or mixtures thereof,
That is, when used in a 1 M solution of pH 10, the pH buffering means requires more than 2.5 mM calcium ions to precipitate the calcium salt of the alkali anion of the pH buffering means at 25 ° C. The present inventors have found that the above object can be satisfied by formulating such an alkaline liquid composition. Said composition is compared to the same composition without said pH buffering means which has a low sensitivity to water hardness according to the invention,
The whiteness of the fabric and / or the safety of the fabric can be improved for the treated fabric. Also, the present invention comprises the above-mentioned pH buffering means, wherein the liquid hypochlorite bleach-containing composition has low sensitivity to water hardness, together with a precipitant such as carbonate and / or silicate. The present inventors have found that in a preferred embodiment, outstanding whiteness and / or fabric safety performance is obtained. In fact, in a hypochlorite bleaching composition, the use of a pH buffering means having a low sensitivity to water hardness together with a precipitant, such as carbonate and / or silicate, results in a whiteness of the fabric. It has been found that praise has an effect on the performance of the fabric and / or the safety of the fabric.

One advantage of the compositions of the present invention is that they decontaminate various types of stains, including bleachable stains (eg, coffee), enzyme stains (eg, blood), and grease stains (eg, lipstick). It is the composition of the present invention that can provide significant fabric whitening action and / or fabric safety properties without compromising performance.

Another advantage of the composition of the present invention is that the bleaching composition can be made from natural fabrics (eg, cotton, viscose, linen, silk, and wool), synthetic fabrics, for example, fabrics made from polymer fibers of synthetic origin. And for bleaching various types of fabrics, including fabrics made from both natural and synthetic fibers. In fact, the compositions of the present invention are based on the use of commercially available hypochlorite bleach and the use of hypochlorite bleach on synthetic fibers, as evidenced by precautions on garment labels. It can be used on synthetic fibers, despite the preconceptions customarily established for

Yet another advantage is that it has low sensitivity to water hardness
A liquid composition according to the invention comprising a pH buffering means,
The bleaching buffering action can be extended without increasing the pH of the composition itself as compared to the same composition without the pH buffering means, i.e., from the moment the dilution is completed, The ability to keep the pH of the bleaching solution as high as possible during the bleaching cycle.

Compositions comprising hypochlorite and a pH buffering means have been described in the art.

WO 88/05462 discloses trisodium phosphate, sodium hydroxide, sodium hypochlorite and a pH of about 10 to
A buffer to maintain at 12, for example, sodium carbonate,
Disclosed is a composition for removing stains from fabrics, comprising an aqueous solution of sodium bicarbonate, sodium sesquicarbonate, or a mixture thereof. In addition, WO 88/05462
It states that the buffer system used should bring the pH as close to pH 10 as possible, consistent with effective decontamination to provide a product that is more gentle on skin and fabric than at higher pH. Is disclosed as being preferred. WO 88/05462 also discloses a method for removing stains from fabrics with the composition. However, no pH buffering means with low sensitivity to water hardness as described herein is described anywhere in WO 88/05462.

EP-A-622,451 describes hypochlorite, sodium hydroxide, bleach-stable perfume, and buffering the pH of the diluted composition to a constant value through use. Compositions suitable for use in diluted form comprising carbonates and / or silicates as systems are disclosed. European Patent Application (EP-A) No. 62
No. 2,451 also discloses a bleaching method in which such a composition is contacted with a fabric. No pH buffering means having low sensitivity to water hardness is disclosed.

European Patent Application (EP-A) 653,482 and European Patent Application (EP-A) 668,345 disclose strong alkaline sources, pH buffering means and optionally other types of components,
For example, compositions containing hypochlorite, each comprising a radical scavenger and a polycarboxylate acid of pyridine, are disclosed. The pH buffering means disclosed therein are alkali metal silicates and / or carbonates, sodium borate and sodium sesquicarbonate. No pH buffering means having a low sensitivity to water hardness is disclosed anywhere in said patent application.

In British Patent 1,282,906, as a stabilizer,
A stabilized aqueous alkali metal hypochlorite solution comprising an alkali metal heptanoate or boroheptanoate is disclosed. "Alkali metal boroheptanoate" as used in GB 1,282,906 refers to a mixture of an alkali metal heptanoate and boric acid or an alkali metal metaborate, wherein the mixture is Generally contains 2 grams moles of alkali metal heptanoate per gram atom of boron in boric acid or metaborate. However, no strong alkaline source or solution pH is disclosed. Also,
No laundry use is disclosed.

Belgian Patent (BE) 749,728 describes N-
A hydride, a hypohalite, such as hypobromite, hypochlorite or hypoiodite, in equilibrium with the corresponding N-halogenated compound; An aqueous system comprising a buffered system to maintain the range and stabilize the system prior to use is disclosed. The buffering systems described therein generally include acetates, carbonates, phosphates, polyphosphates, organophosphates, borates, polyborates, organic borates, silicates, It is a polysilicate, an organosilicate or a mixture thereof. Strong alkalinity sources, such as sodium hydroxide / potassium hydroxide, are also disclosed. These bleaching compositions are particularly suitable for bleaching fibrous materials. However, the Belgian patent (B
E) No. 749,728 discloses a pH buffering means which is sensitive to water hardness, such as silicates or carbonates, which have a low sensitivity to water hardness, as described in the present invention. No distinction is made between pH buffering means.

U.S. Pat. No. 4,000,082 discloses a defoaming composition based on lithium salts. More specifically, U.S. Pat. No. 4,000,082 discloses an anionic surfactant, a nonionic surfactant, and 5 to 50% by weight of the total composition.
Aqueous solution comprising a highly alkaline compound selected from sodium hydroxide, sodium carbonate, sodium bicarbonate, sodium metaborate and the like, and from 1 to 5% by weight of a lithium salt including lithium hypochlorite A cleaning composition is disclosed. Needless to say, the use of laundry bleaching is not disclosed.

In practice, an alkaline liquid bleaching composition comprising hypochlorite, for bleaching fabric, has a pH of 1M.
When used in solution, to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C. 2.
Benefits derived from using the pH buffering means according to the invention, requiring more than 5 mM calcium ions,
That is, the improved fabric whiteness and / or fabric safety for fabrics treated therewith has not been recognized in the prior art.

DISCLOSURE OF THE INVENTION The present invention encompasses a liquid bleaching composition having a pH of 8 to 14, wherein the composition comprises an alkali metal hypochlorite, or a mixture thereof, and a pH buffering means. And said
pH buffering means, when used in a 1 M solution at pH 10, 25 ° C
Requires more than 2.5 mM calcium ions to precipitate the calcium salt of the alkali anion of the pH buffering means, provided that when the pH buffering means is sodium metaborate, the alkali metal hypochlorite The salt is not lithium hypochlorite.

A method for bleaching a fabric, which improves the whiteness of the fabric and / or the safety of the fabric, comprises the step of contacting the fabric with a liquid bleaching composition having a pH of 8 to 14, wherein the composition comprises an alkali metal hypochlorite. Or a mixture thereof, and a pH buffering means, wherein the pH buffering means comprises 1M at pH 10.
When used in solution, more than 2.5 mM calcium ions are required to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C.

BEST MODE FOR CARRYING OUT THE INVENTION The composition of the present invention is a liquid bleaching composition. Thus, as a first essential component, the composition of the present invention comprises hypochlorite. Various types of alkali metal hypochlorites are commercially available, and it is preferred to use sodium hypochlorite in the present invention,
This is not critical to the present invention. The composition according to the invention comprises a bleaching amount of an alkali metal hypochlorite, or a mixture thereof, which amount is typically
Represents 0.1 to 20% by weight of the total composition of said alkali metal hypochlorite, based on active chlorine. Preferred compositions according to the invention comprise from 0.5 to 8% by weight, based on active chlorine.
Comprising an alkali metal hypochlorite, or a mixture thereof.

As a second essential component, the composition according to the invention is a pH buffering means or a mixture thereof having a low sensitivity to water hardness, i.e. when used in a 1 M solution at pH 10, the pH buffer at 25 ° C. 2.5 mmol (m 2) to precipitate the calcium salt of the alkali anion of the
M) more, preferably more than 3.5 mM, more preferably
PH buffering means requiring greater than 5 mM of said calcium ions.

Therefore, a suitable pH for use in the present invention
The buffering means is selected by assessing the amount of Ca ions required to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C. when used in a 1 M solution at pH 10. This required amount of Ca ions can be determined using the method reported hereinafter in the experimental data.

Suitable pH buffering means having a low sensitivity to water hardness preferably have a buffering pH of 8.5 to 13, more preferably 9 to 11, ie the pKa of their conjugate acid.

Examples of said pH buffering means having low sensitivity to water hardness include alkali metal salts of metaborate and stannate and mixtures thereof. Alkali metal salts of metaborates, such as sodium and potassium metaborate, or mixtures thereof, are particularly preferred in the present invention.

The composition according to the invention comprises from 0.01 to 20% by weight of the total composition,
Preferably 0.1 to 15% by weight, more preferably 0.5 to 8% by weight of said pH buffering means, said pH buffering means when used in a 1 M solution at pH 10 at 25 ° C.
More than 2.5 mM calcium ions are required to precipitate the calcium salt of the alkaline anion of the pH buffering means.

This time, when used in a 1 M solution at pH 10, the pH buffering means requiring more than 2.5 mM calcium ions to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C. When added to a liquid composition containing chlorate, the buffering action through complete bleaching can be prolonged, i.e. the same composition without the pH buffering means, or of the pH buffering means. Alternatively, from the moment the dilution is complete, compared to the buffering effect obtained using the same composition but containing other components that act as pH buffering means, for example, carbonates and / or silicates It has been found that the pH of the bleaching solution can be kept as high as possible for a long period of time.

The buffering action of the pH buffering means is that hypochlorite is
Reduces the conversion to hypochlorous acid, one of the species responsible for fabric damage and / or fabric whiteness, thereby improving fabric safety and / or fabric whiteness. It has been found possible.

"Improvement of the whiteness of the fabric" means that, in the present invention, the whiteness of the fabric achieved by using the hypochlorite composition of the present invention is the same as that of the same composition without the pH buffering means. Or using the same composition but containing other components acting as pH buffering means in place of the pH buffering means according to the invention, for example carbonates and / or silicates It means that the whiteness is improved as compared with the obtained whiteness.

"Improvement of fabric safety" means that in the present invention, the damage of the fabric caused by using the hypochlorite composition of the present invention is the same composition without the pH buffering means. Use or the pH according to the invention
To reduce the damage as compared to damage caused using the same composition but containing other components, such as carbonates and / or silicates, that act as pH buffering means instead of buffering means. means.

The safety of the fabric is determined by the copper number test
Can be evaluated by various test methods including:
In fact, the number of copper on the fabric is proportional to the amount of aldehyde groups derived from the oxidation of the cellulose and, therefore, to the damage of the fabric. Thus, the higher the copper number, the more damage to the fabric. The copper number test consists in measuring the number of grams of copper reduced from cupric to cuprous by 100 g of cellulose. To do this, an excess of a solution of copper sulphate is added and the following reaction is carried out.

[Aldehyde group] from fabric + Cu ⁺⁺ → Cu ₂ O (cuprous oxide) Fe ⁺⁺ ions are then added to form ferrous sulfate in exactly the same amount as the cuprous oxide present.

Fe ₂ (SO ₄ ) ₃ + Cu ₂ O + H ₂ SO ₄ → 2FeSO ₄ + H ₂ SO ₄ + 2CuSO ₄ Finally, 0.1N which oxidizes Fe ⁺⁺ (ferrous) ions to Fe ⁺⁺⁺ (ferric) ions The ferrous sulfate is measured by titration with potassium permanganate.

The safety of the fabric can also be evaluated by a tensile strength loss test. This method consists in measuring the tensile strength of the cloth by pulling the cloth until a predetermined cloth breaks. The force required to break the fabric (expressed in kg) is the "ultimate tensile strength" and can be measured with a "stress-strain Instron tensile tester". The lower the force required to break the fabric, the less damage the fabric will cause on the fabric.

One advantage of the present invention is that the buffering of the hypochlorite composition of the present invention reduces hand strain.

As a third essential feature, the composition according to the invention has a composition of 8 to
14, preferably 9-13.5, more preferably 9.5-13.5 p
Has H. It is in this alkaline range that the optimum stability and performance of hypochlorite is obtained.

Thus, the compositions of the present invention comprise a strong alkalinity source. Preferred compositions according to the invention comprise up to 10% by weight of the total composition, preferably 0.04 to 5%, more preferably 0.1 to 2% by weight of said strong alkaline source, or a mixture thereof. Examples of strong alkaline sources are hydroxides of alkali metals, for example potassium hydroxide and / or sodium hydroxide, or alkali metal oxides, for example sodium oxide and / or potassium oxide.

The compositions of the present invention are aqueous. Thus, the compositions of the present invention preferably comprise 60-98%, more preferably 80-97%, most preferably 85% by weight of the total aqueous liquid bleaching composition.
It comprises water in an amount of ~ 97% by weight.

The composition according to the invention further comprises, as an optional but preferred component, a precipitant. Carbonates, polycarbonates, sesquicarbonates, silicates, alkali metal salts of polysilicates or mixtures thereof are particularly useful for use in the present invention. Preferred alkali metal salts for use in the present invention are the sodium and potassium salts. Particularly preferred precipitants are the alkali metal salts of silicates and / or carbonates. Preferred alkali metal salts of silicates and / or carbonates are sodium silicate and sodium carbonate (both of which are commercially available), or mixtures thereof.

The composition according to the invention comprises up to 5% by weight of the total composition, preferably 0.01 to 4% by weight, more preferably 0.02 to 3% by weight.

The precipitant, for example, sodium carbonate and / or sodium silicate, comprises hypochlorite and a pH buffering means, wherein the pH buffering means when used in a 1 M solution at pH 10 2.5 mM to precipitate the calcium salt of the alkali anion of the pH buffering means at 25 ° C.
When added into an alkaline liquid composition, which requires more calcium ions, it further acts on the top of one of the pH buffering means, thereby increasing the whiteness and the whiteness of the fabric treated with the composition. It is presumed that safety can be further improved. In fact, the precipitants can reduce or even eliminate impurities in the composition as such, and especially in a bleaching environment. The impurities include calcium, magnesium and heavy metal ions such as Cu, Fe, Ni, Co, and others, which have been found not to adversely affect both the whiteness of the fabric and the safety of the fabric. .

In fact, it is believed that in a bleaching / laundering environment, metal ions catalyze hypochlorite attack on the fabric, generating yellow oxidized species. Further, it is presumed that the metal ions are adsorbed on the oxidized fabric as a colored species themselves and catalyze the decomposition of the brightener adsorbed on the fabric. The metal ions also stabilize enzymatic contamination, for example, blood and grass coloring pigments. Metal ions also catalyze the depolymerization of cotton fibers, leading to a decrease in the tensile strength of the fabric, thereby reducing the resistance of the fabric.

The precipitant according to the invention also acts as a pH buffering means, whereby the pH buffering action of the pH buffering means according to the invention can be completed.

The composition according to the invention may furthermore comprise other optional ingredients, such as bleach-stable surfactants, organic or inorganic alkalis, pigments, dyes, optical brighteners, solvents, chelating agents, radical scavengers and Others can be included.

The compositions according to the invention are used in laundry applications, preferably in diluted form. The expression "used in diluted form" in the present invention encompasses dilution by the user, for example in hand washing applications, as well as dilution by other means, for example in a washing machine.
The preferred dilution level is 0.2 for manual laundry applications.
1-20%, and 0.1-10% in the washing machine.

The present invention further includes a method of bleaching a fabric comprising the step of contacting the fabric with a liquid bleaching composition having a pH of 8 to 14, wherein the composition comprises an alkali metal hypochlorite, or a mixture thereof. , A pH buffering means,
The pH buffering means, when used in a 1 M solution at pH 10,
At 25 ° C., more than 2.5 mM calcium ions are required to precipitate the calcium salt of the alkaline anion of the pH buffering means. In a preferred embodiment, the composition used in the method for bleaching a fabric further comprises a precipitant as defined above. The method according to the invention improves the whiteness of the fabric and / or the safety of the fabric.

More specifically, the method for bleaching a fabric according to the present invention comprises first contacting the fabric with a liquid bleaching composition having a pH of 8 to 14, wherein the composition is an alkali metal hypochlorite,
Or a mixture thereof, and a pH buffering means, wherein the pH buffering means, when used in a 1 M solution at pH 10, precipitates the calcium salt of the alkali anion of the pH buffering means at 25 ° C. Requires more than 2.5 mM calcium ions, and then for a period sufficient to bleach the fabric, typically 1 to 60 minutes, preferably 5 to 5 minutes.
Leaving the fabric in contact with the bleaching composition for 3030 minutes, and then rinsing the fabric in water to remove the bleaching composition. When the fabric is to be washed, i.e. when washed with a conventional composition comprising at least one surfactant, by contacting the fabric simultaneously with the bleaching composition and the detergent composition according to the invention. The bleaching and washing of the fabric can be performed together, or the washing can be performed before or after bleaching the fabric. Thus, the method according to the invention enables the bleaching of the fabric and, if necessary,
A rinsing step prior to the step of contacting the fabric with the bleaching composition and / or in the step of contacting the fabric item with the bleaching composition, and / or when the bleaching composition is removed from the fabric; Followed by at least one
It is possible to wash a fabric with a detergent composition comprising a type of surfactant.

It is preferable to perform the bleaching method of the present invention before washing the fabric. In fact, bleaching the fabric with the composition according to the invention before washing it with a detergent composition, with less energy, better whiteness and stain with less energy than washing the fabric first and then bleaching. It was observed that removal was provided.

When used in a 1 M solution of alkali metal hypochlorite and pH 10, more than 2.5 mM calcium ions are required at 25 ° C. to precipitate the calcium salt of the alkali anion of the pH buffering means. pH buffering means,
The alkaline liquid composition according to the present invention, comprising a strong alkaline source for obtaining a desired pH and, if necessary, a precipitant, can be produced by a method comprising the following steps.

-Mixing the alkali metal hypochlorite, the strong alkaline source and water;-adding the pH buffering means and, if necessary, the precipitant;-separating the precipitate formed from the composition. I do.

“Separating the formed precipitate” means, in the present invention,
It means that known means can be used to remove the solid phase from the liquid phase. Thus, the precipitate formed can be removed from the composition of the invention by sedimentation and / or filtration and / or centrifugation.

Experimental data Sensitivity to water hardness was determined by the following test method.

A 1M solution of the buffer to be investigated was prepared, 100 g of each solution were weighed, the pH was reduced to 10, and any precipitate that had formed was filtered off of the solution. Then, to each of the 1M solutions in the buffer means, a preservation solution of calcium chloride (0.05 M) was added at the stage of 0.5 ml. After stirring for 20 minutes, the turbidity was measured by spectroscopy at 360 nm against a reference prepared from a pure solution. When a precipitate formed, the experiment was stopped and the amount of calcium added was recorded.

 The following results were obtained.

EXAMPLES The following compositions, which further illustrate the invention, were prepared by mixing the indicated ingredients in the indicated proportions.

All of the above compositions have improved safety for fabrics when treating the fabric without compromising the ability to decontaminate a wide variety of stains, such as bleachable stains, enzyme stains and grease stains. And / or improved whiteness.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Giuseppe, Trigiante, California, United States, Stanford, Campus, Drive, 704, Rains, House, Apartment, 23E (56) References JP 50-70411 (JP, A) JP-A-54-114485 (JP, A) JP-A-3-166299 (JP, A) US Patent No. 2097517 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) ) C11D 7/54 C11D 3/395

Claims (17)

(57) [Claims] 1. A liquid bleach having a pH of 8 to 14, comprising hypochlorite of an alkali metal or a mixture thereof, and pH buffering means having low sensitivity to water hardness. The sensitivity is defined by assessing the calcium ion requirement, i.e., when used in a 1 M solution at pH 10, 2.5 mM to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C. A liquid bleaching composition requiring more calcium ions, wherein the alkali metal hypochlorite is not lithium hypochlorite when the pH buffering means is sodium metaborate. 2. A liquid bleaching composition having a pH of 8 to 14, comprising hypochlorite of an alkali metal, or a mixture thereof, and a pH buffering means having low sensitivity to water hardness. Contacting the fabric, wherein the sensitivity is defined by assessing the calcium ion requirement, i.e., when used in a 1 M solution at pH 10, the calcium salt of the alkali anion of the pH buffering means at 25 ° C. A method for improving fabric whiteness and / or fabric safety, comprising the step of precipitating requiring more than 2.5 mM calcium ions. 3. After the step of contacting the fabric with the bleaching composition, the following step: leaving the fabric in contact with the bleaching composition for a period sufficient to bleach the fabric. 3. The method of bleaching a fabric according to claim 2, further comprising: rinsing the fabric with water to remove the bleaching composition. 4. When the bleaching composition is removed before the step of contacting the fabric with the bleaching composition and / or in the step of contacting the fabric with the bleaching composition and / or after the rinsing step. Washing the fabric with a detergent composition comprising at least one surfactant,
The method of claim 3. 5. The method according to claim 2, wherein the bleaching composition is brought into contact with the fabric in a diluted form. 6. The process according to claim 2, wherein the composition comprises from 0.1 to 20% by weight of the total composition of hypochlorite, based on active chlorine. . 7. A pH having a low sensitivity to water hardness.
Wherein the buffering means, when used in a 1 M solution at pH 10, requires more than 3.5 mM calcium ions to precipitate the calcium salt of the alkaline anion of the pH buffering means at 25 ° C. Item 7. The method according to any one of Items 2 to 6. 8. The method according to claim 2, wherein the pH buffering means is an alkali metal salt of metaborate or stannate or a mixture thereof. 9. The composition according to claim 1, wherein the composition comprises 0.01 to 20% by weight of the total composition
9. The method according to any one of claims 2 to 8, comprising the pH buffering means. 10. The composition, comprising up to 5% by weight of the total composition of a precipitant, wherein the precipitant comprises a carbonate,
The method according to any one of claims 2 to 9, which is a polycarbonate, sesquicarbonate, silicate, alkali metal salt of polysilicate, or a mixture thereof. 11. The method according to claim 2, wherein the pH of the composition is 9-13.5. 12. The composition according to claim 1, comprising from 0.1 to 20% by weight of the total composition of hypochlorite, based on active chlorine.
The composition according to claim 1. 13. Low sensitivity to said water hardness
If the pH buffering means is used in a 1 M solution at pH 10, 25 ° C
13. The composition according to claim 1 or 12, wherein more than 3.5 mM calcium ions are required in order to precipitate the calcium salt of the alkali anion of said pH buffering means. 14. The composition according to claim 1, wherein the pH buffering means is an alkali metal salt of metaborate or stannate or a mixture thereof. 15. The composition of claim 1, wherein the composition comprises 0.01 to 20% by weight of the total composition of the pH buffering means.
A composition according to any one of the preceding claims. 16. The composition comprises up to 5% by weight of the total composition of a precipitant, and wherein the precipitant comprises a carbonate,
The composition according to any one of claims 1, 12 to 15, which is a polycarbonate, sesquicarbonate, silicate, alkali metal salt of polysilicate, or a mixture thereof. 17. The composition according to claim 1, wherein the pH of the composition is 9-13.5.