JPH022858B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a dentifrice composition comprising sodium monofluorophosphate and an abrasive, at least a major portion of which is finely ground particles of dicalcium phosphate dihydrate. Sodium monofluorophosphate is recognized as an excellent dentifrice material for reducing caries formation.
Used in commercial toothpaste. Sodium monofluorophosphate has been clinically demonstrated to be helpful in reducing caries formation when used in combination with dicalcium phosphate dihydrate (abrasive) (Naylor and Emslie,
British Dental Journal, published July 4, 1967,
(pp. 17-23). A toothpaste containing sodium monofluorophosphate and dicalcium phosphate dihydrate is disclosed in U.S. Patent No. 3308029 (granted to Manahan et al.) and
No. 3,634,585 (to Saunders et al.) is the subject of the invention. As mentioned above, these toothpastes are effective in reducing tooth decay. However, it has been observed that when toothpaste containing sodium monofluorophosphate and dicalcium phosphate dihydrate is stored and allowed to age, the amount of F ^-1 retained becomes lower than the optimal value. The present invention provides a grade of dicalcium phosphate dihydrate that, in combination with sodium monofluorophosphate, exhibits higher fluorine retention than levels obtained using commercially available dicalcium phosphate dihydrate. is provided. Conventionally, since crude anhydrous dicalcium phosphate tends to damage tooth enamel, it has been proposed to use anhydrous dicalcium phosphate with a small particle size in tooth brushing. Pertinent disclosures are U.S. Pat.
No. 4169796 (to Dahlin). However, dicalcium phosphate dihydrate has significantly less tendency to damage tooth enamel than anhydrous dicalcium phosphate. Under these conditions, U.S. Pat.
There is no need to specifically classify the particle size distribution of the dihydrate using special methods such as those discussed in the '796 patent. It is an advantage of the present invention that high fluoride ion retention of toothpastes containing sodium monofluorophosphate and dicalcium phosphate dihydrate is achieved. Other advantages will be apparent from the description herein. In one aspect, the invention provides about 0.05 to about 7.6
% by weight of an abrasive compatible with sodium monofluorophosphate, at least a major portion of the abrasive having a total particle size greater than 3 microns;
The present invention relates to a dentifrice composition having a particle size in which at least about 65% of the total particles are between 3 and 10 microns in size or are dicalcium phosphate dihydrate. Sodium monofluorophosphate _{( Na2PO3F} )
is a water-soluble material that releases monofluorophosphate ions into water and can be mixed with the abrasive in any suitable amount. Such dental preparations are as follows:
Compatible with appropriate amounts of surfactants, gums, etc. Commercially available sodium monofluorophosphate varies considerably in purity. Any suitable purity can be used so long as the impurities do not materially adversely affect the desired properties.
Generally, purity will be at least about 80%. For best results, at least 85%, preferably at least 90% (both by weight) should be sodium monofluorophosphate, with the remainder primarily impurities or by-products, such as sodium fluoride, aqueous sodium phosphate. Salt, etc. Stated another way, the sodium monofluorophosphate used has a total fluorine content of about 12%, preferably about 12.7%, and a free sodium fluoride content of 1.5% or less, preferably 1.2% or less;
Sodium monofluorophosphate content is at least 12
% (calculated as fluorine). The proportion of sodium monofluorophosphate in toothpaste can be varied, but should be an effective, non-toxic amount containing more than 0.01% (100 ppm) fluoride. Suitable amounts are selected from within the range of about 0.05 to about 7.6% by weight. Preferably, the fluorophosphate sodium salt is present at most 2% by weight of the dentifrice, usually in the range of about 0.05-1%. If desired, the sodium monofluorophosphate can be mixed with another fluorine feedstock such as sodium fluoride, potassium fluoride, stannous fluoride, and the like. When mixed, the ratio of fluorine attributable to the monofluorophosphate to fluorine attributable to other fluorine salts is from about 9:1 to about 3:2. At least the main part of the abrasive (at least 50% by weight)
is finely divided dicalcium phosphate dihydrate. The typical grade of dicalcium phosphate dihydrate used in tooth brushing is
Technology,” edited by Balsam and Sagarin, 2nd edition, Volume 1, pages 477-479, where 60% of the particles are larger than 15 microns;
Commercial dicalcium phosphate of which 3% is larger than 35 microns is mentioned. american patent
No. 3,308,029 states that dicalcium phosphate dihydrate is ~200 mesh, corresponding to particles passing through a sieve with pores of 74 microns by 74 microns. Various grades of dicalcium phosphate dihydrate can be obtained by art-recognized techniques such as air fractionation, milling, milling, steam jet milling, and the like. The size used is at least 3 microns, at least about 65% of which, e.g.
65-100% are approximately 3-10 microns in size. A typical technique for reducing the size of dicalcium phosphate dihydrate particles and classifying particles with reduced size is as follows. Particle production takes place under the action of an air stream. A feedstock consisting of a mixture of particle sizes is dropped onto a horizontal distribution plate driven by a vertical shaft that also has fan blades. This plate disperses particles into the air stream,
A fan maintains air circulation within the separator. Air flows downward, then suddenly reverses and flows upward. Larger, heavier particles are less mobile and therefore do not travel with the air, but are thrown towards the inner surface of the inner cone where they are collected and collected. Smaller particles are carried by air into the annular space between the two cones (where the velocity is slow enough that the particles settle and are removed from the bottom of the outer cone). The physical separation method described above is called wind separation. Dicalcium phosphate dihydrate can be used as the sole abrasive or mixed with small amounts of one or more other dentally acceptable abrasives that do not have a materially negative effect on fluoride retention. Good too. Such additional abrasives include anhydrous dicalcium phosphate (the hydrated salt tends to partially dehydrate even when anhydrous dicalcium phosphate is not added separately), calcium carbonate, silica,
Calcined alumina, hydrated alumina, calcium pyrophosphate, tricalcium phosphate, calcium metaphosphate, etc. Typically, when additional abrasive material is present, the weight ratio of dicalcium phosphate to such additional material will be from about 99:1 to about 65:35, usually about
The ratio is 25:1 to 3:1. It is generally preferred to produce a dental cream containing 40-60% abrasive (with dicalcium phosphate as the main abrasive ingredient) and 1-15% calcium carbonate. If desired, suitable amounts of other abrasives such as alumina, calcium pyrophosphate, tricalcium phosphate, calcium polymetaphosphate, etc. can be added. The total content of abrasives is normal in toothpaste;
at least 20%, such as about 20-99%, especially 20-75
%, preferably 40-60%, and in toothpastes at least 70%. Any suitable surfactant or detergent can be included in the dentifrice composition of the present invention. Such compatible materials desirably provide additional cleaning, foaming, and antimicrobial properties depending on the particular surfactant and are similarly selected. The detergent is typically a water-soluble organic compound and may be anionic, nonionic, or cationic in structure. Water-soluble salts of higher fatty acid monoglyceride monosulfate (e.g. sodium coconut fatty acid monoglyceride monosulfate), higher alkyl sulfates (e.g. sodium lauryl sulfate), higher fatty acid esters of 1,2-dihydroxypropanesulfonate (e.g. 1,2
- Coconut fatty acid ester of sodium dihydroxypropanesulfonate) and the like are preferably used. Although various surfactants can be used in any suitable amount, they generally range from about 0.05% to about 10% by weight of the dentifrice composition.
Preferably, it can be used in amounts of about 0.5 to 5% by weight. Substantially saturated higher aliphatic acylamides of lower aliphatic aminocarboxylic acid compounds, such as those in which the acyl group has from 12 to 16 C atoms, more particularly in the U.S. patent issued September 14, 1954.
The one described in Publication No. 2689170 is extremely desirable.
The amino acid portion generally has a number of C atoms of about 2 to
6 lower aliphatic monoaminocarboxylic acids, usually monocarboxylic acid compounds.
Suitable compounds are fatty acid amines of glycine, sarcosine, alanine, 3-aminopropanoic acid, valine having about 12 to 16 C atoms in the acyl group.
Preferably, N-lauroyl myristoyl compounds and palmitoyl sarcoside compounds are used. The amide compounds can be used in the free acid form or, preferably, as their water-soluble salts, such as alkali metal, ammonium, amine, alkanoylamine salts. Specific examples thereof are sodium (or potassium) N-lauroyl (or myristoyl or palmitoyl) sarcoside, ammonium (or ethanolamine) N-lauroyl sarcoside (or N-lauroyl sarcosine) and sodium N-lauroylglyside (or alanide). ). For convenience, herein, "aminocarboxylic acid compound", "sarcoside", etc. refer to a compound having a free carboxyl group of a water-soluble carboxylate salt. Such materials may be utilized in pure or substantially pure form. They should be as free as possible from soaps and similar higher fatty acid substances which tend to reduce their activity. Typically, the amount of such higher fatty acid material will be less than 15% by weight of the amide and will not have a material adverse effect thereon, and preferably will be less than about 10% of the amide material. In accordance with the present invention, the specified combination of ingredients may be used in suitable formulations (referred to herein as dentifrice compositions) designed for oral use. Such toothpastes may be solid, liquid, or paste, and include toothpastes, dental creams, toothpastes, liquid toothpastes, tablets, and the like. Such products are manufactured in a conventional manner. In the manufacture of toothpaste, mechanical mixing of the various solid ingredients is usually sufficient. In formulating dental creams, the proportions of liquid and solids must be considered to form a creamy mass of the desired consistency that can be extruded from, for example, collapsible aluminum or lead tubes. Generally, the liquid in dental creams is primarily water, glycerin, sorbitol, propylene glycol (including appropriate mixtures thereof).
etc. It is usually advantageous to use a mixture of water and humectants or binders, such as glycerin, sorbitate or mixtures thereof. The total liquid level is generally about 20-75% by weight of the formulation. It is also preferable to use gelling agents in dental creams, such as natural or synthetic gums or gummy substances, such as iris gum, gum tragacanth, sodium carboxymethylcellulose, polyvinylpyrrolidone, starch, and the like. Iris moss and sodium carboxymethylcellulose are particularly compatible and preferred gelling agents. The gum content is usually up to about 10%, preferably about 0.5-5% of the weight of the formulation. Other types of dentifrice compositions may also be formulated in known manner. Small amounts of hydrated alumina oxide can be incorporated into dentifrice formulations. More specifically, dental creams with improved physical properties contain dicalcium phosphate dihydrate (a small amount of calcium carbonate or phosphoric anhydride) suspended in a gel consisting of water, a humectant, and a gelling agent. dicalcium), the monofluorophosphate compound and an organic non-soap synthetic detergent, and a small amount of hydrated aluminum oxide (preferably blended). These dental creams exhibit excellent long-term cosmetic properties and physical stability over time. In addition to being a minor abrasive, the aluminum oxide also acts as a stabilizer and modifier to reduce or prevent the tendency of the dental cream to separate or "ooze" within the collapsible tube. A suitable example of the hydrated aluminum oxide used is α-
It is also known as β-aluminum oxide trihydrate or a mixture thereof. It is usually used in the production of dental creams in the form of microparticles with the desired particle size. in fact,
At least about 90% of the weight is American standard No. 325
It is preferred to use an alpha hydrate that passes through a mesh sieve and has a particle distribution in which no more than about 5% are less than 5 microns. It has been found that an amount of hydrated aluminum oxide from about 1/4 to 10% by weight is most desirable. In order to adjust the physical properties of the composition, various Ca, Mg
Ionic suppressants can also be used. Suitable agents are water-soluble inorganic polyphosphates, such as tetrasodium pyrophosphate and disodium pyrophosphate diacid, with partially neutralized or acidic polyphosphates being preferred. Other suitable agents are alkali metal (preferably Na) salts of citric acid. in general,
Such compounds are a small amount or percentage of the formulation.
The exact amount will vary depending on the particular formulation, such as the physical properties of the resulting dental cream, but will usually range from about 0.1% to about 3% by weight. Various other materials can also be incorporated into the oral formulations of the present invention. Examples are coloring or whitening agents, preservatives, silicones, chlorophyll compounds, ammoniated substances such as urea or diammonium phosphate and mixtures thereof. These adjuvants are incorporated into the composition of the present invention in amounts that do not adversely affect its properties, but
It is appropriate to select and use appropriate amounts depending on the particular type of intended formulation. For some purposes, it may be desirable to include an antimicrobial agent in the compositions of the present invention. A representative antimicrobial agent that can be used in an amount of about 0.01 to about 5%, preferably about 0.05 to about 1.0%, by weight of the dentifrice composition is N'-4-(chlorobenzyl) ^-N5- (2,4-dichloro). benzyl) biguanide; p-chlorophenyl biguanide; 4-chlorobenzhydryl biguanide; 4-chlorobenzhydrylguanylurea; N-3-lauroxypropyl- ^N5 -p-chlorobenzyl biguanide; 1,6-di- p-chlorophenyl biguanidohexane; 1-(lauryldimethylammonium)-8-
(p-chlorobenzyl) dimethylammonium octane dichloride; 5,6-dichloro-2-guanidinobenzimidazole; 5-amino-1,3-bis(2-ethylhexyl)-5-methylhexahydropyridine; and their non-toxicity It is an acid addition salt. Any suitable flavoring or sweetening agent may be used in formulating the flavor of the compositions of this invention. Examples of suitable flavoring ingredients are flavoring oils such as spearmint oil, peppermint oil, wintergreen oil, satsafras oil, clove oil, sage oil, eucalyptus oil, marjoram oil,
Cinnamon oil, lemon oil, orange oil and methyl salicylate. Suitable sweetening agents are sucrose, lactose, maltose, sorbitate, sodium cyclamate, soluble saccharin, the dipeptides described in US Pat. No. 3,939,261, and the oxathiazine salts described in US Pat. No. 3,932,606. Suitably, the flavoring agents and sweeteners together make up from about 0.01 to 5% or more of the compositions of the present invention. Dental creams must have a practical pH. A PH range of 5 to 9 is particularly desirable. Herein PH
Values are measured directly with synthetic toothpaste. If desired, add ingredients like benzoic acid or citric acid to adjust the pH.
can be adjusted to, for example, 5.5 to 6.5. The dentifrice of the present invention is typically packaged in extruded tubes (typically made of lined aluminum or lead) or pressurized containers. The following specific examples further illustrate the nature of the invention and are not intended to limit the invention thereto. The compositions in the examples are prepared in conventional manner and all amounts of the various ingredients are by weight unless otherwise specified. EXAMPLE Dicalcium phosphate dihydrate, obtained as 240C DCPD from Monsanto, was split. One part was left as is, and another part was subjected to air separation to separate particles up to 3 microns in size (7% of the number of particles). The size specifications for 240C DCPD control grade are as follows:

[Table] Dicalcium phosphate dihydrate was blended into the following toothpaste composition in a conventional manner. Part glycerin 22.00 Soluble saccharin 0.20 Sodium carboxymethylcellulose 1.00 Sodium monofluorophosphate 0.76 Tetrasodium pyrophosphate 0.25 Dicalcium phosphate dihydrate 48.76 Sodium lauryl sulfate 1.50 Flavoring agent 1.00 Water 24.53 Each toothpaste was aged for 3 weeks at 49℃ The following results were observed regarding soluble fluorine, soluble monofluorophosphate (as fluorine), and fluorine ion after drying.

[Table] Large Based on these results, the fluorine retention rate of toothpaste containing sodium monofluorophosphate can be significantly improved by using dicalcium phosphate dihydrate, which excludes fine particles smaller than 3 microns. It is observed that. Approximately 65% of the particles in this grade are within the size range of approximately 3 to 10 microns. When 5 parts of calcium carbonate is used in place of 5 parts of the dicalcium phosphate dihydrate and 1 part of hydrated alumina is used in place of 1 part of the dicalcium phosphate dihydrate. Similarly, desirable results were obtained. Desirable results were also obtained using 0.05 parts of sodium monofluorophosphate and 0.06 parts of sodium fluoride. The above embodiments are merely illustrative, and it is natural that changes and modifications obvious to those skilled in the art may be made.

Claims (1)

[Scope of Claims] 1. A dentifrice composition comprising from about 0.05 to about 7.6% by weight of sodium monofluorophosphate and a compatible abrasive, wherein at least a major portion of the abrasive has a total particle size of less than 3 microns. large, with at least about 65% of all particles having a size of 3
A dentifrice composition that is dicalcium phosphate dihydrate with a particle size that is ~10 microns. 2. The dentifrice composition according to claim 1, wherein dicalcium phosphate dihydrate is the only abrasive introduced.