SE461377B - DISTINCTIVE DENTALS CONTAINING A WATER-SOLUBLE ZINC SALT - Google Patents

Description

Dioxide-containing polishing agents such as silica xerogel have an average particle size between about 2 and 20 microns and generally a surface area of at least about 300 m 2 / g, typically about 300-370 m 2 / g or about 100 microns. soo m 2 / g, as described in U.S. Patent No. 3,538,230, and this avoids an in situ reaction with zinc ion so that a large portion of the theoretically available zinc is lost by physicochemical effects such as absorption.

Similar compatibility problems would occur when water-soluble zinc salt is present together with other dentifrice salt polishes, especially calcium salts such as dicalcium phosphate or calcium carbonate. In fact, it has been assumed that it would be difficult to use water-soluble zinc salt and maintain a high level of zinc ion availability in such conventional dentifrices.

Compatibility is also a problem when alkali metal monofluorophosphate is used in conjunction with silica-containing polishing agent in a dentifrice containing a water-soluble zinc salt.

It has therefore been difficult to prepare dentifrices containing silica-containing polishes and certain amounts of zinc ions with or without alkali metal monofluorophosphate or alkali metal carboxymethylcellulose or both, which remain effective in imparting the astringent properties of zinc and fluoride properties to the anti-vascular properties. In particular, gelling dentifrices which provide both zinc astringent with or without a fluoride which provides anticarious effect have not been available due to the incompatibility of zinc ion with monofluorophosphate and with alkali metal carboxymethylcellulose in the presence of various silica-containing polishes.

The present invention uses a precipitated amorphous silica gel, as described in published British patent application 2,038,303 and in U.S. Patent No. 4, S28, 81.

The said U.S. patent discloses a dentifrice containing the precipitated amorphous silica gel in which a dual source of fluoride containing sodium flupride and sodium monofluorophosphate and a source of calcium are stabilized by an alkali metal phytate to provide improved fluoride retention.

Such precipitated amorphous silica gel material is available from Grace GmbH as a product such as Syloblanc 81, Syloblanc 81C and Syloblanc 82. This product differs from the types of xerogel sold by W. R. Grace and Co. under the trademark Syloid and as specifically described in U.S. Patent No. 3,538,230. Although some products sold by Grace GmbH under the Syloblanc brand were previously or still are available under the Syloid brand, neither Syloblanc 81, Syloblanc 8lC nor Syloblanc 82 have ever been available under the Syloid brand. In particular, it should be noted that the grades of silica gel used in the present invention are less abrasive as the surface area increases, while the grades of silica xerogel described in U.S. Patent No. 3,538,23O are generally more abrasive when their surface area increases.

Due to the low compatibility of most zinc polishes, including the polishes described in U.S. Patent No. 3,538,230, it was completely unexpected that a particular silica-containing polishing material would not present this problem and that further in the presence of this polish the reaction between zinc ions and alkali metal carboxymethylcellulose would be significantly reduced. Furthermore, it was unexpected that in the presence of such particulate silica-containing polishing material and zinc ions, the alkali metal monofluorophosphate remains stable and compatible to release fluoride. Nevertheless, according to the present invention, it has been found that retention of high levels of astringence from zinc ions is achieved when such particulate silica-containing polishing material is used, whether or not alkali metal carboxymethylcellulose is used, or monofluorophosphate is used to give high levels of fluoride. , which are also maintained.

It is an advantage of the present invention that an astringent dentifrice containing zinc ions is provided which may effectively contain monofluorophosphate or an alkali metal carboxymethylcellulose gelling agent or both.

A further advantage of the present invention is that an astringent gelled toothpaste containing zinc ions is provided, which may optionally contain monofluorophosphate or an alkali metal carboxymethylcellulose gelling agent, or both.

Additional advantages of the invention will become apparent from the following detailed description.

In accordance with some of these aspects, the present invention relates to an astringent dentifrice comprising about 20 to 90% by weight of a liquid vehicle comprising water in an amount of at least about 3% by weight of said dentifrice, about 0.05 to 5% by weight of a dentifrice. gelling agent and about 10 to 50% by weight of a polishing agent comprising a synthetic precipitated amorphous silica gel having an average particle size of 1 to 30 microns and a) a surface area of 1 to 600 m 2 / g, b) a pore volume of 0.05 to 0 .5 cm 3 / g, c) a product surface area (in m2 / g) - pore volume (in cm 3 / g) less than or equal to 240, d) a calculated pore diameter of 1.5 - 2.5 nm, and e) a water content of less than 25% by weight; And up to about 5% of a water-soluble zinc salt, which provides at least about 50 ppm of zinc ions to said dentifrices. Furthermore, said dentifrice may contain an alkali metal carboxymethylcellulose as a gelling agent and / or it may contain an alkali metal monofluorophosphate in an amount which gives about 0.01 - 1% fluoride.

As indicated above, the synthetic precipitated silica is of the type described in published British patent application 2,038,303 and U.S. Patent No. 4,528,181. Specific qualities of the silica material described therein are suitable for use in the present invention.

Furthermore, specific grades, which are particularly preferred, are described in a commercial publication from October 1980 published by Grace GmbH of Norderstadt, West Germany, as Syloblanc 81 and Syloblanc 82 which exhibit the following typical physical and chemical properties: SYLOBLANC 81 SYLOBLANC 82 Average particle size - play (according to Coulter) Pm 4 7 Wet sieve residue (42 μm)% 0.02 0.02 pH (5% suspension in water) 3 6 Surface area (BE'r.) '' m3 / g 400 480 Loss on drying% _ 7 4 SiO 2 content (on ignited substance)% 96 99 Refractive index 1.46 1.46 In a variant of Syloblanc 81 which is available as Syloblanc 81C, the pH (5% aqueous suspension) is about 6-8.

Syloblanc 81 and 81lC are particularly highly effective for polishing dental surfaces. Syloblanc 82 has a lower polishing effect, 461 377 10 15 20 25 30 but can be used by consumers who want this reduced effect. Similarly, the qualities of the silica material can be proportioned in mixtures to provide suitable polishing properties. It should be noted that the dentifrices are compatible in unlined aluminum dentifrice tubes, even in the absence of phytate salt, which is necessary according to the invention described in U.S. Patent No. 4,528,181. The precipitated amorphous silica gel is used in an amount of about 10 - 50% by weight, typically about 10 - 40% in a gel-like dentifrice.

Aqueous slurries of the silica materials (e.g., about 5 to 20% slurries) typically have a pH of about 2 to 9. Since the dentifrice composition of the present invention preferably has a pH (measured in a 10% aqueous slurry) of at least about 5.5, for example about 5.5 - 7.5, the pH of the dentifrice can be adjusted with a suitable material such as sodium hydroxide, etc.

The water-soluble zinc salt is present in the dentifrice in an amount of up to about 5% by weight, preferably about 0.01 - 3% and most preferably about 0.1 - 2%. Water-soluble zinc salts in accordance with the present invention are at least about 10% by weight, preferably at least 20%, soluble in water. At least about 50 ppm zinc ions are provided to the dentifrice, preferably at least about 750 ppm and most preferably at least about 1000 ppm zinc ions. Suitable zinc salts include zinc sulfate, zinc chloride, zinc bromide, zinc iodide, zinc nitrate and zinc acetate. In the case of zinc chloride, 0.01% by weight gives about 50 ppm zinc ions and 0.2% by weight gives about 1000 ppm zinc ions, 0.48% by weight zinc sulphate heptahydrate gives about 1000 ppm zinc ions. Furthermore, zinc oxide, a zinc compound with very low solubility (below 0.0005%), can also be added to prevent a lowering of the pH of the product. This acts as a buffer system and improves pH stability and compatibility in unlined aluminum tubes.

It may be present in an amount of about 0.005 - 0.5% by weight.

The dentifrice comprises a liquid vehicle containing about 3 to 60% by weight of water, typically mixed with at least one humectant. The liquid phase comprises about 20 to 90 weight percent of the dentifrice and is generally about 25 to 80 percent liquid, typically about 3 to 50 weight percent, preferably about 3 to 10 weight percent water in a substantially clear gel dentifrice or gel. shaped dentifrice, which would be substantially clear except for the presence of an opacifying agent such as titanium dioxide, and about 11 - 50% water in a misty to opaque gel dentifrice having about 10 to 90 weight percent, preferably about 15 to 80% humectant. Typical homectants include glycerin, sorbitol (for example 70% solution), maltitol, polyethylene glycol having a molecular weight of about 400-600, propylene glycol and mixtures thereof.

The dentifrice also contains a gelling or binder as a solid vehicle, although this may be present in a small amount, as the synthetic precipitated silica may cause a thickening or gelling of the dentifrice to a creamy or pasty consistency.

Alkali metal carboxymethylcellulose is preferred in accordance with one aspect of the invention, but other gelling or binding agents may be present, such as hydroxyethylcellulose, hydroxypropylcellulose, xanthan, carrageenan, iota-carrageenan, gum, polivinylpyrrolidone, starch and mixtures. Such gelling agents may be used in an amount of about 0.05 to 5% by weight, typically about 0.05 - 2% and preferably about 0.1 - 1.5%. The use of sodium carboxymethylcellulose is particularly desirable.

Alkali metal, such as sodium and potassium, monofluorophosphate are compatible with the dentifrice. Sodium monofluorophosphate is especially preferred. In the past, when trying to make a dentifrice with liquid vehicle, gelling agent, polishing agent, zinc salt and sodium monofluorophosphate, significant proportions of zinc ions and fluoride ions have been lost through insolubilization. Completely unexpectedly, when the polish is the defined synthetic precipitated amorphous silica gel, high levels of fluoride ions and significant retention of zinc ions are obtained. Such a high degree of fluoride retention is not achieved when simple fluoride such as sodium fluoride is used.

Sodium monofluorophosphate, Na 2 PO 3 F, in commercially available form, can vary considerably in purity. It can be used in any suitable degree of purity provided that any contaminants do not significantly adversely affect the desired properties. In general, a purity of at least about 80% is desirable and preferably at least 90% by weight should consist of sodium monofluorophosphate with the remainder being primarily impurities or by-products in the preparation, such as sodium fluoride and water-soluble sodium phosphate salt. Expressed in a different manner, the sodium monofluorophosphate used shall have a total fluoride content exceeding 12%, preferably 12.7%, a content of not more than 1,5%, preferably not more than 1.2% free sodium fluoride, and a sodium monofluorophosphate content of at least 12%, preferably at least 12.1%, all calculated as fluoride. Alkali metal monofluorophosphate is present in an amount which gives fluoride in an amount of about 0.01 - 1% by weight, preferably about 0.1%. Thus, sodium monofluorophosphate may be present in an amount of about 0.076 - 7.6%, preferably 0.76%, which corresponds to about 100 - 10000 ppm fluoride, preferably about 1000 ppm. 10 15 20 25 30 461 377 Any suitable surfactant or detergent material may be incorporated into the dentifrice compositions. Such compatible materials are desirable to provide additional detersive foaming and antibacterial properties depending on the specific type of surfactant and are selected accordingly. These detergents are usually water-soluble compounds and may be anionic, nonionic, amphoteric or cationic. The use of water-soluble non-soap or synthetic organic detergents is generally preferred. Suitable detersive materials are known and include, for example, water-soluble salts of higher fatty acid and monoglyceride monosulphate detergent (for example sodium coconut fatty acid monoglyceride monosulphate), higher alkyl sulphate (for example sodium lauryl sulphate), alkylaryl sulphonate (for example, sodium dihydropulphanate; ) and similar.

Additional surfactants include the substantially saturated higher aliphatic acylamides of lower aliphatic aminocarboxylic acid compounds, such as those having 12 to 16 carbon atoms in the acyl radical. The amino acid content is generally derived from the lower aliphatic saturated monoaminocarboxylic acid compounds. Suitable compounds are the fatty acid amides of glycine, sarcosine, alanine, 3-aminopropanoic acid and valine having about 12 to 16 carbon atoms in the acyl group. For optimal effects, the N-lauroyl, myristoyl and palmiund sarcoside compounds are preferably used.

The amino compounds can be used in the form of the free acid or preferably as water-soluble salts thereof, such as the alkali metal, ammonium, amine and alkylolamine salts.

Specific examples thereof are the sodium and potassium N-lauroyl, myristoyl and palmitoyl sarcosides, ammonium and ethanolamine N-lauroyl glycide and alanine; For simplicity, "aminocarboxylic acid compound", "sarcoside", and the like herein refer to compounds having a free carboxylic acid group or the water-soluble carboxylate salts.

Such materials are used in pure or substantially pure form.

They should be as free as practicable or similar to higher fatty acid materials which tend to reduce the activity of these compounds. Normally the amount of this higher fatty acid material is less than 15% by weight of the amide and in an amount insufficient to adversely affect it, and preferably less than about 10% of said amide material.

Other particularly suitable surfactants include nonionic agents such as condensate of sorbitan monostearate with about 20 moles of ethylene oxide, condensate of ethylene oxide with propylene oxide, condensate of propylene glycol ("Pluronic material") and amphoteric agents such as long chain (alkyl-) amide-alkylene- alkalized amine derivatives available under the trademark "Miranol" CZM Cationic surfactant germicides and antibacterial compounds such as diisobutylphenoxyethoxyethyldimethylbenzylammonium chloride, benzyldimethylstearylammonium chloride, tertiary amines having a fatty alkyl carbon group (having 12 - alkylene group) bound to the nitrogen) typically containing a total of about 2 to 50 ethanoxy groups per molecule) and salts thereof with acids, and compounds having the structure (CH 2 CH 2 O) x H (CH 2 CH 2 O) x H RN cnzc fi zcnzzy (CH2CH 2 O) yH where R is a fatty alkyl group containing about 12 - 18 carbon atoms, and x, y and z in total are 3 or a higher number, as well as salts thereof with mineral or organic s dizziness, can also be used. Preferably, about 0.05 to 5% by weight of the above surfactant material is used in the oral preparation according to the present invention.

Various other materials may be incorporated into the dental creams of the present invention. Examples are opacifiers, preservatives, stabilizers, silicones, chlorophyll compounds and ammonia-treated materials such as urea, diammonium phosphate and mixtures thereof. These additives are incorporated into the present compositions in amounts which do not substantially adversely affect the desired properties and characteristics and are suitably selected and used in conventional amounts.

For certain purposes, it may be desirable to incorporate antibacterial agents into the compositions of the present invention. Typical antibacterial agents which may be used in an amount of about 0.01 to 5% by weight, preferably about 0.05 to 1.0% by weight of the dentifrice composition include cetylpyridinium chloride, benzethonium chloride as well as: N1-4 (chlorobenzyl) - N5 p-chlorophenyl biguanide; - (2,4-dichlorobenzyl) biguanide; 4-chlorobenzylhydryl biguanide; 4-chlorobenzylhydrylguanylurea; N-3-lauroxypropyl-N5-p-chlorobenzyl biguanide; 1,6-di-p-chlorophenylbiguanidohexane; 1- (lauryl dimethylammonium) -8- (p-chlorobenzyldimethylammonium) -5,6-dichloro-2-guanidinobenzimidazole; N1-p-chlorophenyl-N5-lauryl biguanide; 5-amino-1,3-bis (2-ethylhexyl) -5-methylhexahydropyrimidine; and their non-toxic addition salts. Suitable flavoring or sweetening materials may be utilized in providing an aroma to the compositions of the present invention. Examples of suitable flavoring ingredients include the aromatic oils, for example oils of green mint, peppermint, evergreens, sassafras, cloves, sage, eucalyptus, marjoram, cinnamon, lemon and orange, as well as methyl salicylate. Suitable sweeteners include sucrose, lactose, maltose, sorbitol, sodium cyclamate, sodium saccharin, dipeptides of U.S. Patent No. 3,939,261 and oxathiazine salts of U.S. Patent No. 3,932,606.

Suitable flavors and sweeteners may together constitute about 0.01-5% or more of the composition.

The dentifrice is packaged in a container from which it can be easily extruded, such as a pressure differential or mechanically actuated dental cream dispenser or a lined or unlined aluminum tube or wax lined lead tube or plastic tube, which may be laminated with aluminum. The rheological properties are very suitable for a mechanically actuated discharge container of the type described in British Patent Application 2,070,695, published September 9, 1981. This discharge container comprises a discharge nozzle, a clamping part, a central rod, a piston and a hand control device. .

Pressure differential dispensing containers can be of the aerosol or vacuum type. Suitable pressure differential discharge containers are those having a collapsible product-containing bag arranged in a rigid container containing a propellant. In such dispensing containers, operation of the valve allows discharge of the product only, since the propellant is separated from the product by the fluid impermeable bag. Dispensers of this type are described in U.S. Patent Nos. 3,828,977 and 3,838,796. These are so-called Sepro dispensers. Exxel and Envirospray containers also use pressure. Still other types of dispensers are the barrier piston container described in US 4,171,757. This container comprises a valve, a product-containing chamber and a substantially fluid-tight barrier piston, which separates the propellant from the enclosed product (the so-called Diamond container).

The dentifrice is prepared by forming a premix of the gelling agent with the liquid vehicle components, for example water and humectant, which may also contain additional ingredients such as the monofluorophosphate and / or sweetener, and mixing the synthetic precipitated silica gel therewith and zinc zinc dioxide gel. Additional ingredients may then be added. Although the invention is described in connection with illustrative examples, it will be apparent to those skilled in the art that various modifications may be made therein which fall within the scope of the invention. All amounts are by weight unless otherwise indicated.

EXAMPLE 1 The following unpainted gelling dentifrices are prepared and placed in unlined aluminum tubes: DELAR AB Glycerin 25,000 25,000 Sorbitol (70%) 47,050 43,830 Xanthan 0.260 0.260 Sodium saccharin 0.170 0.170 Titanium dioxide 1,000 1,000 Water 3,000 3,000 Zinc sulphate phosphate amphiate 80 20 25 461 377 14 cont.

Silica xerogel ** - 17,000 1 Silica aeorgel *** - 6,500 Sodium hydroxide (40%) 0.280 - Sodium lauryl sulphate 1,760 1,760 Flavor 1,000 1,000 pH (20% slurry) 5,9 '6,1 * Syloblanc 81 from Grace GmbH; ** Syloid AL1 from Grace GmbH, formerly known as Syloid 63; *** Syloid 244, thickener from W.R. Grace and Co.

The theoretical amount of soluble zinc ions in each of the gel dentifrices is 1000 ppm or 0.100%.

The dental care agent A does not require the presence of thickening material to give the desired gel character. Its consistency roughly corresponds to the consistency of a dentifrice B.

Each of the dentifrices is aged at room temperature and at 43 ° C. Both maintain largely equivalent desirable consistencies. The bridge percentages of soluble zinc ions available in each of the dentifrices are determined to be as follows:% Zn2 + -Room temperature 43 ° C 1 3 2 1 3 Initial Month Months Weeks Months Months Dentures A 0,084 0,080 0,05 0,091 0,070 0,050 Dentists B 0,0549 0,048 0,00 0,00.

Dental care product A containing Syloblanc 81 maintains superior levels of soluble zinc ions compared to the otherwise substantially equivalent dental care product B containing Syloblanc AL1.

Similar superior retention levels of soluble zinc ions are achieved when Syloblanc 81 in dentifrice A is replaced with Syloblanc 82 and the following mixture of Syloblanc 81 and 82, with the proportions of sodium hydroxide reduced or omitted, with corresponding amounts of sorbitol (70%) added.

Similarly, superior retention levels of soluble zinc ions are achieved when Syloblanc 81 is replaced with Syloblanc 81C, with sodium hydroxide omitted and the corresponding amount of sorbitol added (70%). 0.25 parts of zinc oxide are incorporated into each of the dentifrices A and B instead of the corresponding amounts of sorbitol, thereby stabilizing the pH during aging and improving the compatibility with unlined aluminum tubes for longer periods.

EXAMPLE 2 The following unpainted gelling dentifrices are prepared and placed in unlined aluminum tubes: DELAR AB Glycerin 25,000 25,000 Sørbitøl (70%) 47,050 43,550 Sodium carboxymethylcellulose 0,260 0,260 Sodium saccharin 0,170 0,170 Titanium dioxide 1,000 1,000 Ammonium gelophthalate ** - 17,000 10 15 20 25 461 377 16 cont.

Silica airgel *** - 6,500 'Sodium hydroxide (40%) 0,280 0,280 Sodium lauryl sulphate 1,760 1,760 Flavor 1,000 1,000 pH (20% slurry) 5,9 6,1 * ** *** 7 7 - See example l.

The theoretical amount of soluble zinc ions in each dentifrice is 1000 ppm or 0.100%.

The dental care product does not require the presence of thickening material to initially give the desired gel character.

Each dentifrice ages at room temperature and at 43 ° C. Both maintain essentially the corresponding desired consistencies. The percentages of soluble zinc ions available in each dentifrice are determined to be as follows:% Zn2 + -Room temperature 43 ° C - l 3 2 1 3 Initial Month Months Weeks Months Months Denture A 0,080 0,079 0,050 0,082 0,069 0,050 Denture B 0,02 A 0,02 0,00 81 retains gel character and superior levels of soluble zinc ions compared to the otherwise substantially equivalent dentifrice B containing Syloblanc 63. When conventional 7 MXF grade sodium carboxymethylcellulose is used, phase separation and degradation occur in the presence of Syloid 63 polishing agent. 17, which does not occur to the same extent when Syloblanc 81 is used.

It should be noted that the levels after two weeks and one month for dentifrice B at 4306 reflect routine experimental variations.

Similar superior retention levels for soluble zinc ions are achieved when Syloblanc 81 in dentifrice A is replaced with Syloblanc 82 and with a 1: 1 mixture of Syloblanc 81 and 82, each with reduced sodium hydroxide levels or omitted sodium hydroxide, with corresponding amounts of sorbitol ( 70%).

Similarly, superior retention levels of soluble zinc ions are achieved when Syloblanc 81 is replaced with Syloblanc 81C, with sodium hydroxide omitted and the corresponding amount added to Sorbitol (70%). 0.25 parts of zinc oxide are incorporated into each dentifrice A and B instead of the corresponding amounts of sorbitol, thereby stabilizing the pH during aging and improving the compatibility with unlined aluminum tubes for extended periods.

EXAMPLE 3 The following unpainted gelling dentifrices are prepared and placed in unlined aluminum tubes: 10 15 20 25 18 PARTS IAB Glycerin 25,000 25,000 Sorbitol (70%) 46,340 46,880 Sodium carboxymethylcellulose 0,190 0,190 Sodium saccharin 0,170 0,1ate 0,2ate 0.220 Precipitated amorphous silica gel * 20,000 20,000 Sodium hydroxide (40%) 0.300 0.300 Sodium lauryl sulphate 1,760 1,760 Flavor 1,000 1,000 pH (20% slurry) 6.0 5.9 * - See Example 1.

The theoretical amounts of soluble zinc ions and fluoride in each of the gelling dentifrices are 1000 ppm or 0.100%, for both zinc ions and fluoride.

Both dentifrices age at room temperature and at 43 ° C. The percentages of soluble zinc ions and fluoride available in each dentifrice are determined to be as follows at room temperature:% Zn 2+; % Monofluorophosphate as fluoride (Denture A); % Fluoride (Denture B) Room temperature Initial 1 month Dent A A 0.66 Zn 0.066 Zn 0.096 F 0.097 F r; 10 15 20 25 l9 cont. 0.070 Zn 0.100 F 0.051 Zn 0.048 F Dental care product B Dental care product A containing sodium monofluorophosphate provides significant retention of both zinc ions and fluoride compared to dental care product B containing sodium fluoride. At 43 ° C, gas is formed in the unlined aluminum tube containing dentifrice B, while the unlined aluminum tube containing dentifrice A remains stable.

Zinc ion and fluoride retention is low when xerogel Syloid 63, from W. R. Grace & Co., replaces Syloblanc 81.

Similar results as those obtained with dentifrice A are obtained when potassium monofluorophosphate replaces sodium monofluorophosphate.

Similar superior retention levels for soluble zinc ions and fluoride are achieved when Syloblanc 81 in dentifrice A is replaced with Syloblanc 82 and with a 1: 1 mixture of Syloblanc 81 and 82, each with the proportions of sodium hydroxide reduced or omitted by corresponding amounts. added to sorbitol (70%) L Similarly, superior retention levels for soluble zinc ions and fluoride are achieved when Syloblanc 81 is replaced with Syloblanc 81C, with sodium hydroxide released and its amount added to sorbitol (70%). 0.25 parts of zinc oxide are incorporated into each of the dentifrices A and B instead of the corresponding amounts of sorbitol, thereby stabilizing the pH during aging and improving the compatibility with unlined aluminum tubes for extended periods. EXAMPLE 4 The following stable visually clear gelling dentifrices are prepared and placed in unlined aluminum tubes: PARTS ABCD Glycerin 25,000 25,000 25,000 25,000 Sorbitol (70%) 48,310 48,590 48,590 48,450 Xanthan 0.260 0.260 0.270 0.270 0.2in 0.260 0.2 3,000 3,000 3,000 Zinc chloride 0.020 0.020 0.020 0.020 Syloblanc 81 20,000 - - 10,000 Syloblanc 8lC - 20,000 - - Syloblanc 82 _ - 20,000 10,000 Sodium hydroxide (40%) 0.280 - - 0.140 Sodium lauryl sulphate 1,760 1,760 1,760 1,760 Flavor 1,000 1,000 1,000 1,000 1,000 0.200 0.200 0.200 0.200 EXAMPLE 5 The following stable visually clear gelling dentifrices are prepared and placed in unlined aluminum tubes: PARTS ABCD Glycerin 25,000 25,000 25,000 25,000 Sorbitol (70%) 48.310 48.590 48.590, 48.450 Sodium carboxymethylcellulose 3,00070 0.12 0.260 0.260 0.260 0.260 0.260 0.260 0.260 0.260 0.260 0.260 0.260 0.260 3,000 Zinc chloride 0.020 0.020 .0.020 0.020 10 15 20 25 30 cont.

Syloblanc 81 Syloblanc 8lC Syloblanc 82 Sodium hydroxy (40%) Sodium lauryl sulphate Flavor Blue dye solution 11%) 461 577 21 PARTS AB c 0 20,000 _ - 10,000 - 20,000 - - - - 20,000 10,000 0,200 - - 0,140 1,760 1,760 1,760 1,760 1,760 1,000 1,000 1,000 0.200 0.200 Similar stability is obtained when potassium carboxymethylcellulose replaces natriumkarboximetylcellulosa_ EXAMPLE 6 the following stable visually clear gel dentifrice is prepared and placed in unlined aluminum tubes: Glycerin Sorbitol (70%) Xanthan Sodium Water Sodium monofluorophosphate Zinc chloride Syloblanc 81 Syloblanc 81C Syloblanc 82 Sodium hydroxide (40%) Sodium lauryl Flavor Blàfärgslösning ( l%) DELAR AB c 0 25,000 25,000 25,000 25,000 47,550 47,630 47.030 47.690 0.260 0.260 0.260 0.260 0.260 0.170 0.170 0.170 0.170 3,000 3,000 3,000 3,000 3,000 0.760 0.760 0.760 0.760 0.020 0.020 0.020 0.020 20,000 - - 10,000 - 20,000 - - - - 20,000 10,000 0.200 - _ 0.140 1.760 1.760 1.760 1.760 1,000 1,000 1,000 1,000 0.200 0.2 00 0,200 0,200 10 15 20 25 461 377 22 EXAMPLE 7 The following misty and opaque gel dentifrices are prepared and packaged in mechanically actuated dispensing containers: PARTS ABCD Glycerin 25,000 25,000 25,000 25,000 Sorbitol (70%) 24,970 24,870 24,870 24,870 Iotone carrageenan 0,700 0,170 0,170 0,170 0,170 Water 25,000 25,000 25,000 25,000 Zinc bromide dihydrate 0,400 - - - Zinc iodide - 0,500 - - Zinc nitrate hexahydrate - - 0,500 - Zinc acetate dihydrate - - - 0,500 Syloblanc 81C 21,000 21,000 21,000 21,000 Sodium laurylsulfate 1,1000 sodium 1,160 sodium saccharin.

EXAMPLE 8 The following stable misty and opaque gelling dentifrices are prepared and placed in unlined aluminum tubes: PARTS ABCD Glycerin 25,000 25,000 25,000 25,000 Sorbitol (70%) 24,970 24,870 24,870 24,870 Sodium carboxymethylcellulose 46 46,770 0,70 25,000 0,70 0,70 0,70 0,70 577 23 cont.

PARTS A B C D Zinc Bromide Dihydrate 0,400 - ~ - Zinc Iodide - 0,500 - - Zinc Nitrate Hexahydrate - - 0,500 - Zinc Acetate Dihydrate - - - 0,500 Syloblanc 8lC 21,000 21,000 21,000 21,000 Sodium Lauryl Sulfate 1,760 1,760 1,760 1,760 1,160 Nuclear sodium 1,000

EXAMPLE 9 The following stable misty and opaque gelling dentifrices are prepared and packaged in mechanically actuated dispensing containers: Glycerin Sorbitol (70%) Iota-carrageenan Sodium saccharin Water Sodium monofluorophosphate Zinc bromide dihydrate dihydrate Zinc bromide dihydrate Zinc citrate 25,000 25,000 25,000 24,210 24,110 24,110 24,110 0,700 0,700 0,700 0,700 0,170 0,170 0,170 0,170 25,000 25,000 25,000 25,000 25,000 0,760 0,760 0,760 0,760 0,400 - - - - 0,500 - - - - 0,500 - - - - 0,500 21,000 21,000 21,000 21,000 1,760 1,760 1,160 1,760 1,7 1,000 461 577 24 In the examples, sodium cyclamate may replace sodium saccharin.

It will be apparent to those skilled in the art that further modifications of the examples illustrating the invention may be made.

.FI R /

Claims (16)

10 15 20 25 461 377 25 P a t e n t k r a v Astringent dentifrice, characterized in that it comprises about 20 to 90% by weight of liquid vehicle comprising water in an amount of at least about 3% by weight of said dentifrice, about 0.5 to 5% by weight of a gelling agent and about 10% by weight. - 50% by weight of a polishing agent, comprising a synthetic precipitated amorphous silica gel with an average particle size of 1 - 30 Pm and a) a surface area of 1 - 600 m2 / g, b) a pore volume of 0.05 - 0.5 cm 3 / g, c) a product surface area (in m2 / g) X pore volume (in cm3 / g) less than or equal to 240, d) a calculated pore diameter of 1,5 - 2,5 nm and e) a water content of less than 25% by weight , and with up to about 5% of a water-soluble zinc salt, which provides at least about 50 ppm of zinc ions to said dentifrice. An astringent dentifrice according to claim 1, characterized in that the gelling agent is an alkali metal carboxymethylcellulose gelling agent. An astringent dentifrice according to claim 1 or 2, characterized in that it additionally contains an alkali metal monofluorophosphate in an amount of about 0.01 - 1% fluoride ions. Astringent dentifrice according to any one of claims 1, 2 or 3, is present in an amount of 0.01 - 3% by weight. k ä n n e t e c k n a t of the zinc salt 461 10 15 20 25 26 An astringent dentifrice according to any one of claims 1, 2 or 3, characterized in that said zinc salt is selected from the group consisting of zinc sulphate, zinc chloride, zinc bromide, zinc iodide, zinc nitrate and zinc acetate. An astringent dentifrice according to claim 5, characterized in that the zinc salt is zinc sulphate heptahydrate. An astringent dentifrice according to claim 5, characterized in that the zinc salt is zinc chloride. An astringent dentifrice according to claim 1, characterized in that the water in said liquid vehicle constitutes about 3 to 10% by weight of said dentifrice and that said synthetic amorphous silica gel constitutes about 10 to 40% by weight of said dentifrice. The astringent dentifrice of claim 1, characterized in that the water in said liquid vehicle constitutes about 11 to 50% by weight of said dentifrice. Astringent dentifrice according to claim 1, characterized in that said synthetic amorphous silica gel is at least one of the synthetic amorphous silica gels having the following characteristics: abc Average particle size (according to Coulter) Pm 4 7 4 Moisture residue (42 Fm)% 0.02 0.02 0.02 pH (5% suspension in water) 3 6 6 - 8 Surface area (BET) m2 / g 7 4 7. v, maa .., .til 10 15 20 25 461 577 27 cont. a b c Drying loss% 7 4 7 Silica content (on ignited substance) 96 99 96 Refractive index 1.46 1.46 1.46 11. ll. Astringent gelling dentifrice according to any one of claims 2, 4 or 5, characterized in that said gelling agent is sodium carboxymethylcellulose. An astringent dentifrice according to any one of claims 3, 4 or 5, limetone monofluorophosphate is sodium monofluorophosphate. k ä n n e t e c k n a t by the fact that said The astringent dentifrice of claim 4, characterized in that said water-soluble zinc salt is present in an amount that provides about 1000 ppm of zinc ions and that said alkali metal monofluorophosphate is present in an amount that provides about 1000 ppm of fluoride. An astringent dentifrice according to claim 13, characterized in that said zinc salt is zinc sulfate heptahydrate and that said alkali metal monofluorophosphate is sodium monofluorophosphate. An astringent dentifrice according to any one of claims 1, 2 or 3, the dentifrice is packaged in an unlined aluminum tube. k ä n n e t e c k n a t of that said Astringent dentifrice according to any one of claims 1, 2 or 3, dentifrice also contains about 0.005 - 0.5% by weight of said dentin zinc oxide.