NO154543B - TOOTHPASTE. - Google Patents

Description

The invention relates to a toothpaste to promote oral hygiene. In the past, toothpastes have been used which contain a single fluoridating agent, such as sodium fluoride, divalent stannous fluoride or sodium monofluorophosphate (it will be understood that a smaller proportion of commercial sodium monofluorophosphate comprises sodium fluoride).

Recently, e.g. in British patent specification 1435624 and

US Patent 4,152,419, toothpastes for promoting oral hygiene have been described as containing two separate to-

added fluorinating agents, i.e. sodium fluoride and sodium monofluorophosphate. However, toothpastes containing two such fluoridating agents and a siliceous polishing material comprising a small amount of combined aluminum oxide have not been disclosed.

The invention aims to provide a . toothpaste that contains sodium fluoride and sodium monofluorophosphate and that promotes oral hygiene, e.g. by reducing tooth decay and causing remineralization of the teeth.

The invention also aims to provide a toothpaste with a silicon dioxide-containing abrasive and with high fluoride stability.

The invention thus relates to an opaque toothpaste which is characterized by the fact that it comprises 0.5-2% by weight of an opacifying agent, a binary fluorinating system which provides 750-1225 ppm fluorine from sodium monofluorophosphate and 50-1000 ppm fluorine from separately added sodium fluoride, as it total amount of sodium fluoride is 0.01-0.2% by weight of separately added sodium fluoride and 0-0.015% by weight of sodium fluoride present as an impurity in the sodium monofluorophosphate, and 15-20% by weight of a polishing agent consisting essentially of a synthetic silicon dioxide which contains up to 1% by weight of aluminum oxide interlinked with this.

Sodium monofluorophosphate is used in an amount so that 750-1225 ppm fluoride is obtained in the toothpaste. This corresponds to 0.5-1% by weight of sodium monofluorophosphate in the toothpaste. The preferred amount is approx. 0.76% which gives approx. 1000 ppm fluoride in the toothpaste.

Sodium monofluorophosphate, Na^PO^F, of commercial quality can have a widely varying purity. It can be used with any suitable purity, provided that any contamination will not adversely affect the desired properties to a significant extent. Purity should generally be at least 80%. To achieve the best results, it should be at least 85% by weight, preferably at least 90% by weight,

sodium monofluorophosphate, with the rest mainly made up of impurities or by-products from manufacturing, such as sodium fluoride and water-soluble sodium phosphate salt. Expressed in another way, the sodium monofluorophosphate used should have a total fluoride content of more than 12%, preferably more than 12.7%, a content of not more than 1.5%, preferably not more than 1.2%, of free sodium fluoride and a sodium monofluorophosphate content of at least 12%, preferably at least 12.1%, always calculated as fluorine.

Sodium fluoride is added separately so that an additional amount of fluorine of 50-1000 ppm is obtained, e.g. 50-100 ppm. This corresponds to 0.01-0.2% sodium fluoride.

The polishing material is a synthetic, precipitated silicon dioxide that contains up to 1% by weight of aluminum oxide interlinked with it. Such polishing materials can also be considered aluminum silicates, especially sodium aluminum silicates. Typical examples are described in US patent documents 3906090, 4015996, 4105757 and 4122160. Commercially available grades of these materials are, for example, "ZEO 49" and "ZEO 49B" and Tixosil<®>53. The polishing agent is used in an amount of 15-20% by weight.

If desired, a smaller amount, such as 0.5-1.0%, of dicalcium phosphate may be present as an additional polishing agent.

The toothpaste according to the invention is opaque.

As the polishing agent is distinctive in that it has a refractive index that is close to the refractive index of wetting agents,

such as glycerol and sorbitol, which are typically used in toothpastes, 0.5-2% of an opacifying agent, such as titanium dioxide, is used

oxyd or an equivalent agent. The toothpaste typically contains 50-80% by weight humectant, e.g. 20-30% by weight

glycerol and 30-60% by weight sorbitol (70% solution).

Other opacifiers, such as zinc oxide, can be used in oral care acceptable amounts that do not adversely react with other ingredients in the toothpaste.

Water may also be present in small amounts, such as 2-7% by weight. If it is desired to color the toothpaste, coloring matter can be dissolved in the water.

The toothpaste also typically contains a gel agent, such as

the natural and synthetic rubber and rubber-like material, e.g. Irish moss, gum tragacanth, sodium carboxymethylcellulose, polyvinylpyrrolidone or starch.

Sodium carboxymethyl cellulose is preferred. The gel agent content is typically 0.1-5% by weight, preferably 0.1-0.5% by weight. The gel agent effect can be supplemented with 7-8% of a filler, such as pyrogenic silicon dioxide or a silicon dioxide airgel. Zeosyl 200" is a desired silicon dioxide filler.

Any surface-active or cleansing material can be used in the dentifrices. Such compatible materials are desired because they provide additional cleansing, foaming and antibacterial properties depending on the particular type of surfactant, and they are selected in a similar manner. These cleaning agents are usually water-soluble compounds and can have an anion-active, non-ionogenic or cation-active structure. It is generally preferred to use the water-soluble non-soap or synthetic organic cleaning agents. Suitable cleaning agents are known and include e.g. the water-soluble salts of higher fatty acid monoglyceride monosulfate (e.g. sodium coconut fatty acid monoglyceride monosulfate), higher alkyl sulfate (e.g. sodium lauryl sulfate), alkylarylsulfonate (e.g. sodium dodecylbenzenesulfonate) or higher fatty acid esters of 1,2-dihydroxypropanesulfonate etc.

Additional surfactants include the substantially saturated higher aliphatic acylamides of lower aliphatic aminocarboxylic acid compounds, such as those having 12-16 carbon atoms in the acyl radical. The amino acid part is generally derived from the lower aliphatic saturated mono-aminocarboxylic acids with 2-6 carbon atoms, usually the mono-carboxylic acid compounds. Suitable compounds are the fatty acid amides or glycine, sarcosine, alanine, 3-aminopropanoic acid or valine with 12-16 carbon atoms in the acyl group. However, it is preferred to use the N-lauroyl, N-myristoyl or N-palmitoylsarcoside compounds to achieve optimal effects.

The amide compounds can be used in the free form

acid or preferably ± form of the water-soluble salts thereof, such as the alkali metal, ammonium, amine or alkylol-amine salts. Particular examples of these are sodium and potassium N-lauroyl, myristoyl or palmitoyl sarcosides, ammonium or ethanolamine N-lauroyl sarcoside, N-lauroyl sarcosine or sodium N-lauroyl glycide or alanine.

The surfactant is typically used in a

amount of 1-5% by weight, preferably 1-3% by weight. Sodium lauryl sulfate is preferred.

Any suitable flavoring material or sweetener can be used to flavor the toothpaste according to the invention. Examples of suitable flavoring ingredients include the flavoring oils, e.g. oils of spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyptus, marjoram, cinnamon, lemon or orange, and also methyl salicylate. Suitable sweeteners include sucrose, lactose, maltose, sorbitol, sodium cyclamate or sodium saccharin. Sodium saccharin is preferred. The flavoring agent is typically present in an amount of 0.5-15% by weight, preferably approx. 1% by weight, and the sweetener in an amount of 0.1-0.2% by weight.

If desired, visible particles of mother-of-pearl-like flakes, such as mica flakes coated with titanium dioxide, can be distributed in the toothpaste, typically in an amount of 0.1-0.3% by weight. The toothpaste can also be striped.

The toothpaste can be filled in ordinary tubes, such as lined or unlined aluminum tubes or wax-lined lead tubes.

The toothpastes should have a pH that is practical for use.

A pH range of 5-10 is particularly desired. This reference to pH applies to pH as determined directly on the toothpaste.

The invention is described in more detail in the examples below. In these, all quantities are based on weight unless otherwise stated.

Example 1

The following toothpaste is produced in the usual way:

Example 2

A further toothpaste is prepared, again in the usual way, with the same composition as according to example 1, except that 0.25 parts of mica flakes coated with titanium dioxide are added and that the water content is lowered by the same amount.

Table 1 below shows compositions for three toothpastes that were produced in the usual way, of which the toothpaste indicated as example 3 is according to the invention. It appears that the toothpaste according to example 3 shows an increased fluoride level and an increased fluoride retention during the trial period compared to ordinary opaque toothpastes as exemplified by the comparison toothpastes A and B.

The fluorine content was determined by the standard method

which is described by Cropper and Puttnam^on page 533 of vol.21

(1970) of The Journal of the Society of Cosmetic Chemists of Great Britain.

Claims (2)

1. Opaque toothpaste, characterized in that it comprises 0.5-2.0% by weight of an opacifier, a binary fluorinating system which provides 750-1225 ppm fluorine from sodium monofluorophosphate and 50-1000 ppm fluorine from separately added sodium fluoride, the total amount of sodium fluoride being 0 .01-0.2% by weight of separately added sodium fluoride and 0-0.015% by weight of sodium fluoride present as an impurity in the sodium monofluorophosphate, and 15-20% by weight of a polishing agent consisting essentially of a synthetic silicon dioxide containing up to 1 weight % aluminum oxide mutually bound to this. 2. Toothpaste according to claim 1, characterized in that the separately added sodium fluoride gives 50-100 ppm fluorine.