CA2006530C - Bleaching composition - Google Patents
Bleaching compositionInfo
- Publication number
- CA2006530C CA2006530C CA002006530A CA2006530A CA2006530C CA 2006530 C CA2006530 C CA 2006530C CA 002006530 A CA002006530 A CA 002006530A CA 2006530 A CA2006530 A CA 2006530A CA 2006530 C CA2006530 C CA 2006530C
- Authority
- CA
- Canada
- Prior art keywords
- surfactant
- composition
- hydrogen peroxide
- solution
- stannic oxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/39—Organic or inorganic per-compounds
- C11D3/3902—Organic or inorganic per-compounds combined with specific additives
- C11D3/3937—Stabilising agents
- C11D3/394—Organic compounds
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
- C11D1/02—Anionic compounds
- C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
- C11D1/29—Sulfates of polyoxyalkylene ethers
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
- C11D1/66—Non-ionic compounds
- C11D1/83—Mixtures of non-ionic with anionic compounds
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/39—Organic or inorganic per-compounds
- C11D3/3947—Liquid compositions
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
- C11D1/02—Anionic compounds
- C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
- C11D1/14—Sulfonic acids or sulfuric acid esters; Salts thereof derived from aliphatic hydrocarbons or mono-alcohols
- C11D1/143—Sulfonic acid esters
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
- C11D1/02—Anionic compounds
- C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
- C11D1/14—Sulfonic acids or sulfuric acid esters; Salts thereof derived from aliphatic hydrocarbons or mono-alcohols
- C11D1/146—Sulfuric acid esters
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
- C11D1/66—Non-ionic compounds
- C11D1/75—Amino oxides
Abstract
Solutions of hydrogen peroxide which are alkaline, and which are thickened with a combination of surfactant and electrolyte, can be stabilised with colloidal hydrous stannic oxide.
Description
2006~30 -BLEACHING COMPOSITION
This invention relates to liquid bleach compositions which may be thickened liquids suitable for sale and use as a domestic bleach. The compositions of the invention may be pourable liquids, albeit more viscous than water, or may be even more viscous liquids which cannot be poured easily. Thickening of a pourable domestic bleach helps the user to control dispensing of the composition and retards drainage from surfaces to which it is applied.
A domestic bleach needs to be adequately stable so that a substantial proportion of the bleaching agent survives during storage between manufacture and use. Prior to the present invention, commercial liquid bleach products have frequently utilised hypochlorite as bleaching agent.
It is well known that hydrogen peroxide is unstable unless stabilising agents are present. These counteract decomposition catalysed by transition metal ions. Hydrogen peroxide gives better bleaching action if used under alkaline conditions. However, stabilisation of hydrogen peroxide under alkaline conditions is difficult and in consequence commercial solutions of hydrogen peroxide have generally been acidic for the sake of stability.
EP-B-9839 discloses that the stabilisation of hydrogen peroxide under alkaline conditions can be accomplished using certain specified phosphonate compounds.
It also contains comparative results testing the effectiveness of various materials as stabilisers under alkaline conditions. These comparative results show that many materials which are known to stabilise acidic hydrogen peroxide have very little effect under alkaline conditions.
One material which has been disclosed as a stabiliser for hydrogen peroxide in acidic solution is colloidal hydrous stannic oxide. US 3781409 and US 3607053 are examples of disclosures of the use of sodium stannate as a stabilising agent for acidic hydrogen peroxide solution.
In these US patents the sodium stannate is dissolved in an alkaline but peroxide-free solution which is then added as a stabiliser to very much larger volumes of acidic hydrogen peroxide solution. The sodium stannate will undergo hydrolysis to colloidal hydrous stannic oxide in the solution. The alkaline solution contains other salts in addition to sodium stannate but these are diluted to a very low electrolyte level when added to the acidic hydrogen peroxide solution.
Pourable domestic liquid bleach is frequently thickened by including one or more surfactants which, in the presence of electrolyte, act to thicken the solution so that it becomes more viscous than water.
The presence of electrolyte tends to cause decomposition of alkaline hydrogen peroxide solution. For instance, we have found that a 4% by weight solution of hydrogen peroxide, made alkaline to pH 10 and containing 0.25% of ethylene diamine tetramethylene phosphonic acid as stabiliser (which is not as effective as phosphonates in -accordance with EP-B-9839) was found to retain 95% of its hydrogen peroxide after two weeks storage at 37C. By contrast, 85% or less of the hydrogen peroxide was retained if the solution also contained 1% by weight of sodium chloride, while only about 50% of the hydrogen peroxide was retained if the solution contained 10% by weight of sodium chloride. Similar results were observed using sodium tripolyphosphate rather than sodium chloride as the added electrolyte. Doubling the quantity of the phosphonate stabiliser had little effect on the rate of decomposition.
Thus, any attempt to make a surfactant-thickened, alkaline domestic liquid bleach product using hydrogen peroxide as the bleaching agent would encounter the potential problem that the thickening of the solution would require the presence of some electrolyte but that this electrolyte would serve to accelerate decomposition of the peroxide.
A further potential problem arises because electrolyte inherently tends to bring about flocculation of colloidal suspensions. Consequently the presence of electrolyte also has the potential to bring about a reduction of the effectiveness of any stabilising agent which is in the form of a colloidal suspension.
It is surprising that - as we have now found -colloidal hydrous stannic oxide can act as a very effectivestabilising agent for alkaline hydrogen peroxide solutions.
It is also surprising that colloidal hydrous stannic oxide will tolerate the inclusion of surfactant and electrolyte in sufficient quantities to effect thickening.
In a first aspect, therefore, the present invention provides a liquid bleaching composition comprising an aqueous alkaline solution, wherein the total quantity of inorganic salts in the composition does not exceed 5% by weight 5 based on the whole composition, said solution comprising:
a) 0.05-0.30 molar electrolyte, b) 0.75-3.0%wt of at least one surfactant which thickens in the presence of the electrolyte (a) so as to increase the viscosity of the composition, c) 2-10%wt of hydrogen peroxide, and, d) an effective amount of colloidal hydrous stannic oxide as a stabilizer for the hydrogen peroxide.
The colloidal hydrous stannic oxide which is used as a stabilising agent is preferably formed in-situ in the solution as the product of hydrolysis of a soluble 15 tin compound. Consequently in a second aspect this invention provides a method of preparing a liquid bleaching composition which comprises including in the composition, successively or together, hydrogen peroxide, sufficient alkaline material to give the solution an alkaline pH, and a tin compound capable of hydrolysis to stannic oxide, so that the tin compound is hydrolysed in 2 0 the solution to colloidal hydrous stannic oxide. The hydrolysis may take place in a solution which is already thickened by the presence of surfactant therein, even though the peroxide may not yet have been added to the solution. Various tin compounds can be added to the solution to undergo hydrolysis to form the stannic oxide. Those preferred are tin sulphate and sodium v ~
Z0~)6530 . ~ --stannate. Other tin compounds can be used, including tin dichloride and tin tetrachloride.
The concentrations of tin compound included in the composition may lie in the range from 10- 4 molar to 10- 2 molar, preferably 3 x 10- 3 to 6 x 10- 3 molar. The quantity of tin compound should not be substantially greater than necessary, since excess of it can itself cause peroxide decomposition. An optimum concentration of the tin compound can be determined by making test solutions with various concentrations of the tin compound and analytically determining the amount of peroxide retained on storage.
The compositions of this invention preferably have a pH in the range from 8.0 to 10.5, better 8.5 to 9.8 or 10.0, yet more preferably 8.7 to 9.3. A buffer may be included to set the pH.
As already mentioned above, it is preferred to include at least one surfactant to increase the viscosity of the composition. It is desirable that this surfactant or surfactants has the ability to thicken a solution in the presence of a fairly low electrolyte concentration. This may make it possible for the electrolyte to be provided by salts which are in the composition for another purpose, without deliberate addition of any salt for the sole purpose of enhancing ionic strength. Since electrolyte is known to be detrimental to hydrogen peroxide stability, it is desirable to keep the electrolyte concentration low. A
further benefit of a low electrolyte concentration is a reduced tendency for the composition to leave streaks on a surface which is cleaned with it.
One surfactant which is suitable to effect thickening is alkyl ether sulphate having the formula:
R ( OC2 H4 )n OSO3 M
where R is an alkyl group, preferably linear alkyl, containing 8 to 20 carbon atoms, n has an average value in the range from 0.5 to 12 better 1 to 6 and M is a solubilising cation, preferably alkali metal such as sodium.
A pair of surfactants used to effect thickening may be a combination of a nonionic or amphoteric surfactant together with an anionic surfactant. Two specific possibilities are the combinations of:
i) an amine oxide surfactant, preferably a trialkyl amine oxide with one long chain alkyl of 8 to 20 carbon atoms and two alkyl groups of 1 to 4 carbon atoms; and ii) an anionic surfactant which is either primary alcohol sulphate with 8 to 20 carbon atoms in the alkyl group thereof or alkane sulphonate derived from alkane of 8 to 20 carbon atoms.
Further surfactants may also be present. The total amount of surfactant(s) included may be a small proportion of the composition, for example the thickening surfactant(s) may constitute 0.75 to 3% of the composition.
Larger amounts, giving greater viscosity, may be used but are less preferred.
When primary alcohol sulphate is employed, the weight ratio of amine oxide:alcohol sulphate preferably ranges from 82:18 or 80:20 to 65:35, better 80:20 to 70:30.
7 200653~
Alkane sulphonate ls preferred over alcohol sulphate, because the vlscoslty is less sensitive to changes in the compositlon, so making it easler to produce an end product with repeatable viscosity. The weight ratio of amine oxide to alkane sulphonate ls preferably in the range from 80:20 to 50:50 or 65:35, better 70:30 to 65:35.
An appropriate viscosity for a pourable composition having the appearance of a thick liquid is a dynamic viscosity in the range from 50 to 250 centipoise (0.05 to 0.25 Pa.sec), preferably about 100 centipoise (0.1 Pa.sec). More viscous liquids for example with viscosity in the range from 250 to 1000 cent~poise or more are also within the scope of the invention.
Since the compositions of this invention are generally aqueous, they will usually have specific yravity close to unity. Consequently values of kinematic viscosities (in stokes) will be numerically approximately iiB
200~30 _, the same as values of dynamic viscosity (in poise). Dynamic viscosities expressed in Pascal.sec will be approximately 1000 times kinetic viscosities expressed in m2.sec~1.
Example 1 Formulations were prepared containing the constituents set out in Table 1 below. The compositions were stored in plastic bottles at 37C. At intervals aliquots were removed and titrated with potassium permanganate to determine the level of hydrogen peroxide remaining. Results are included in Table 1.
The viscosity of these formulations was measured using a Ubbelohde capillary viscometer and found to be approximately lOOcS.
-% by weight Constituent A B C
5 Hydrogen peroxide 5 5 5 (reckoned as anhydrous) Tallow dimethylamine oxide 1.0 1.0 1.0 Sodium alkane sulphonate 0.5 0.5 0.5 Perfume 1.0 1.0 1.0 Tetrasodium pyrophosphate 1.8 - -(reckoned as anhydrous) Phosphonate stabiliser 0.15 - -according to EP 9839 20 Borax (reckoned as anhydrous) - 1.6 1.6 Sodium stannate trihydrate - 0.5 0.1 Sodium hydroxide to give: pH 9.6 pH 9.6 pH 9.0 Water ----- balance to 100% -----Hz 2 remaining after 50 days: 85% 79%
H2 2 remaining after 100 days: 96%
The stabiliser in accordance with EP 9839 was diethylene triamine penta (methylene phosphonic acid).
Example 2 The procedure of Example 1 was repeated, using formulations with the same amounts of hydrogen peroxide, surfactant, perfume and dye. Various tin compounds were used at a concentration of 6 x 10- 3 molar, both with and without 3.0% borax decahydrate. Glass bottles were used, which are somewhat detrimental to stability. In every case pH was 9.6 initially. Proportions of hydrogen peroxide remaining after 28 days were:-SnCl2 with borax 68%
5 Na2SnO3 with borax 47%
SnS04 with borax 45%
Na2SnO3 without borax 96%
SnS04 without borax 95%
Example 3 The procedure of Example 1 was repeated using adifferent surfactant and with stannous chloride as the tin salt. The surfactant used was a linear alkyl ether sulphate of general formula:
R(OC2H4) n 0S03 Na where the alkyl group R was C1 2 and C1 3 linear alkyl groups, and n had an average value of 3. A comparative experiment replaced the stannous-chloride with the same phosphonate stabiliser according to EP 9839 as used in Example 1. The formulations and results are set out in the following Table. Viscosities were determined using a Haake roto-viscometer and were approximately lOOcP at a shear rate of 21 sec~l.
20~)6530 -% by weight Constituent A B
Hydrogen peroxide 5 5 (reckoned as anhydrous) Alkyl ether sulphate 1.25 1.25 Sodium chloride 6.5 6.5 Perfume 0.08 0.08 Stannous chloride dihydrate 0.14 Phosphonate stabiliser according to EP 9839 - 0.15 Sodium hydroxide to give: pH 9.6 pH 9.6 20 Water -- balance to 100% --H2 2 remaining after 5 weeks at 37C 80% 79%
Example 4 An alkaline solution of hydrogen peroxide was prepared containing 4% by weight hydrogen peroxide (reckoned as anhydrous) sodium hydroxide to give a pH of 10 and a 5.7 x 10- 3 molar quantity of stannic chloride which hydrolysed to colloidal hydrous stannic oxide.
The composition was stored at 40C and the amount of hydrogen peroxide remaining was determined analytically at intervals. It was found that 75% of the hydrogen peroxide remained after 3 weeks.
Although this test was made without surfactant or much electrolyte present, it confirms the effectiveness of colloidal stannic oxide as a stabiliser in alkaline solution.
Example 5 Alkaline solutions of hydrogen peroxide were prepared containing surfactant, sodium chloride and stannic chloride which hydrolysed to colloidal hydrous stannic oxide. Two surfactant combinations were used.
The quantities of surfactant and sodium chloride were such as to give viscosities well in excess of that preferred for a pourable type of bleach product. Smaller quantities could be used to give a "thick liquid" type of bleach product.
In each case the initial concentration of hydrogen peroxide, reckoned as anhydrous, was 4% by weight.
The solutions were made alkaline to pH 10 with sodium hydroxide.
Stannic chloride was used at a concentration of 2.3 x 10- 3 molar.
One surfactant system consisted of 4.5~ by weight of C1 2 -Cl 4 alkyl dimethyl amine oxide and 4.5% by weight sodium lauryl sulphate. This was used with a sodium chloride concentration of 9% by weight.
The second surfactant system consisted of 5% by weight of C11-C1 5 secondary alcohol ethoxylated with average 3 ethylene oxide residues, and 5~ by weight of sodium lauryl sulphate. This combination was used with 3.37% by weight sodium chloride.
The solutions were stored at 40C and the amount of hydrogen peroxide remaining was determined at intervals.
20065~0 It was found that the amounts of hydrogen peroxide remaining were between 80 and 85% with either of the surfactant combinations.
Example 6 A base solution was prepared containing tallow dimethylamine oxide, sodium alkane sulphonate and borax.
This was used to make up solutions containing hydrogen peroxide and colloidal stannic oxide, but two procedures were used.
In one procedure stannous chloride dihydrate was added to the base solution and stirred until it was completely dissolved or dispersed, after which hydrogen peroxide solution was added. The solution pH at this stage was 6.5. It was adjusted to pH 9.9 by adding 20% w/v sodium hydroxide solution and some distilled water.
The quantities used were such that the composition contained:
20 Hydrogen peroxide 4.98g (reckoned as anhydrous) Tallow dimethylamine oxide 0.98g 25 Sodium alkane sulphonate 0.48g Borax (reckoned as anhydrous) 1.6 g SnCl2.2H20 0.14g Sodium hydroxide to give: pH 9.9 Water balance to lOOg total 2~06530 In the alternative procedure a suspension of stannic oxide was prepared by dissolving 5g of stannous chloride dihydrate in approximately 115g distilled water, and then adding sodium hydroxide solution to give a pH of 5 9.7. The resulting suspension of stannic oxide was stored overnight.
Hydrogen peroxide was added to the base solution, followed by sodium hydroxide solution and some distilled water to give a pH of 9.9. A small quantity of suspension 10 was then added. This was calculated to be the quantity of suspension produced from 0.14g of SnCl2.2H20. Other quantities were as for the first procedure.
The solutions were both stored at 37C (to accelerate aging) and the concentration of hydrogen peroxide remaining was determined by analysis after 48 and 120 hours.
The results were as follows:
H2O2 concentrations After After Initially48 hours120 hours Stannic oxide formed in presence of H2 2 and 4.98 4.95 4.88 surfactant Stannic oxide formed separately 4.98 4.81 4.82 and aged
This invention relates to liquid bleach compositions which may be thickened liquids suitable for sale and use as a domestic bleach. The compositions of the invention may be pourable liquids, albeit more viscous than water, or may be even more viscous liquids which cannot be poured easily. Thickening of a pourable domestic bleach helps the user to control dispensing of the composition and retards drainage from surfaces to which it is applied.
A domestic bleach needs to be adequately stable so that a substantial proportion of the bleaching agent survives during storage between manufacture and use. Prior to the present invention, commercial liquid bleach products have frequently utilised hypochlorite as bleaching agent.
It is well known that hydrogen peroxide is unstable unless stabilising agents are present. These counteract decomposition catalysed by transition metal ions. Hydrogen peroxide gives better bleaching action if used under alkaline conditions. However, stabilisation of hydrogen peroxide under alkaline conditions is difficult and in consequence commercial solutions of hydrogen peroxide have generally been acidic for the sake of stability.
EP-B-9839 discloses that the stabilisation of hydrogen peroxide under alkaline conditions can be accomplished using certain specified phosphonate compounds.
It also contains comparative results testing the effectiveness of various materials as stabilisers under alkaline conditions. These comparative results show that many materials which are known to stabilise acidic hydrogen peroxide have very little effect under alkaline conditions.
One material which has been disclosed as a stabiliser for hydrogen peroxide in acidic solution is colloidal hydrous stannic oxide. US 3781409 and US 3607053 are examples of disclosures of the use of sodium stannate as a stabilising agent for acidic hydrogen peroxide solution.
In these US patents the sodium stannate is dissolved in an alkaline but peroxide-free solution which is then added as a stabiliser to very much larger volumes of acidic hydrogen peroxide solution. The sodium stannate will undergo hydrolysis to colloidal hydrous stannic oxide in the solution. The alkaline solution contains other salts in addition to sodium stannate but these are diluted to a very low electrolyte level when added to the acidic hydrogen peroxide solution.
Pourable domestic liquid bleach is frequently thickened by including one or more surfactants which, in the presence of electrolyte, act to thicken the solution so that it becomes more viscous than water.
The presence of electrolyte tends to cause decomposition of alkaline hydrogen peroxide solution. For instance, we have found that a 4% by weight solution of hydrogen peroxide, made alkaline to pH 10 and containing 0.25% of ethylene diamine tetramethylene phosphonic acid as stabiliser (which is not as effective as phosphonates in -accordance with EP-B-9839) was found to retain 95% of its hydrogen peroxide after two weeks storage at 37C. By contrast, 85% or less of the hydrogen peroxide was retained if the solution also contained 1% by weight of sodium chloride, while only about 50% of the hydrogen peroxide was retained if the solution contained 10% by weight of sodium chloride. Similar results were observed using sodium tripolyphosphate rather than sodium chloride as the added electrolyte. Doubling the quantity of the phosphonate stabiliser had little effect on the rate of decomposition.
Thus, any attempt to make a surfactant-thickened, alkaline domestic liquid bleach product using hydrogen peroxide as the bleaching agent would encounter the potential problem that the thickening of the solution would require the presence of some electrolyte but that this electrolyte would serve to accelerate decomposition of the peroxide.
A further potential problem arises because electrolyte inherently tends to bring about flocculation of colloidal suspensions. Consequently the presence of electrolyte also has the potential to bring about a reduction of the effectiveness of any stabilising agent which is in the form of a colloidal suspension.
It is surprising that - as we have now found -colloidal hydrous stannic oxide can act as a very effectivestabilising agent for alkaline hydrogen peroxide solutions.
It is also surprising that colloidal hydrous stannic oxide will tolerate the inclusion of surfactant and electrolyte in sufficient quantities to effect thickening.
In a first aspect, therefore, the present invention provides a liquid bleaching composition comprising an aqueous alkaline solution, wherein the total quantity of inorganic salts in the composition does not exceed 5% by weight 5 based on the whole composition, said solution comprising:
a) 0.05-0.30 molar electrolyte, b) 0.75-3.0%wt of at least one surfactant which thickens in the presence of the electrolyte (a) so as to increase the viscosity of the composition, c) 2-10%wt of hydrogen peroxide, and, d) an effective amount of colloidal hydrous stannic oxide as a stabilizer for the hydrogen peroxide.
The colloidal hydrous stannic oxide which is used as a stabilising agent is preferably formed in-situ in the solution as the product of hydrolysis of a soluble 15 tin compound. Consequently in a second aspect this invention provides a method of preparing a liquid bleaching composition which comprises including in the composition, successively or together, hydrogen peroxide, sufficient alkaline material to give the solution an alkaline pH, and a tin compound capable of hydrolysis to stannic oxide, so that the tin compound is hydrolysed in 2 0 the solution to colloidal hydrous stannic oxide. The hydrolysis may take place in a solution which is already thickened by the presence of surfactant therein, even though the peroxide may not yet have been added to the solution. Various tin compounds can be added to the solution to undergo hydrolysis to form the stannic oxide. Those preferred are tin sulphate and sodium v ~
Z0~)6530 . ~ --stannate. Other tin compounds can be used, including tin dichloride and tin tetrachloride.
The concentrations of tin compound included in the composition may lie in the range from 10- 4 molar to 10- 2 molar, preferably 3 x 10- 3 to 6 x 10- 3 molar. The quantity of tin compound should not be substantially greater than necessary, since excess of it can itself cause peroxide decomposition. An optimum concentration of the tin compound can be determined by making test solutions with various concentrations of the tin compound and analytically determining the amount of peroxide retained on storage.
The compositions of this invention preferably have a pH in the range from 8.0 to 10.5, better 8.5 to 9.8 or 10.0, yet more preferably 8.7 to 9.3. A buffer may be included to set the pH.
As already mentioned above, it is preferred to include at least one surfactant to increase the viscosity of the composition. It is desirable that this surfactant or surfactants has the ability to thicken a solution in the presence of a fairly low electrolyte concentration. This may make it possible for the electrolyte to be provided by salts which are in the composition for another purpose, without deliberate addition of any salt for the sole purpose of enhancing ionic strength. Since electrolyte is known to be detrimental to hydrogen peroxide stability, it is desirable to keep the electrolyte concentration low. A
further benefit of a low electrolyte concentration is a reduced tendency for the composition to leave streaks on a surface which is cleaned with it.
One surfactant which is suitable to effect thickening is alkyl ether sulphate having the formula:
R ( OC2 H4 )n OSO3 M
where R is an alkyl group, preferably linear alkyl, containing 8 to 20 carbon atoms, n has an average value in the range from 0.5 to 12 better 1 to 6 and M is a solubilising cation, preferably alkali metal such as sodium.
A pair of surfactants used to effect thickening may be a combination of a nonionic or amphoteric surfactant together with an anionic surfactant. Two specific possibilities are the combinations of:
i) an amine oxide surfactant, preferably a trialkyl amine oxide with one long chain alkyl of 8 to 20 carbon atoms and two alkyl groups of 1 to 4 carbon atoms; and ii) an anionic surfactant which is either primary alcohol sulphate with 8 to 20 carbon atoms in the alkyl group thereof or alkane sulphonate derived from alkane of 8 to 20 carbon atoms.
Further surfactants may also be present. The total amount of surfactant(s) included may be a small proportion of the composition, for example the thickening surfactant(s) may constitute 0.75 to 3% of the composition.
Larger amounts, giving greater viscosity, may be used but are less preferred.
When primary alcohol sulphate is employed, the weight ratio of amine oxide:alcohol sulphate preferably ranges from 82:18 or 80:20 to 65:35, better 80:20 to 70:30.
7 200653~
Alkane sulphonate ls preferred over alcohol sulphate, because the vlscoslty is less sensitive to changes in the compositlon, so making it easler to produce an end product with repeatable viscosity. The weight ratio of amine oxide to alkane sulphonate ls preferably in the range from 80:20 to 50:50 or 65:35, better 70:30 to 65:35.
An appropriate viscosity for a pourable composition having the appearance of a thick liquid is a dynamic viscosity in the range from 50 to 250 centipoise (0.05 to 0.25 Pa.sec), preferably about 100 centipoise (0.1 Pa.sec). More viscous liquids for example with viscosity in the range from 250 to 1000 cent~poise or more are also within the scope of the invention.
Since the compositions of this invention are generally aqueous, they will usually have specific yravity close to unity. Consequently values of kinematic viscosities (in stokes) will be numerically approximately iiB
200~30 _, the same as values of dynamic viscosity (in poise). Dynamic viscosities expressed in Pascal.sec will be approximately 1000 times kinetic viscosities expressed in m2.sec~1.
Example 1 Formulations were prepared containing the constituents set out in Table 1 below. The compositions were stored in plastic bottles at 37C. At intervals aliquots were removed and titrated with potassium permanganate to determine the level of hydrogen peroxide remaining. Results are included in Table 1.
The viscosity of these formulations was measured using a Ubbelohde capillary viscometer and found to be approximately lOOcS.
-% by weight Constituent A B C
5 Hydrogen peroxide 5 5 5 (reckoned as anhydrous) Tallow dimethylamine oxide 1.0 1.0 1.0 Sodium alkane sulphonate 0.5 0.5 0.5 Perfume 1.0 1.0 1.0 Tetrasodium pyrophosphate 1.8 - -(reckoned as anhydrous) Phosphonate stabiliser 0.15 - -according to EP 9839 20 Borax (reckoned as anhydrous) - 1.6 1.6 Sodium stannate trihydrate - 0.5 0.1 Sodium hydroxide to give: pH 9.6 pH 9.6 pH 9.0 Water ----- balance to 100% -----Hz 2 remaining after 50 days: 85% 79%
H2 2 remaining after 100 days: 96%
The stabiliser in accordance with EP 9839 was diethylene triamine penta (methylene phosphonic acid).
Example 2 The procedure of Example 1 was repeated, using formulations with the same amounts of hydrogen peroxide, surfactant, perfume and dye. Various tin compounds were used at a concentration of 6 x 10- 3 molar, both with and without 3.0% borax decahydrate. Glass bottles were used, which are somewhat detrimental to stability. In every case pH was 9.6 initially. Proportions of hydrogen peroxide remaining after 28 days were:-SnCl2 with borax 68%
5 Na2SnO3 with borax 47%
SnS04 with borax 45%
Na2SnO3 without borax 96%
SnS04 without borax 95%
Example 3 The procedure of Example 1 was repeated using adifferent surfactant and with stannous chloride as the tin salt. The surfactant used was a linear alkyl ether sulphate of general formula:
R(OC2H4) n 0S03 Na where the alkyl group R was C1 2 and C1 3 linear alkyl groups, and n had an average value of 3. A comparative experiment replaced the stannous-chloride with the same phosphonate stabiliser according to EP 9839 as used in Example 1. The formulations and results are set out in the following Table. Viscosities were determined using a Haake roto-viscometer and were approximately lOOcP at a shear rate of 21 sec~l.
20~)6530 -% by weight Constituent A B
Hydrogen peroxide 5 5 (reckoned as anhydrous) Alkyl ether sulphate 1.25 1.25 Sodium chloride 6.5 6.5 Perfume 0.08 0.08 Stannous chloride dihydrate 0.14 Phosphonate stabiliser according to EP 9839 - 0.15 Sodium hydroxide to give: pH 9.6 pH 9.6 20 Water -- balance to 100% --H2 2 remaining after 5 weeks at 37C 80% 79%
Example 4 An alkaline solution of hydrogen peroxide was prepared containing 4% by weight hydrogen peroxide (reckoned as anhydrous) sodium hydroxide to give a pH of 10 and a 5.7 x 10- 3 molar quantity of stannic chloride which hydrolysed to colloidal hydrous stannic oxide.
The composition was stored at 40C and the amount of hydrogen peroxide remaining was determined analytically at intervals. It was found that 75% of the hydrogen peroxide remained after 3 weeks.
Although this test was made without surfactant or much electrolyte present, it confirms the effectiveness of colloidal stannic oxide as a stabiliser in alkaline solution.
Example 5 Alkaline solutions of hydrogen peroxide were prepared containing surfactant, sodium chloride and stannic chloride which hydrolysed to colloidal hydrous stannic oxide. Two surfactant combinations were used.
The quantities of surfactant and sodium chloride were such as to give viscosities well in excess of that preferred for a pourable type of bleach product. Smaller quantities could be used to give a "thick liquid" type of bleach product.
In each case the initial concentration of hydrogen peroxide, reckoned as anhydrous, was 4% by weight.
The solutions were made alkaline to pH 10 with sodium hydroxide.
Stannic chloride was used at a concentration of 2.3 x 10- 3 molar.
One surfactant system consisted of 4.5~ by weight of C1 2 -Cl 4 alkyl dimethyl amine oxide and 4.5% by weight sodium lauryl sulphate. This was used with a sodium chloride concentration of 9% by weight.
The second surfactant system consisted of 5% by weight of C11-C1 5 secondary alcohol ethoxylated with average 3 ethylene oxide residues, and 5~ by weight of sodium lauryl sulphate. This combination was used with 3.37% by weight sodium chloride.
The solutions were stored at 40C and the amount of hydrogen peroxide remaining was determined at intervals.
20065~0 It was found that the amounts of hydrogen peroxide remaining were between 80 and 85% with either of the surfactant combinations.
Example 6 A base solution was prepared containing tallow dimethylamine oxide, sodium alkane sulphonate and borax.
This was used to make up solutions containing hydrogen peroxide and colloidal stannic oxide, but two procedures were used.
In one procedure stannous chloride dihydrate was added to the base solution and stirred until it was completely dissolved or dispersed, after which hydrogen peroxide solution was added. The solution pH at this stage was 6.5. It was adjusted to pH 9.9 by adding 20% w/v sodium hydroxide solution and some distilled water.
The quantities used were such that the composition contained:
20 Hydrogen peroxide 4.98g (reckoned as anhydrous) Tallow dimethylamine oxide 0.98g 25 Sodium alkane sulphonate 0.48g Borax (reckoned as anhydrous) 1.6 g SnCl2.2H20 0.14g Sodium hydroxide to give: pH 9.9 Water balance to lOOg total 2~06530 In the alternative procedure a suspension of stannic oxide was prepared by dissolving 5g of stannous chloride dihydrate in approximately 115g distilled water, and then adding sodium hydroxide solution to give a pH of 5 9.7. The resulting suspension of stannic oxide was stored overnight.
Hydrogen peroxide was added to the base solution, followed by sodium hydroxide solution and some distilled water to give a pH of 9.9. A small quantity of suspension 10 was then added. This was calculated to be the quantity of suspension produced from 0.14g of SnCl2.2H20. Other quantities were as for the first procedure.
The solutions were both stored at 37C (to accelerate aging) and the concentration of hydrogen peroxide remaining was determined by analysis after 48 and 120 hours.
The results were as follows:
H2O2 concentrations After After Initially48 hours120 hours Stannic oxide formed in presence of H2 2 and 4.98 4.95 4.88 surfactant Stannic oxide formed separately 4.98 4.81 4.82 and aged
Claims (7)
1. A liquid bleaching composition comprising an aqueous alkaline solution, wherein the total quantity of inorganic salts in the composition does not exceed 5% by weight based on the whole composition, said solution comprising:
a) 0.05-0.30 molar electrolyte, b) 0.75-3.0%wt of at least one surfactant which thickens in the presence of the electrolyte (a) so as to increase the viscosity of the composition, c) 2-10%wt of hydrogen peroxide, and, d) an effective amount of colloidal hydrous stannic oxide as a stabilizer for the hydrogen peroxide.
a) 0.05-0.30 molar electrolyte, b) 0.75-3.0%wt of at least one surfactant which thickens in the presence of the electrolyte (a) so as to increase the viscosity of the composition, c) 2-10%wt of hydrogen peroxide, and, d) an effective amount of colloidal hydrous stannic oxide as a stabilizer for the hydrogen peroxide.
2. A composition according to claim 1 wherein the surfactant is an alkyl ether sulphate of the formula:
R(OC2H4)nOSO3M
where R is an alkyl group containing 8 to 20 carbon atoms, n has an average value in the range from 0.5 to 12 and M is a solubilising cation.
R(OC2H4)nOSO3M
where R is an alkyl group containing 8 to 20 carbon atoms, n has an average value in the range from 0.5 to 12 and M is a solubilising cation.
3. A composition according to claim 1 wherein the surfactant is a combination of a nonionic or amphoteric surfactant and an anionic surfactant.
4. A composition according to claim 1 or claim 2 wherein the surfactant is a combination of (i) a trialkyl amine oxide having one C8 to C20 alkyl group and two C1 to C4 alkyl groups and (ii) either a C8 to C20 alkane sulphonate or a C8 to C20 alcohol sulphate.
5. A composition according to claim 1 wherein the colloidal hydrous stannic oxide is formed by hydrolysis of a soluble tin compound which is present in the range from 10-4 to 10-2 molar.
6. A composition according to claim 1 wherein the pH is in the range from 8.5 to 9.3.
7. A method of preparing a liquid bleaching composition which method comprises including in the composition, successively or together, hydrogen peroxide, sufficient alkaline material to give the solution an alkaline pH, preferably in the range 8.5 to 10, and a tin compound capable of hydrolysis to stannic oxide, so that the tin compound is hydrolysed in the solution to colloidal hydrous stannic oxide.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8830296.3 | 1988-12-28 | ||
| GB888830296A GB8830296D0 (en) | 1988-12-28 | 1988-12-28 | Bleaching composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2006530A1 CA2006530A1 (en) | 1990-06-28 |
| CA2006530C true CA2006530C (en) | 1996-10-15 |
Family
ID=10649218
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002006530A Expired - Fee Related CA2006530C (en) | 1988-12-28 | 1989-12-22 | Bleaching composition |
| CA002006531A Expired - Fee Related CA2006531C (en) | 1988-12-28 | 1989-12-22 | Bleaching composition |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002006531A Expired - Fee Related CA2006531C (en) | 1988-12-28 | 1989-12-22 | Bleaching composition |
Country Status (11)
| Country | Link |
|---|---|
| EP (2) | EP0376706B1 (en) |
| JP (2) | JP2562064B2 (en) |
| AU (2) | AU623961B2 (en) |
| BR (2) | BR8906844A (en) |
| CA (2) | CA2006530C (en) |
| DE (2) | DE68921182T2 (en) |
| ES (2) | ES2067558T3 (en) |
| GB (1) | GB8830296D0 (en) |
| IN (2) | IN170708B (en) |
| NO (2) | NO172354C (en) |
| ZA (2) | ZA899842B (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8830296D0 (en) * | 1988-12-28 | 1989-02-22 | Unilever Plc | Bleaching composition |
| DE4123142A1 (en) * | 1991-07-12 | 1993-01-14 | Henkel Kgaa | FLUESSIGWASCHMITTEL |
| US5217710A (en) * | 1992-03-05 | 1993-06-08 | Chesebrough-Pond's Usa Co. | Stabilized peroxide gels containing fluoride |
| GB9319943D0 (en) * | 1993-09-28 | 1993-11-17 | Solvay Interox Ltd | Thickened compositions |
| GB2286603B (en) * | 1994-02-14 | 1998-03-25 | Jeyes Group Plc | Bleach compositions |
| DE4413433C2 (en) * | 1994-04-18 | 1999-09-16 | Henkel Kgaa | Aqueous bleach |
| US5492540A (en) * | 1994-06-13 | 1996-02-20 | S. C. Johnson & Son, Inc. | Soft surface cleaning composition and method with hydrogen peroxide |
| DK0769047T3 (en) * | 1994-07-01 | 1999-09-27 | Warwick Int Group | Bleaching Compositions |
| US5736497A (en) * | 1995-05-05 | 1998-04-07 | Degussa Corporation | Phosphorus free stabilized alkaline peroxygen solutions |
| DE19623571C2 (en) * | 1996-06-13 | 2000-06-08 | Cognis Deutschland Gmbh | Thickener for aqueous hydrogen peroxide solutions |
| BR9704210A (en) * | 1997-07-31 | 1999-02-02 | Unilever Nv | Detergent composition and dish washing process |
| GB9812457D0 (en) * | 1998-06-10 | 1998-08-05 | Secr Defence | Surface coatings |
| AU741580B2 (en) * | 1998-06-23 | 2001-12-06 | Saban Ventures Pty Limited | Improved disinfection |
| ATE293675T1 (en) * | 1998-10-22 | 2005-05-15 | Colgate Palmolive Co | THICKENED LIQUID HYDROGEN PEROXIDE BLEACH COMPOSITION |
| GB2349892A (en) * | 1999-05-13 | 2000-11-15 | Warwick Internat Group Ltd | Metal cleaning |
| GB2397823A (en) * | 2003-01-31 | 2004-08-04 | Reckitt Benckiser Nv | Aqueous cleaning compositions |
| GB2401875A (en) * | 2003-05-22 | 2004-11-24 | Reckitt Benckiser Nv | Aqueous cleaning compositions |
| ITMI20031543A1 (en) * | 2003-07-28 | 2005-01-29 | De Nora Elettrodi Spa | ELECTRODE FOR ELECTROCHEMICAL PROCESSES AND METHOD FOR ITS ACHIEVEMENT |
| US7169237B2 (en) | 2004-04-08 | 2007-01-30 | Arkema Inc. | Stabilization of alkaline hydrogen peroxide |
| US7431775B2 (en) | 2004-04-08 | 2008-10-07 | Arkema Inc. | Liquid detergent formulation with hydrogen peroxide |
| US7045493B2 (en) | 2004-07-09 | 2006-05-16 | Arkema Inc. | Stabilized thickened hydrogen peroxide containing compositions |
| DE102005000955B4 (en) * | 2005-01-07 | 2007-08-30 | Henkel Kgaa | Liquid bleach composition |
| CN105925398B (en) * | 2016-05-17 | 2018-11-23 | 河南工程学院 | A kind of degerming liquid detergent composition and preparation method thereof |
Family Cites Families (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE562380A (en) * | 1956-11-14 | |||
| NL113683C (en) * | 1958-07-10 | |||
| DE1271885B (en) * | 1964-01-04 | 1968-07-04 | Henkel & Cie Gmbh | Liquid, storage-stable detergents, bleaching agents and oxidizing agents |
| US3701825A (en) * | 1970-10-23 | 1972-10-31 | Fmc Corp | Stabilization of hydrogen peroxide with ethylenediamine tetra (methylenephosphonic acid) |
| FR2140822A5 (en) * | 1971-06-09 | 1973-01-19 | Air Liquide | Bleaching liquids - contg hydrogen peroxide or persalts in alkaline medium with stabilisers |
| US4304762A (en) * | 1978-09-27 | 1981-12-08 | Lever Brothers Company | Stabilization of hydrogen peroxide |
| US4299802A (en) * | 1980-03-31 | 1981-11-10 | Union Carbide Corporation | Process for removing carbonyl sulfide from gaseous streams |
| DE3168426D1 (en) * | 1980-04-01 | 1985-03-07 | Interox Chemicals Ltd | Liquid detergent compositions, their manufacture and their use in washing processes |
| JPS56151798A (en) * | 1980-04-01 | 1981-11-24 | Interox Chemicals Ltd | Liquid detergent composition |
| JPS5838800A (en) * | 1981-09-01 | 1983-03-07 | 三菱瓦斯化学株式会社 | Liquid detergent |
| DE3205318A1 (en) * | 1982-02-15 | 1983-08-18 | Henkel KGaA, 4000 Düsseldorf | DISINFECTANT CONCENTRATE |
| CA1205275A (en) * | 1982-06-14 | 1986-06-03 | Kenneth J. Radimer | Stabilization of high purity hydrogen peroxide |
| JPS593006A (en) * | 1982-06-14 | 1984-01-09 | エフ・エム・シ−・コ−ポレ−シヨン | Method of stabilizing high-purity hydrogen peroxide |
| FR2552124B1 (en) * | 1983-09-20 | 1986-09-12 | Ugine Kuhlmann | NOVEL FLUID FORMULATIONS FOR STORAGE-STABLE TEXTILE BLEACH BATHS AND PROCESS FOR OBTAINING SAME |
| JP2783999B2 (en) * | 1985-06-12 | 1998-08-06 | 花王株式会社 | Bleach composition |
| GB8830296D0 (en) * | 1988-12-28 | 1989-02-22 | Unilever Plc | Bleaching composition |
-
1988
- 1988-12-28 GB GB888830296A patent/GB8830296D0/en active Pending
-
1989
- 1989-12-21 ZA ZA899842A patent/ZA899842B/en unknown
- 1989-12-21 ZA ZA899843A patent/ZA899843B/en unknown
- 1989-12-22 AU AU47271/89A patent/AU623961B2/en not_active Ceased
- 1989-12-22 AU AU47272/89A patent/AU624209B2/en not_active Ceased
- 1989-12-22 CA CA002006530A patent/CA2006530C/en not_active Expired - Fee Related
- 1989-12-22 CA CA002006531A patent/CA2006531C/en not_active Expired - Fee Related
- 1989-12-27 IN IN355/BOM/89A patent/IN170708B/en unknown
- 1989-12-27 EP EP89313625A patent/EP0376706B1/en not_active Expired - Lifetime
- 1989-12-27 EP EP89313623A patent/EP0376704B1/en not_active Expired - Lifetime
- 1989-12-27 ES ES89313623T patent/ES2067558T3/en not_active Expired - Lifetime
- 1989-12-27 ES ES89313625T patent/ES2067559T3/en not_active Expired - Lifetime
- 1989-12-27 IN IN354/BOM/89A patent/IN171127B/en unknown
- 1989-12-27 NO NO895261A patent/NO172354C/en not_active IP Right Cessation
- 1989-12-27 DE DE68921182T patent/DE68921182T2/en not_active Expired - Fee Related
- 1989-12-27 DE DE68921181T patent/DE68921181T2/en not_active Expired - Fee Related
- 1989-12-27 NO NO895260A patent/NO173885C/en not_active IP Right Cessation
- 1989-12-28 JP JP1345128A patent/JP2562064B2/en not_active Expired - Fee Related
- 1989-12-28 JP JP1345129A patent/JPH0735520B2/en not_active Expired - Lifetime
- 1989-12-28 BR BR898906844A patent/BR8906844A/en not_active IP Right Cessation
- 1989-12-28 BR BR898906843A patent/BR8906843A/en not_active IP Right Cessation
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