WO2002030376A1

WO2002030376A1 - Dental cleaning agents

Info

Publication number: WO2002030376A1
Application number: PCT/EP2001/011196
Authority: WO
Inventors: Wolf Eisfeld; Angela Brands; Amerigo Pastura; Peter Wülknitz
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 2000-10-07
Filing date: 2001-09-27
Publication date: 2002-04-18
Also published as: AU2002220572A1; DE10049656A1; EP1326581A1

Abstract

The invention relates to aqueous dental cleaning agents consisting of particulate polishing agent components, humectants and surfactants. The surfactants contain a combination of anionic surfactants (A), non-ionic surfactants (N) and vegetable protein hydrolysates or their fatty acid (C12-C22) condensates. The anionic and non-ionic surfactants are preferably present in the weight ratio (A): (N) = 1: (0.2-2.0) and in a quantity of (A+N) = 1-3 wt.- %, in relation to the total weight of the dental cleaning agent, the protein hydrolysates or their fatty acid condensates in a quantity of 0.5-2.0 wt.- %, in relation to the total weight of the dental cleaning agent and in addition a betaine tenside in a quantity of 0.1-1.0 wt.- %, in relation to the total weight of the dental cleaning agent.

Description

"Dentifrice"

The invention relates to tooth cleaning agents in the form of an aqueous, pasty or liquid dispersion, containing particulate polishing agent components, humectants, surfactants and a vegetable protein hydrolyzate or one of its fatty acid (C ₂ -C ₂₂ ) condensation products, and the use of these tooth cleaning agents to improve the foaming power.

Toothpastes, toothpastes and tooth gels are used in the daily cleaning of the teeth by brushing with a toothbrush. The tooth cleaning agents are primarily intended to clean the tooth surface from food residues, discolourations caused by e.g. As tobacco or tea and support from the firmly adhering bacterial plaque, the so-called plaque. This happens on the one hand through the mechanical action of the brush and the polishing agent components, on the other hand through the surfactant and dispersing action of the surfactants. In addition, the surfactants are said to produce a certain foam that distributes the components of the toothpaste evenly in the mouth while brushing the teeth and also gives the user a pleasant mouthfeel. The consistency of the foam formed when brushing your teeth is an important factor for product acceptance. If the foam liquefies too quickly, it drips out of the mouth prematurely, which is perceived as unpleasant and leads to toothbrushing being stopped prematurely. On the other hand, it would make sense from a dental point of view to extend brushing over a period of at least three minutes.

The problem of too little and too little consistent foam when brushing teeth is particularly evident with semi-liquid tooth cleaning agents, which are often also transparent or clearly formulated and which contain a high proportion of humectants. The most obvious solution to the problem would be to increase the surfactant concentration. However, it has been shown that this measure only leads to a moderate improvement in the foaming power. On the other hand, there is an increase in concentration z. B. the foam-strong anionic surfactants set narrow limits for dermatological and taste reasons.

It was known from EP 0 036 439 B1 that gelatin hydrolyzate can significantly increase the foaming power of toothpastes containing surfactants. From DE 35 28 168 C1, protein hydrolysates of vegetable provenance were known which cause good foaming in the presence of small amounts of surfactants. N-acyiated amino acid mixtures based on cereal protein hydrolyzates were known from 0 586 501 B1, which are particularly suitable for cosmetic applications because of their lighter color and better transparency.

However, the toothpastes known from the prior art are not yet satisfactory in terms of their foam development and foam stability.

It has now been found that the foaming power of such tooth cleaning agents can be increased considerably if a combination of anionic surfactants, nonionic surfactants and vegetable protein hydrolyzates or their fatty acid condensation products is present as the surfactant component.

A first subject of the invention are aqueous tooth cleaning agents containing particulate polishing agent components, humectants and surfactants, which as surfactants are a combination of anionic surfactants (A), nonionic surfactants (N) and vegetable protein hydrolyzates or one of their fatty acids (C ₁₂ -C ₂₂ ) - Contain condensation products.

The dentifrices according to the invention have a significantly higher foaming power than corresponding compositions which contain an anionic, zwitterionic or nonionic surfactant instead of the protein hydrolyzate or its fatty acid condensate.

All known particulate polishing agents, but preferably precipitated and gel silicic acids, aluminum hydroxide, aluminum oxide, calcium pyrophosphate, calcium hydrogen phosphate, chalk, hydroxyapatite, sodium aluminum silicate (e.g. zeolite A) or organic polymers, e.g. B. polymethacrylates can be used. In a preferred embodiment of the invention, silicic acid polishing agents are contained as polishing agent components.

Suitable silica polishing components are all gel silicas, hydrogel silicas and precipitated silicas known as cleaning bodies. Gel silicas are produced by reacting sodium silicate solutions with strong, aqueous mineral acids to form a hydrosol, aging to the hydrogel, washing and drying. If the drying is carried out under gentle conditions to water contents of 15 to 35 wt .-%, the so-called hydrogel silicas are obtained, such as z. B. are known from US 4,153,680. Drying to water contents below 15% by weight results in an irreversible shrinkage of the previously loose structure of the hydrogel to form the dense structure of the so-called xerogel. Such xerogel silicas are e.g. B. described in US 3,538,230.

A second, preferably suitable group of silicic acid polishing agents are the precipitated silicas. These are obtained by precipitating silica from dilute alkali silicate solutions by adding strong acids under conditions in which the aggregation to the sol and gel cannot occur. Suitable processes for the preparation of precipitated silicas are e.g. B. in DE-OS 25 22 486 and described in DE-OS 31 14493. A precipitated silica prepared according to DE-OS 31 14 493 with a BET surface area of 15-110 m ² / g and a particle size of 0.5-20 μm is particularly suitable, with at least 80% by weight of the primary particles being below 5 μm , and a viscosity in 30% glycerol-water (1: 1) dispersion of 30 - 60 Pa s (20 ° C, measured with: Brookfileld viscometer RVF, Helipath, spindle, TE 4 rpm, after 1 hour) in an amount of 10-20% by weight of the tooth gel. Particularly suitable precipitated silicas of this type have rounded corners and edges and are under the tradename ^® Sident 12 DS (DEGUSSA). Another suitable silica is Zeodent 113 (Huber Corp) with a BET surface area of 150-250 m ² / g.

Other precipitated silicas of this type are Sident 8 (DEGUSSA) and Sorbosil AC 39 (Crosfield Chemicals). These silicas are characterized by a lower thickening effect and a somewhat higher average particle size of 8-14 μm with a specific surface area of 40-75 m ² / g (according to BET) and are particularly suitable for liquid tooth gels according to the present invention. Glycerin, sorbitol, xylitol, propylene glycol, polyethylene glycol or mixtures of these substances can be used as humectants. Preferred polyethylene glycols are those with average molecular weights from 200 to 2000.

Preferred anionic surfactants (A) are the readily water-soluble, strongly foaming primary linear (C ₁₂ -C ₁₈ ) alkyl sulfates, the linear C ₁₂ -C ₁₈ alkane sulfonates or alpha-olefin sulfonates, sulfosuccinic acid mono (C ₁₂ -C ₈ ) alkyl esters Salts, sulfoacetic acid (C ₁₂ -C ₁₈ ) alkyl ester salts, 2-hydroxyethanesulfonic acid (C ₁₂ -C ₁₈ ) alkyl esters (acyl isethionates), fatty acid (C ₁₂ -C ₁₈ ) monoglyceride sulfates, C ₁₂ -C ₁₈ -AcyIsarkoside- or Acyl- tauride, each in the form of their water-soluble alkali salts, in particular the sodium salts. The linear C ₂ -C ₁₈ alkyl sulfates, especially sodium lauryl sulfate, play a preferred role.

In principle, all water-soluble surfactants which preferably have a linear alkyl or acyl group with 12-18 C atoms and a polyol or polyether group which causes water solubility can be used as nonionic surfactants (N). Such surfactants are e.g. B. the adducts of ethylene oxide with fatty alcohols, with fatty acids, with fatty acid alkanolamides, with fatty acid monoglycerides, with fatty acid diglycerides, with castor oil with sorbitan mono fatty acid esters or with methyl glycoside mono fatty acid esters. Other suitable nonionic surfactants are the linear alkyl (C ₈ -C ₁₆ ) glucosides and alkyl (C ₈ -C ₁₆ ) oligoglucosides and their ethylene oxide addition products. The water solubility of the ethylene oxide adducts can be increased by the amount of the added ethylene oxide; it should be at least so high that 1% by weight of the surfactant dissolves in water at 20.degree.

Suitable vegetable protein hydrolyzates are all protein degradation products obtainable from vegetable proteins by hydrolytic degradation, which can also be catalyzed enzymatically. However, the hydrolysis should preferably not take place up to an amino acid mixture, but only to such an extent that sufficient clear solubility in water is achieved. The water solubility should be at least so high that 1% by weight of the protein hydrolyzate clearly dissolves in water at 20 ° C. Such protein hydrolyzates predominantly contain oligo- and polypeptide molecules in the molecular weight range from 1000 to 10000 D, preferably from 3000 to 5000 D, preferably in the form of their sodium salts. Suitable vegetable starting materials for producing protein hydrolyzates suitable according to the invention are e.g. B. cereals (wheat, oats, rice), nuts (almonds), legumes (beans, peas, soybeans) and algae. For example, hydrolysates of wheat protein (Gluadin ^® W 20, W 40), rice protein (Gluadin ^® R), almond protein (Gluadin ^® Almond), pea protein (Gluadin ^® P) and soy protein (Hydrosoy ^® 2000) are commercially available.

Fatty acid (C- ₂ -C ₈ ) condensation products of vegetable protein hydrolyzates are commercially available, e.g. B. the coconut fatty acid condensate of the wheat protein hydrolyzate in the form of the sodium salt as Gluadin ^® WK (sodium cocoyl hydrolyzed wheat protein), the coconut fatty acid condensate of the soy protein hydrolyzate as Proteol ^® VS22 (sodium cocoyl hydrolyzed soy protein) and the coconut fatty acid protein condensation product as Proteol ^® OAT

In a preferred embodiment of the invention, the non-peptide anionic and nonionic surfactants are in a weight ratio of (A): (N) = 1: (0.2-2) and in a total amount of (A + N ) = 1 - 3 wt .-%, based on the total weight of the dentifrice, and the vegetable protein hydrolyzate or its fatty acid (C ₁₂ -C ₂₂ ) condensation product in an amount of 0.5 - 2 wt .-%, based on the total weight of the dentifrice.

A further increase in the foaming power is achieved in that the aqueous tooth cleaning agent according to the invention additionally contains a betaine surfactant.

The betaine surfactant is preferably present in the tooth cleaning agents according to the invention in an amount of 0.1-1% by weight.

All readily water-soluble surfactants which have a zwitterionic structure with the element are suitable as betaine surfactants (B)

⁺ > (-)

-N-CH -COO exhibit. Suitable betaine surfactants are in particular N- (C ₁₂ -C ₁₈ ) -alkyldimethyl-aceto-betaine and N- (C ₁₂ -C ₁₈ ) -acylaminopropylacetobetaine (cocoamidopropyl-betaines).

As already explained above, the dentifrices according to the invention can also be formulated as liquid or semi-liquid dispersions with viscosities (at 20 ° C.) of 5-100 Pa s. For this purpose, it is necessary to limit the content of polishing components and to avoid thickening silicas.

In a preferred embodiment, the aqueous tooth cleaning agent according to the invention contains silicas as the polishing component.

The silica component is preferably used in an amount of 8-20% by weight, in particular in an amount of 10-15% by weight, based on the total weight of the dentifrice.

Furthermore, a component selected from sorbitol, glycerol, propylene glycol, polyethylene glycol and mixtures thereof is preferably used in the agents according to the invention as a humectant.

The humectant is particularly preferably used in an amount of 40-70% by weight, based on the total weight of the dentifrice.

The aqueous dentifrices according to the invention can also be formulated as transparent or clear gels. For this purpose it is necessary that the carrier mixture of water and humectants has a refractive index that differs as little as possible from the refractive index of the polishing agent. If silica polishing agents are used, this can generally be achieved by means of a humectant content of 40-60% by weight and a weight ratio of humectant to water of (1.5-2.5): 1. It is preferred that at least half of the humectant consists of sorbitol and that a polyethylene glycol with a molecular weight of 200-2000 is contained in an amount of 1-5% by weight.

In addition to the compulsory components mentioned, the dentifrices according to the invention can contain further conventional ingredients and auxiliaries and additives which increase the therapeutic or oral hygiene value or improve the organoleptic and application properties. Such other ingredients are e.g. B. active substances against tooth and gum diseases, for example fluorine compounds such as sodium fluoride, zinc fluoride and sodium monofluorophosphate, anti-tartar active substances (e.g. polyphosphates,

Hydroxyethane diphosphonates, azacycloheptane diphosphonate), antimicrobial substances (e.g. biguanides, chlorhexidine, triciosan), vitamins (e.g. tocopherol, retinol), panthenol, plant and algae extracts as well as wound healing and anti-inflammatory substances such as. B. urea, allantoin, azulene, Rhödanide, magnesium salts.

As auxiliaries and additives such. B. be included

Binders such as B. natural and / or synthetic water-soluble polymers such as alginates, carragheenates, tragacanth, starch and starch ethers, cellulose ethers, such as. B. carboxymethyl cellulose. Hydroxyethyl cellulose, methyl hydroxypropyl cellulose, guar, acacia gum, agar agar, xanthan gum, succinoglucan gum, locust bean gum, pectins, water-soluble carboxyvinyl polymers (Carbopol ^® ), polyvinyl alcohol, polyvinylpyrrolidone and polyethylene glycols with molecular weights from 2000 to 50000.

Flavors, e.g. B. flavors such as peppermint oil, spearmint oil, eucalyptus oil, anise oil, fennel oil, caraway oil, menthyl acetate, cinnamaldehyde, anethole, vanillin, thymol and other natural or nature-identical oils or synthetic flavors.

Sweeteners such as B. saccharin sodium, sodium cyclamate, acesulfame, aspartame, sterioxide, thaumatin, glycyrrhicin, sucrose, lactose, maltose or fructose.

Preservatives, such as B. p-hydroxybenzoic acid ester, sodium benzoate, sodium sorbate

Buffer substances, such as. B. primary, secondary and tertiary alkali phosphates, citric acid / sodium citrate

Remineralizing salts such as e.g. As calcium dihydrogen phosphate, magnesium, zinc or manganese salts

Dyes and / or pigments Another object of the invention is the use of the tooth cleaning agents according to the invention to improve the foaming power.

The following examples are intended to explain the subject of the invention in more detail:

Examples

Testing the foam properties of toothpastes

1. Test methodology

To compare the foam properties of dentifrices, a toothbrush simulator was used, which is structured as follows:

A toothbrush is attached to a pneumatically operated linear feed, which is positioned with variable pressure on a wave profile made of steel cylinders. The travel distance per stroke is 11 cm. The wave profile was designed based on different requirements (abrasion resistance, regular spacing, no steep edges, easy cleaning after the tests) and is based on the natural profile of the teeth in the mouth. In addition, it is removable to make cleaning easier. The height adjustment of the toothbrush, which regulates the pressure of the brush on the wave profile, can be locked. Within a cleaning time of 60s, 2ml of water are continuously added via a peristaltic pump. The water is dropped directly next to the brush head. The apparatus can be controlled with a switch box in terms of the number of movements or over a defined period of time. The speed can also be set on the pneumatic cylinder. This offers different options for experiment design. In the test series described, for example, 16 strokes correspond to a time period of 10 s.

The tests were carried out as follows:

First, 1g of product is metered onto the wave profile over a distance of 3.5 cm, then the profile plate is inserted into the machine, the moistened toothbrush is placed on with light pressure and the first image without foam is taken as a reference (O-image). After starting the machine, 16 back and forth movements of the toothbrush (ie 8x back and 8x back; duration total 10s) are carried out. After stopping the movement, the next picture is taken, etc. This process is repeated five more times until a total of 60s cleaning time is reached. As already described, a total amount of water of 2 ml is continuously metered in during the entire cleaning period. After completing this foam generation process, an image is taken every minute for 5 minutes to document the foam stability. 2. Evaluation:

On all images, algorithms of digital image processing detect the bright area generated by the foam and set it as a percentage in relation to the entire measuring area. The proportion of area determined in each case in the O-picture is subtracted from all the following measured values, since a) no foam has yet been generated and bright areas are therefore only artifacts and b) in order to achieve standardization to uniform initial values.

In Table I, the percentages by area of the foam after 60 seconds and after 5 minutes are given as foam (60 sec) and foam (5 min).

3. Implementation

Eight toothpastes, which differ only in the composition of the characteristic components, were subjected to a comparative test.

The comparison pastes Va, Vb, Vc and Vd contain no protein hydrolyzate.

The comparison pastes Vb, Vc and Vd contain increased amounts of the anionic, betaine and nonionic surfactant. Pastes 1-4 according to the invention contain vegetable protein hydrolyzates or a vegetable protein hydrolyzate fatty acid condensation product.

The toothpastes 1 to 4 according to the invention have a significantly higher foaming power and foam stability.

The composition of the toothpastes and the results of the foam measurements can be found in the table. Unless otherwise stated, the amounts of the components relate to anhydrous active substance in g. Table 1

The following commercial products were used:

Claims

claims

1. Aqueous tooth cleaning agents containing particulate polishing components, humectants and surfactants, which contain as surfactants a combination of anionic surfactants (A), nonionic surfactants (N) and vegetable protein hydrolyzates or one of their fatty acid (C ₁₂ - C ₂₂ ) condensation products.

2. Aqueous tooth cleaning agent according to claim 1, characterized in that the anionic and nonionic surfactants in a weight ratio (A): (N) = 1: (0.2-2.0) and in an amount (A + N) of 1 -3 wt .-% o, based on the total weight of the dentifrice, are included.

3. Aqueous tooth cleaning agent according to one of claims 1 or 2, characterized in that the vegetable protein hydrolyzate or its fatty acid (Cι ₂ - C ₂₂ ) condensation product in an amount of 0.5-2 wt .-%, based on the total weight of the Dentifrices are included.

4. Aqueous tooth cleaning agent according to one of claims 1 to 3, characterized in that a beta-surfactant is additionally contained.

5. Aqueous tooth cleaning agent according to claim 4, characterized in that the betaine surfactant is contained in an amount of 0.1-1 wt .-%, based on the total weight of the tooth cleaning agent.

6. Aqueous tooth cleaning agent according to one of claims 1-5, characterized in that it contains at least one polishing component selected from the group of silicas.

7. Aqueous tooth cleaning agent according to claim 6, characterized in that the polishing component is contained in an amount of 10-15% by weight, based on the total weight of the tooth cleaning agent.

8. Aqueous tooth cleaning agent according to one of claims 1 to 5, characterized in that the humectant is selected from sorbitol, glycerin, polyethylene glycol and mixtures thereof.

9. Aqueous tooth cleaning agent according to claim 8, characterized in that the humectant is contained in an amount of 40-70 wt .-%, based on the total weight of the tooth cleaning agent.

10. Use of an aqueous tooth cleaning agent according to one of claims 1 to 9 to improve the foaming power.