DE102004002355A1 - Powdery mixture containing hydrogen peroxide and hydrophobized silicon dioxide - Google Patents

Abstract

Powdery mixture containing hydrogen peroxide and hydrophobized, pyrogenically prepared silicon dioxide powder, the hydrophobized silicon dioxide powder having a methanol wettability of at least 40 and being less than 9% by weight, based on the total weight, and the proportion of hydrogen peroxide, based on the total weight, between 10 and 50 wt .-% is. DOLLAR A It is produced by treating hydrophobized silicon dioxide powder with a methanol wettability of more than 40 at temperatures of not more than 70 ° C. with an aqueous hydrogen peroxide solution. It can be used in detergents, cleaning agents as well as in skin and hair treatment agents.

Description

object The invention is a powder Mixture containing hydrogen peroxide and hydrophobized silicon dioxide contains and its manufacture and use.

Out DE-A-2013763 is known for producing powdery mixtures, the watery Hydrogen peroxide solution and contain hydrophobized, pyrogenically produced silicon dioxide. The proportion of hydrophobicized silicon dioxide, based on the total weight from hydrogen peroxide solution and hydrophobized silicon dioxide, must be at least 9% by weight be.

Around sufficient fluidity to ensure the mixture the content of hydrophobic silica should preferably be between 10 and 35 wt .-% lie. Such as hydrophobic silicas used with dimethyldichlorosilane or fatty alcohols 8 to 26 carbon atoms were made hydrophobic.

adversely with this mixture there is insufficient stability of hydrogen peroxide in a mixture with hydrophobic silicon dioxide. This is described in DE-A-2013763 described as well and can by known stabilizing agents for hydrogen peroxide still increased become. For many applications, for example as an additive to cleaning agents, is the necessary Long-term stability however not given. Another disadvantage is the relatively high Hydrophobic silica content.

task The invention is mixtures of silicon dioxide powder and hydrogen peroxide to provide, which have a long-term stability, which is higher than that of the prior art. Because of economic considerations the mixtures should also have the lowest possible proportion Have silicon dioxide.

The Task is solved through a powder Mixture containing hydrogen peroxide and hydrophobic, pyrogenic produced silicon dioxide powder, which is characterized is that the hydrophobized silica powder has methanol wettability of at least 40 and less than 9% by weight on the total weight in the mixture and the proportion of hydrogen peroxide, based on the total weight, is between 10 and 50 wt .-%.

The Methanol wettability gives the degree of hydrophobicity of the silica powder again. For this purpose, a certain amount of silicon dioxide powder is added Weighed in water. The silicon dioxide powder remains on the Surface. The methanol concentration required for wetting the powder is now determined. The Methanol wettability is the methanol content of a methanol-water mixture in% by volume, with 50% of the hydrophobized silicon dioxide sediment.

It it has now been found that hydrophobized silicon dioxide powder with a methanol wettability of more than 40 to particularly stable storage Mix with hydrogen peroxide, which have a hydrogen peroxide content between 10 and 50% by weight. Furthermore, a portion of these already leads hydrophobized silica powder of less than 9 wt .-%, based on the total mixture, to create a free-flowing powder.

On the invention further relates to a method for the production the powdery mixture according to the invention, which is characterized in that hydrophobized silicon dioxide powder with a methanol wettability of more than 40 at temperatures of not more than 70 ° C treated with an aqueous hydrogen peroxide solution becomes.

Suitable is every mixing element that has sufficient energy in the System made of water-repellent silicon dioxide powder hydrogen peroxide solution introduces to rapid breakdown of the liquid into small droplets guarantee, which was then immediately surrounded by the hydrophobized silicon dioxide powder become.

The hydrophobicized silica powder to be used are not limited as long as they have a methanol wettability of at least 40 have. Can prefer those with octamethylcyclotetrasiloxane, polydimethylsiloxane, octylsilane and / or hexamethyldisilazane hydrophobized silica powder be used.

The specific surface area of the hydrophobicized silicon dioxide powder to be used is likewise not limited. Those with a specific surface area of between 10 and 400 and particularly preferably those of 80 to 300 m ² / g can preferably be used.

Examples Such hydrophobized silicon dioxide powder can be found in Table 1.

Table 1: Hydrophobicized silicon dioxide powders, suitable for producing the powder mixture according to the invention

Hydrogen peroxide is used as an aqueous solution, preferably with a proportion of hydrogen peroxide between 5 and 70% by weight. Solutions with an H ₂ O ₂ content of 35 and 50% by weight are usually used.

advantageously, are the solutions stabilized against decomposition. Type and amount of stabilizer (s) hangs in primarily from the proportion of hydrogen peroxide in the aqueous solution from.

It is also possible solutions use to produce the powder mixture according to the invention, that are not stabilized. In these cases, the powder must have lower stability can be expected. Suitable stabilizers are stannates, phosphates, Pyrophosphates, nitrates, magnesium salts, phosphonic acids, aminophosphonic acids, EDTA, Gelatin and mixtures thereof, in amounts between 0.01 and 1% by weight be added.

On the invention furthermore relates to the use of the powder mixture according to the invention in Detergents, in cleaning agents, as well as in hair and skin treatment agents.

The Powder mixtures according to the invention can can be used as a bleaching component in detergents. Appropriate Detergents are known to the person skilled in the art from the prior art with inorganic Peroxygen compounds, such as sodium perborate or Sodium carbonate perhydrate, known. When using the invention in detergents and cleaning agents are preferably the inorganic Peroxygen compounds in whole or in part through the powder mixture according to the invention replaced.

The Powder mixtures according to the invention can as a bleaching component or germicidal Component used in detergents. Preferably be the powder mixtures according to the invention used in detergents without the addition of water for cleaning be applied. Examples of such Cleaning agents are stain removers for textiles, upholstery, carpets and carpets, which are used without the addition of water, for example in powder form become. Unlike inorganic peroxygen compounds, such as sodium perborate or sodium carbonate perhydrate, can the powder mixtures according to the invention in such cleaning agents their bleaching and germicidal effects even without adding water.

The powder mixtures according to the invention can be used as bleaching components in hair treatment agents can be used to bleach hair. The powder mixtures according to the invention are preferably added to such bleaching agents in amounts of 20 to 80% by weight. The bleaching agents also contain at least one alkaline component, preferably selected from hydroxides, carbonates, hydrogen carbonates and silicates of alkali or alkaline earth metals. The bleaching agent preferably contains the alkaline component in an amount of 10 to 40% by weight. The bleaching agents preferably also contain one or more surfactants, both nonionic and anionic, cationic or zwitterionic surfactants being suitable. Excipients. In addition, the bleaching agents can also contain other auxiliaries, such as, for example, nonionic, anionic or cationic polymers, thickeners, protein hydrolyzates, phospholipids, metal complexing agents, dyes and perfume oils. Corresponding bleaching agents are known to the person skilled in the art from the prior art, for example from WO 01/45658, with peroxodisulfates or other inorganic peroxides as the bleaching component. When used in bleaching agents according to the invention, the peroxodisulfates are preferably completely or partially replaced by the powder mixture according to the invention.

The powder mixtures according to the invention can furthermore be used as oxidizing agents in hair treatment agents for permanent dyeing of hair with oxidizing dyes. In this case, the powder mixtures according to the invention are mixed with a preparation containing the precursors developer component and coupling component for the oxidation dye shortly before the hair dye is used. The powder mixtures according to the invention can be mixed directly with the preparation of the dye precursors or previously dispersed in an aqueous solution or emulsion. An aqueous emulsion is preferably used as preparation of the dye precursors which, in addition to a developer component and coupling component for the formation of the dye, also contains one or more emulsifiers and one or more liquid nonpolar components and, if appropriate, further auxiliaries. Appropriate preparations of the dye precursors are known to the person skilled in the art, for example from DE 199 01 886 , known for use with liquid hydrogen peroxide preparations. When used in hair dyes according to the invention, the liquid hydrogen peroxide is preferably completely or partially replaced by the powder mixture according to the invention.

The Powder mixtures according to the invention can continue to be used as an oxidizing agent in skin treatment agents Used for purposes such as for skin lightening and removal of pigment spots and freckles.

Appropriate Skin treatment agents are known to the person skilled in the art from the prior art with inorganic peroxides, such as zinc peroxide or urea peroxide, organic peroxides, hydroquinone or basic bismuth salts as Active ingredients known. When used in skin treatment compositions according to the invention becomes the powder mixture according to the invention instead of these active ingredients or in addition to one or more of these active ingredients used.

The powder mixture according to the invention can also for the manufacture of skin disinfectants and agents used to treat acne or sporeasis. Appropriate Agents for treating acne or sporeasis are known to the person skilled in the art from the prior art with organic peroxides, such as Benzoyl peroxide, known as an active ingredient. In the use according to the invention Manufacture of agents to treat acne or sporeasis the powder mixture according to the invention used instead of the organic peroxide.

The powder mixture according to the invention can finally also as a hardener for the hardening of radically curable Preparations are used. Examples of such radically curable Preparations are resins, lacquers and adhesives based on vinyl ester resins, unsaturated Polyester resins or crosslinkable silicones. Appropriate radical curable Preparations are known to the person skilled in the art for curing known organic peroxides. When using the invention for the hardening of radically curable The powder mixture according to the invention is used instead of preparations of an organic peroxide used. The use of the powder mixture according to the invention Instead of organic peroxides has the advantage that the properties the hardened Products not adversely affected by organic peroxide fission products affected such as, for example, through odor development or discoloration of the Product.

Examples analysis methods

Determination of methanol wettability:

Weigh 0.2 g (± 0.005 g) of hydrophobic silicon dioxide powder into transparent centrifuge tubes. 8.0 ml of a methanol / water mixture with 10, 20, 30, 40, 50, 60, 70 and 80 vol .-% methanol are added to each sample. The sealed tubes are shaken for 30 seconds and then centrifuged for 5 minutes at 2500 min ^-1. The sediment volumes are read, converted into percent and plotted against the methanol content (vol.%). The turning point of the curve corresponds to the wettability of methanol.

Determination of the hydrogen peroxide content:

hydrogen peroxide is reduced by iron (II) sulfate in sulfuric acid solution. The surplus Iron (II) sulfate is back-titrated with potassium permanganate solution. The titration will from a Titroprocessor 682 with sample changer from Metrohm controlled.

Execution:

Approx. 0.6500-0.7000 g of a powder mixture of hydrogen peroxide and hydrophobized silicon dioxide are acidified with 25 ml of 25 percent sulfuric acid. 10 ml of an iron (II) sulfate solution (69.5 g / l iron (II) sulfate heptahydrate) are then pipetted in and then 50 ml of demineralized water are added. The mixture is mixed thoroughly with a propeller stirrer for 15 minutes and then titrated with KMnO ₄ solution (0.05 molar). The end point of the titration is determined potentiometrically. The blank value is the consumption of KMnO ₄ solution for the amount of iron (II) sulfate solution used.

Calculation:

Example 1:

It 93 g of a 10 percent hydrogen peroxide solution (stabilized commercially) with 7 g Aerosil 812 S in a multimixer (Braun, model MX 32) at the highest Level mixed 45 seconds. The high shear forces of the mixer break it up liquid in small droplets, which are enclosed by hydrophobic Aerosil. The resulting one Mixture is a free flowing one Powder.

The Examples 2 to 4 were carried out analogously and give powders according to the invention.

The Examples 5 to 7 represent comparative examples.

In Table 2 shows the starting materials and properties of powder mixtures listed with hydrogen peroxide and hydrophobized silicon dioxide.

The Examples 1 to 4 show that when using a hydrophobized Silicon dioxide powder with a methanol wettability of at least 40 even at very low levels of 7 and 5% by weight of free-flowing powder with high stability be preserved. Examples 6 and 7 show that when using hydrophobicized silica powders with a methanol ignitability less than 40 either no free flowing powder is obtained.

In Example 5 is indeed a free-flowing powder with a hydrophobized Silicon dioxide powder with a methanol wettability of less obtained as 40, but here too the stability of the hydrogen peroxide is less.

Examples 8 and 9:

use in a hair treatment agent for bleaching hair.

Table 3: Composition of the bleaching powder and the associated hydrogen peroxide developer solutions in% by weight

The Ingredients of the bleaching powder were in the proportions listed in Table 3 in weighed into a 1000 ml glass jar (Total batch: 500 g). After closing the glass jar the components in a free fall mixer (Turbula, Bachofen) gentle at 42 rpm for Mixed for 10 min. The developer solution (Total amount also 500 g) was prepared by adding water in submitted to a cleaned glass jar and hydrogen peroxide, phosphoric acid and acetanilide in the proportions of Table 3 with stirring were added with a glass rod.

Bleaching Powder and developer solution were in proportion Mixed 1: 1. Each 2.0 g of this mixture was dark blonde to 0.5 g strands of hair (Fischbach + Miller, code 6923). After 30 minutes of exposure the mixture was rinsed out of the strands of hair that Hair at 40 ° C for 2 h dried in a drying cabinet and then visually assessed. The with the mixture from Example 8 bleached hair was clear lighter than those treated with the mixture from Comparative Example 9.

Examples 10 and 11:

Use in a hair treatment product for coloring of hair.

To produce the coloring cream, 395.0 g deionized water and 35.0 g aqueous 25% by weight ammonia solution were used in a 3 l Stephan mixer (Stephan UMC 5 electronic, A. Stephan und Söhne GmbH & Co., Hameln, Germany) submitted. All other ingredients were added in the proportions of Table 4 and slowly mixed in. The mixture was then homogenized at 1000 rpm for 10 min, so that a uniform cream resulted, which was then filled into a well-cleaned 1 liter glass bottle with a screw cap. To prepare the developer emulsion, 442.5 g of water were placed in the cleaned Stephan mixer and all other components were added in the proportions of Table 4 with slow stirring. This mixture was then mixed at 50 rpm for 15 min until a homogeneous, slightly viscous mass had formed. This was turned into a well done nigt 1 l glass bottle filled with screw cap.

The coloring cream and developer emulsion were mixed in a 1: 1 ratio immediately before use mixed. Each 2.0 g of this mixture was dark blonde to 0.5 g strands of hair (Fischbach + Miller, code 6923). After a period of development The mixture was rinsed for 25 min, the hair at 40 ° C. for 2 h dried in a drying cabinet and then visually assessed. Both Lead mixtures to a light copper tone, the mixture from Example 10 a stronger one Hue led. Moreover it was significantly more viscous and therefore easier to apply than that from comparative example 11.

Table 4: Composition of the coloring cream and the associated developer emulsion in% by weight

Examples 12 and 13:

use in skin treatment products for the cosmetic treatment of acne.

to The acne gel from Example 12 was produced in a Stephan mixer Submitted ethanol. The other components were shown in the table 5 specified ratio added with slow stirring (Total batch: 500 g) and then gently at 50 rpm for 15 homogenized min.

Table 5: Composition of a gel-like skin treatment agent in% by weight

The Acne cream of Example 13 was made by adding to that in one Stephanmischer presented lipophilic cream base (German Pharmaceutical Code, New Prescription Form 1999, 16th Supplement, NRF 11.104, Govi publishing house, Deutscher Apotheker-Verlag) all other components in the in Table 6 specified proportions with slow stirring were added (total batch: 500 g) and the resulting mixture subsequently was gently homogenized at 50 rpm for 15 min.

Table 6: Composition of a skin treatment agent in the form of a cream in% by weight

Example 14:

Use in a powder detergent.

Table 7: Composition of a powder detergent in% by weight

Example 15:

Use to harden a unsaturated Polyester resin.

62 Parts by weight of Palatal A 410-01 (unsaturated polyester resin) with 1.7 parts by weight of pyrogenic silica (AEROSIL 200). Subsequently 18 parts by weight of styrene are added. As a bleeding additive 0.5 parts by weight of BYK-A 555 are then mixed in. Last becomes 1 part by weight of the powder mixture according to the invention for crosslinking added from example 2. The mixture hardens thereafter without discoloration Completely by.

Claims (9)

Powdery mixture containing hydrogen peroxide and hydrophobized, pyrogenically prepared silicon dioxide powder, characterized in that the hydrophobized silicon dioxide powder has a methanol wettability of at least 40 and is less than 9% by weight, based on the total weight, and the proportion of hydrogen peroxide, based on the Total weight, is between 10 and 50 wt .-%. Process for the preparation of the powdery mixture according to claim 1, characterized in that hydrophobized silicon dioxide powder with a methanol wettability of more than 40 at temperatures of not more than 70 ° C with an aqueous hydrogen peroxide solution is treated. A method according to claim 2, characterized in that as a hydrophobized silicon dioxide powder with octamethylcyclotetrasiloxane, Polydimethylsiloxane, octylsilane and / or hexamethyldisilazane hydrophobized Silicon dioxide powder is used. Method according to claims 2 or 3, characterized in that the specific surface is between 90 and 400 m ² / g. Method according to claims 2 to 4, characterized in that that the watery hydrogen peroxide solution has a proportion of hydrogen peroxide between 5 and 70 wt .-%. A method according to claim 5, characterized in that the watery Hydrogen peroxide solution stabilized is. Use of the powdery mixture according to claim 1 in detergents, cleaning agents and in skin and hair treatment products. Use of the powdery mixture according to claim 1 for the manufacture of agents for the treatment of acne. Use of the powdery mixture according to claim 1 as hardener for the hardening of radically curable Preparations, in particular for the hardening of vinyl ester resins, unsaturated Polyester resins or crosslinkable silicones.