SE453459B - TANDKREM - Google Patents

Description

453 459 which contains a non-active type surfactant and a special binder, and which gives a desired stable and full-bodied foam.

Another advantage of the invention is that the toothpaste produced is sweet without the need for the addition of sweetener, and not irritating, while at the same time it does not tend to cause the consumer to get ulceration in the oral mucosa or an unpleasant citrus taste after the use of the toothpaste.

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

Thus, the present invention relates to a toothpaste containing 20 to 80% by weight of liquid humectant, 0.5 to 7% by weight of xanthan gum and 1 to 10% by weight of a nonionic polyoxyethylene-polyoxypropylene block polymer as the sole surfactant. Preferably it also contains up to 5% by weight of resinous poly (ethylene oxide).

The nonionic type surfactant used in the invention is a block polymer containing the polyoxyethylene and polyoxypropylene. These block polymers may be incorporated by W andotte Chemicals Corporation under the trademark Pluronias. They may be liquid, pasty or solid and are generally defined chemically by the molecular weight of the hydrophobic polyoxypropylene moiety and the weight percent of the hydrophilic polyoxyethylene moiety. The following block polymers can be obtained from Wyandotte: Pluron- Physical number properties L 121 Liquid L 101 "L 81" L 61 "L 31" L 122 Liquid L 92 "L 72" L 52 "L 42" P 123 Paste P 103 " L 63 Liquid L 43 "P 104 Paste P 94" P 84 "L 64 Liquid L 44" P 105 Pasta P 85 "P 75" P 65 "L 35 Liquid F 127 Solid F 87" 77 Hydrophilic 10 10 10 10 10 20 20 20 20 20 30 30 30 30 40 40 40 40 40 40 50 50 50 50 50 70 70 70 453 459 Molecular weight hydrophobic 4000 3250 2250 1750 950 4000 2750 2050 1750 1200 4000 3250 1750 1200 3250 2750 2250 1750 1200 3250 2250 2050 1750 950 4000 2250 2050 Pluron- Physical Hydrophilic Molecular Weight Properties Hydrophobic F ÉD8 Solid 80 3250 F 98 "80 2750 F 88" 80 2250 F 68 "80 1750 F 38" 80 950 The preferred nonionic block polymers are solid (or flaky) materials and the most preferred is Pluronic 108 (80% polyoxyethylene: polyoxypropylene molecular weight equal to 3250) and F 87 (70% polyoxyethylene: polyoxypropylene molecular weight equal to 2250); a surfactant is used in the toothpaste in an amount of about 1 - 10% by weight, preferably about 2 - 5% by weight and in particular about 3% by weight.

The system of binder or gelling agents of xanthan or xanthan and resinous poly (ethylene oxide) cooperates with the non-ionic substance to give a stable full-bodied foam (although the one surfactant present is of non-ionic type) and a toothpaste which gives the desired mouthfeel. Xanthan gum, in the mentioned concentrations allows the formation of a stable full-bodied foam. Furthermore, in accordance with another object of the invention, the mouthfeel may be modified, as mentioned, by the addition of resinous poly (ethylene oxide). The toothpaste has a suitable viscosity to be able to squeeze out the toothpaste tube in the form of a string.

Resinous poly (ethylene oxide) has been described as a gelling or binder in toothpaste in U.S. Pat. No. 2,991,229 to Ivison. The presence of it makes the consistency of the toothpaste more even. The poly (ethylene oxides) used in the invention are solid, colorless, water-soluble resins. They appear to form homogeneous systems with water in all proportions, although the relatively high molecular weight ethylene oxide polymers only swell upon the addition of small quantities of water. When larger quantities of water are added, the polymers dissolve.

The aqueous solutions are viscous, the viscosity increasing with both the concentration of the polymer in the solution and the reduced viscosity of the polymer. The ethylene oxide polymers used in the present invention show very little change with respect to the melting point with increased reduced viscosity (an indication of increased molecular weight) and the melting point, indicated as with temperature changed stiffness, has been found to be about 65 ° C in 2 ° C by the whole range for reduced viscosities between about 1.0 and about 10, and higher. On X-ray examination, the polymers show a crystalline structure similar to that of polyethylene. The crystallization temperature, determined by measuring the fracture in the cooling curve, is about 55 ° C. To make it easier to understand the present invention, various terms are to be defined. It should first be mentioned that the term "poly (ethylene oxide)" as used in the specification and claims refers to ethylene oxide polymers, having a reduced viscosity in acetonitrile of at least 0.5 and up to 75, and higher.

Unless otherwise indicated, the term "reduced viscosity" as used herein means a value obtained by dividing the specific viscosity by the concentration of ethylene oxide polymer in the solution, the concentration being measured in grams of polymer per 100 ml of solvent at a given temperature, and is considered as a measurement of the molecular weight.

The specific viscosity is obtained by dividing the viscosity of the solution and the viscosity of the solvent by the viscosity of the solvent. The reduced viscosities given here are measured at a concentration of 0,2 grams of poly (ethylene oxide) in 100 ml of acetonitrile at 30 ° C (unless otherwise stated). indicated).

Granulated poly (ethylene oxide) is prepared by suspension polymerization of a stirred reaction mixture containing ethylene oxide in contact with a polymerization catalyst therefor and in the presence of an inert organic diluent, e.g. heptane, in which the ethylene oxide is soluble and the resulting poly (ethylene oxide) ) is insoluble. Granulated poly (ethylene oxide) thus prepared is obtained in the form of finely divided solid particles and resembles finely divided sand in particle size. Unlike the granulated poly (ethylene oxide) obtained in the suspension polymerization process, the block and solution polymerization processes give a polymer which is essentially a homogeneous mass either adapted to the shape of the reaction vessel, or, after evaporation of the organic medium, for example by for example with a Marshall Mill (in vacuum hot pressing, and at a slightly elevated temperature), in the form of discs or sheets. This polymer can then be decomposed into smaller particle sizes, for example into groats or the like.

The term "granulated" refers to the particle size of the ethylene oxide polymers prepared by suspension polymerization. A granulated product is a product that is in free-flowing form and contains particles with an average size of less than 5 mesh (sieve size according to American standards). When included, the poly (ethylene oxide) constitutes up to 5% by weight of the toothpaste, preferably about 0.1 - 1.5% by weight.

Xanthan gum is a fermentation product produced by the action of the bacterial type Xanthomonas on carbohydrates. Four 453 459 species of Xanthomonas, namely §¿ campetris, §¿ phaseoli, §¿ malvocearum and §¿ carotae, are described in the literature as the most effective rubber producers. Although the exact chemical structure has not been determined, it is generally accepted that it is a heteropolysaccharide with a molecular weight of several millions. It contains D-glucose, D-mannose and D-glucuronic acid in a molar ratio of 2.8: 3: 2.0. The molecule contains 4.7% acetyl and about 3% pyruvate. The proposed chemical structure can be seen in McNeely and Kang, Industrial Gums, ed. R.L. Whistler, CH XXI, 2nd Edition, New York, 1973. The procedure for the fermentation, isolation and purification of the xanthan gum is described in Manufacturing Chemist, May 1960, pages 206-208 (mentioning on page 208 a possible use of the rubbers described therein). in the manufacture of toothpaste).

The use of special grades of xanthan gum, as described in U.S. Patent No. 4,263,399, is within the scope of the present invention. One grade described in U.S. Patent 4,263,399 is a xanthan gum in which up to about 1.6% of the carboxyl groups are attached to calcium and the remaining carboxyl groups are attached to sodium, potassium, a mixture of sodium and potassium. or other non-calcium cations.

The xanthan gelling agent is present in an amount of about 0.5 - 7% by weight of the toothpaste, preferably about 1.5 - 3% by weight.

Since the surfactant used according to the present invention is of the nonionic type, the weak bitter taste which the anionic substances contribute can not be perceived by the consumers. Consequently, the sweeteners which are often added to toothpastes, at least in part in order to overcome the bitter taste, are less necessary in the toothpaste according to the invention, compared with what has previously been customary. Completely satisfactory sweetening can in fact be easily achieved with the help of the slightly sweetening properties of many of the humectants which are usually included in toothpaste compositions. The moisturizers are incorporated into the liquid phase of the toothpaste, typically together with the water. Typical humectants are sorbitol (as a 70% solution), glycerin, maltitol, xylitol, polyethylene glycol 400 and polyethylene glycol 600. The liquid phase constitutes about 20-80% by weight of the toothpaste, preferably about 30-60%. % by weight, whereby the water (if any) is typically included in an amount of up to about 60% by weight and the humectant typically constitutes about 20-60% by weight. It has been found that maltitol is listed as an ingredient in toothpaste in Japanese Patents 73/10241 and 65/15120.

The liquid vehicle and gelling agent as well as the other components of the toothpaste are balanced so as to obtain a cream or gelled mass with the desired consistency, which can be squeezed out of an aerosol or pump package or from a compressible tube (of eg aluminum, lead or plastic).

The toothpaste generally contains a dentally acceptable polish, which is generally substantially insoluble in water and of the type commonly used in toothpastes. Typical polishes are, for example, dicalcium phosphate, tricalcium phosphate, insoluble sodium metaphosphate, aluminum hydroxide including hydrated alumina, calcined alumina, colloidal silica, magnesium carbonate, calcium carbonate, calcium pyrophosphate, bentonite, etc., and also suitable mixtures. When included, the water-insoluble phosphate salts are preferably used as polishes, and in particular insoluble sodium metaphosphate and / or calcium phosphate, such as dicalcium phosphate dihydrate, in the toothpastes. When visibly clear gels or opaque gels are used, a polloid of colloidal silica, such as those sold under the trademark Syloid as Syloid 72 and Syloid 74, or under the trademark Santocel as Santocel 100, as well as synthetic alkali metal aluminosilicate complexes or silica complexes in combination with alumina, be especially suitable.

When polishes are used, the content thereof is generally between about 15 and 75% by weight in a toothpaste and between about 5 and 50% by weight in a clear or opaque gel.

A further object of the present invention is to provide a toothpaste which contains a silica-containing polish, such as those mentioned in the preceding paragraph, and poly (ethylene oxide) as previously described.

Based on prior art, as described in U.S. Patent 3,020,230 to Smith, which states that silica material coagulates or flocculates in the presence of resinous poly (ethylene oxide) and precipitates from a liquid suspension, one skilled in the art of toothpaste manufacturing would can not be persuaded to use silica material in a toothpaste containing resinous poly (ethylene oxide). In fact, according to U.S. Pat. No. 2,991,229 to Ivison, the polishes or abrasives contained in a toothpaste containing poly (ethylene oxide) are "tricalcium phosphate, dicalcium phosphate and calcium carbonate and the like"; but not silica-containing materials.

It is an advantage: this embodiment of the present invention to provide a toothpaste with improved stain removal properties, which has an acceptable cosmetic rheology and dentin abrasive properties. Another advantage is that a desired foaming is obtained by the inclusion of polyoxyethylene-polyoxypropylene block polymer and xanthan in the toothpaste.

Additional benefits will be apparent from the following description.

As mentioned above, and especially in the case of a clear or opaque gel, the content of the silica-containing polish is in the range between 5 and 50% by weight of the toothpaste, preferably between 10 and 30% such as between 10 and 25%. %. This polish is an alkali metal aluminum silicate complex with a refractive index of between 1.44 and 1.47, and it contains at least 70% silica, up to 10% alumina, such as about 0.1 - 10%, eg about 0.1 - 3% preferably up to about 20% moisture, such as about 0.5 - 10%; and up to about 10% alkali metal oxide. Typically, this material has a particle size in the range of up to about 40 microns, preferably 1 to 4 microns. The preferred moisture content is between 5 and 20%, measured by heating to 1000 ° C, and the typical alkali metal oxide content is between 5 and 10%. In general, the polishing agent has a loose bulk volume of up to 0.2 g / cm 3, such as between 0.07 and 0.12 g / cm 3. Another suitable type of polish is porous amorphous silica having an average particle size which is preferably less than 20 microns and greater than 11 microns, a surface size of at least 200 m 2 / g, preferably at least 300 m 2 / g, and a bulk volume of at least 0.15 g / cm 3, preferably at least 0.30 g / cm 3, such as a dehydrated silica-Hydrogen (ie a xerogel), preferably of the well-known normal density type or intermediate type.

Examples of amorphous silica type polishes are Syloid 63, Syloid 72 and Syloid 74 (Syloid is a trademark), which are described in "The Davison Family of Syloid Silicas" published by the manufacturer, Grace, Davison Chemical Company. Santocel 100 from Monsanto (Santocel is a trademark) is also a suitable dental abrasive.

Syloid 72 has an average particle size of about 4 microns, a surface size of about 340 m 2 / g and a bulk volume of about 1.77 g / cm 3. For Syloid 63, the corresponding figures are about 9 microns, about 675 m2 / g and about 0.4 g / cm3. A quality of Santocel 100 has a surface size of about 239 m2 / g and a bulk volume of about 0.24 g / cm3. These amorphous silica hydrides can be used alone or in mixtures.

As mentioned above, the poly (ethylene oxide) constitutes about 0.05 - 5% by weight of the toothpaste, preferably about 0.1 - 1.5%.

In the toothpaste, the silica-containing polish flocks in âitu in the presence of poly (ethylene oxide). The flocculated particles can typically agglomerate with each other and have visible particle sizes of up to about 250 microns or more, typically about 44 - 177 microns; in other words, the flocculated particles can typically pass through a sieve according to the American sieve standard No. 80 and be retained on a sieve according to the American sieve standard no. 325.

Despite the presence of the flocculated particles, the toothpaste can be easily processed to a desired appearance and a rheological consistency without getting an inappropriate "lumpy" appearance or any "grainy" feeling. The liquid vehicle in the toothpaste according to the invention may be any of the above, and the components in the toothpaste are adapted so as to obtain a cream or gelled mass of desired consistency which can be squeezed out of an aerosol or pump container or a compressible tube (t). of aluminum, lead or plastic).

The total quantity of gelling agent or binder in the toothpaste can be about 0.1 - 12% by weight.

In one embodiment of the toothpaste of the invention, the humectant present is maltitol and the polish is an alkali metal aluminum silicate complex. This toothpaste is transparent.

In recent years, transparent toothpastes have emerged, which contain a dental cleaning or polishing agent. These cleaning or polishing agents have generally been of the silicon-like type and with a refractive index of about 1.44 - 1.47.

The use of these materials has made it possible to produce toothpastes in which the refractive index of the liquid vehicle corresponds to the same of the silicon-like polish. This has typically been accomplished by using glycerol and / or sorbitol as a humectant in the liquid vehicle, since glycerol has a refractive index of 1.473 and sorbitol has a refractive index of 1.460 (70% aqueous solution). However, as water has a refractive index of 1,333, only very little water (ie, in addition to that associated with other components such as sorbitol) has been able to be added without significantly reducing the refractive index and causing a reduced or forged transparency.

Attempts have been made to produce visually clear toothpastes in which smaller amounts of glycerol and / or sorbitol could be tolerated. For example: (1) In U.S. Patent 3,842,167 to Block et al., Maltodextrin 13 is added as a non-moisturizing component in the liquid phase to reduce the amount of glycerol and / or sorbitol required; (2) In U.S. Patent No. 3,927,202 to Harvey et al., Various non-silicon phosphate polishes are used which allow a modification of the refractive index range of the liquid vehicle; In U.S. Pat. No. 4,007,260 to Kim, a silicon-like polish having a refractive index of about 1,410-1,440 was used.

It is an advantage in this embodiment of the present invention to provide a visually clear toothpaste in which a liquid vehicle is present which includes a humectant having a refractive index of about 1.48 (eg about 1.4750 to about 1.4849) and water.

It is a further advantage that an increased quantity of free water can be added, compared to what was previously used in visually clear toothpastes containing an alkali metal aluminum silicate polish with a refractive index of about 1.44 to about 1.47 and a humectant. with a refractive index of about 1.48. The quantity of water is not so high that it causes an undesired drying of the toothpaste due to marked evaporation of water, especially in view of the presence of maltitol. Other advantages will be apparent from the following detailed description.

Thus, the present invention also relates to a visually clear toothpaste containing a vehicle consisting of about 0.5 - 10% by weight of a solid part consisting of gelling agent and about 50 - 94.5% by weight of a liquid part consisting of (a) a humectants in which maltitol having a refractive index of about 1.48 is present as the sole or major non-aqueous component of the liquid vehicle and (b) water in a quantity which gives the liquid vehicle a refractive index of between about 1, 44 and about 1.47, the visually clear toothpaste also containing about 5 - 50% by weight of an alkali metal aluminum silicate complex as a polishing agent with a refractive index between about 1.44 and about 1.47.

The liquid part of the vehicle constitutes about 50-94.5% by weight of the visually clear toothpaste, preferably about 55-80%. It contains a humectant, which consists wholly or for the most part (ie over 50%) of maltitol. Maltitol is essentially a glycosylsorbitol, i.e. 4-D- <1-D-glycopyranosyl-D-glucitol, having the structural formula: CHZOH CHZOH HO-ç fi HC ~ OH HO CH I CH ou It is prepared by hydrogenation of maltose. In a substantially pure form, it is a glassy solid. It dissolves easily in small amounts of water, and solutions thereof containing at least about 73% maltitol and up to about 27% water have been found to have a refractive index of about 1.48 (ie about 1.4750 to 1.4849) . When incorporated into a toothpaste together with separately added water having a refractive index of about 1.333, the liquid vehicle can be adjusted to have a refractive index of about 1.44 to about 1.48.

Typically, about 5 - 25% by weight of water can give this refractive index, with lower quantities giving a higher refractive index (eg about 1.47), and larger quantities of water, eg about 15 - 23%, give a lower refractive index (eg close to 1.44). 'rà- -. ~ .a .__ = .._ ,. Preferably, the refractive index of the liquid vehicle is about 1.44 - 1.47, and this is achieved with about 5 - 10% by weight of added water. The water content of the toothpaste refers to water that is added separately and does not refer to water that was used to dissolve the humectant.

Maltitol does not have to be pure in the sense that it is a sugar alcohol derivative of pure maltose. Commercial maltitol consists of maltitol containing minor amounts of sugar alcohol derivatives of maltotritose, maltotetros and closely related low molecular weight maltodextrin moieties of corn syrup and minimal amounts of D-sorbitol. Thus, a commercial "hydrogenated starch hydrolyzate" made from high maltose corn syrup can also be used in the practice of the present invention.

Maltitol has been recommended as useful in toothpaste, but not as an essential moisturizer in a visually clear toothpaste containing a polish.

With regard to this, reference is made to "Caries Research", vol 14, edition 2, (1980) pages 67 -74, Rundegren et al. (maltitol has been found not to contribute to demineralisation9) ï "Shiguku", vol 60, edition 6 (1973), pages 760 - 765, Matsuo (maltiol has been found not to be fermentable by Streptococcus salivarius, S.); "Acta Odont. Scand.", Vol 37, edition 2 (1979) pp. 103 - 115, Birkhed et al. and "Caries Research", vol 12, edition 3 (1978), pages 128 - 136, Birk- hed (observations made on plaque). “Acta Odont. Scand. ", Vol 35, edition 5 (1977), pages 257 - 263, Edwardsson et al. (Observations made on oral bacteria fl; Japanese patent specification 73 10241 by Sunstar (description of maltitol as a component in mouthwash). Maltitol can further be a component in the form of a variant of sorbitol, known as "non-crystallizing sorbitol", which can be used as a humectant in toothpaste. However, the main content of sorbitol in non-crystallizing sorbitol is such that a refractive index of about 1.48 cannot be obtained, so the possibilities of varying the composition of water / humectant decrease compared to what is the case according to the present invention.It has been noted that fatty acid esters of maltitol and other sugar alcohols are described as flavoring agents in toothpaste in British Patent Specification 2,038,182 to Lion Dentifrice Company If desired, the liquid vehicle of the visually clear toothpaste of the present invention may be g constitute a minor quantity (ie less than about 50%) of a humectant in addition to maltitol or even a non-humectant liquid vehicle component such as maltodextrin. Moisturizers, such as those previously mentioned, for example glycerol, sorbitol (typically a 70% solution of sorbitol), polyethylene glycol 400, polyethylene glycol 600 and the like, may be used. Preferably, maltitol constitutes more than about 50% by weight of the non-aqueous portion of the liquid vehicle, most preferably about 65-100%. Maltitol is typically present in the form of an approximately 73-85% solution, and is available from suppliers such as Aldrich Chemical Company, Merck and Co.

Inc., Imperial Chemicals Industries, Pfizer Inc., Lonza, Roquette Freres and Hayashibara Chemical Laboratories.

The complex of alkali metal aluminum silicate salt is the same as described above. It is generally of an alkaline nature, typically a sodium salt, and it effectively improves oral hygiene. It is an amorphous powder which further has the advantage that when incorporated into the vehicle its particles become substantially invisible.

The amount of alumina in the aluminosilicate is typically about 4 to 5% by weight and preferably about 1%. It is desirable that the refractive index of the aluminosilicate be within about 0.005 units and typically within about 0.001 units relative to the liquid vehicle.

As mentioned, the polish typically constitutes about 5 to 50% by weight of the toothpaste composition, preferably about 10 to 30% by weight.

The alkali metal-aluminum silicate salt complex appears to contain interlinked silica and alumina with Al-O-Si bonds, as described by Temele in "Chemistry of the Surface and the Activity of Alumina-Silica Cracking Catalyst", Discussion of the Faraday Society, No. 8, pp. 270 - 279 (1950) and in particular on page 273, Fig. 1, curve 3, where the interaction between silica and aluminum ions is potentiometrically demonstrated Other literature describing this type of complex is Milliken et al. "The Chemical Characteristics and Structures of Cracking Catalysts", Discussion of the Faraday Society, No. 8, 279 - 290 (1950) and in particular the text on pages 284 - 285. These complexes are clearly different from silica gel , as described by Plank et al., "Differences Between Silica and Silica-Alumina Gels I.

Factors Affecting the Porous Structure of These Gels ", Journal of Colloid Science, 2, pp. 399 - 412 (1947), and Plank," Differences Between Silica and Silica-Alumina Gels II. A Proposed Mechanism for the Gelation and Syneresis of These Gels ", Journal of Colloid Science 2, pp. 413 - 427 (1947), in which the formation of the Al-O-Si bond is described on p. 419 - 422. The aluminosilicate can be described as silica containing combined alumina.

As mentioned above, maltitol is described as useful in toothpaste in Japanese Patents 15120/65 (Patent Nos. 461,281) and 73/10241. The former does not include silicone-like polish; in the latter, silicic anhydride is stated as a polishing agent. However, it has been found that when silicic anhydride, such as colloidal silica xerogel obtainable from Grace Davison in the form of Syloid 74, is used in a visually clear toothpaste containing maltitol, the toothpaste quickly becomes cloudy in appearance and dries when exposed to air to a hard opaque product. When the aluminosilicate complex of the present invention is used, the toothpaste essentially maintains the desired clarity and rheology.

A fluorine-releasing alkali metal compound can be used in the toothpastes described herein. The fluorine-releasing alkali metal compound may be sodium fluoride, tin fluoride, tin chlorofluoride, potassium tin fluoride (SnF2-KF), lithium fluoride, ammonium fluoride and complex fluorides, such as potassium fluorosirconate, sodium hexafluorofluorane stannate and alkali metal fluoronate. These compounds have a beneficial effect on the care and hygiene of the oral cavity, for example, a reduction in the solubility of the enamel in acid and protection of the teeth against rot is obtained, which indicates a satisfactory content of soluble fluoride in the toothpastes according to the present invention. In particular, the content of monofluorophosphate ions in the form of fluoride in the alkali metal monofluorophosphates is quite high. The fluorine-containing compound is used in an amount which gives an effective non-toxic quantity of fluorine-containing ions in the toothpaste, typically about 0.01 - 1% by weight and preferably about 0.1% fluorine. Thus, sodium fluoride is typically present in an amount of about 0.02 - 2% by weight, preferably about 0.2%, and sodium monofluorophosphate, Na 2 PO 3 F, in an amount of about 0.1 - 7.6% by weight, preferably about 0%. 76%.

The alkali metal monofluorophosphates that can be used are sodium monofluorophosphate, lithium monofluorophosphate, potassium monofluorophosphate and ammonium monofluorophosphate. The preferred salt is sodium monofluorophosphate, Na 2 PO 3 F, which can vary considerably in the trade in terms of purity. It can be used in any suitable purity, provided that none of the fl kbnaunçuna does not significantly adversely affect the desired properties. In general, the degree of purity should be at least about 80%. In order to achieve the best results, it should contain at least 85% by weight and preferably at least 90% by weight of sodium monofluorophosphate, the remainder being primarily constituents or by-products of manufacture, such as sodium fluoride. water-soluble sodium phosphate salt and the like. In other words, the sodium monofluorophosphate used should have a total fluoride content of about 12%, preferably about 12.7%; a content not greater than 1.5% and preferably not greater than 1.2% of free sodium fluoride; and a sodium monofluorophosphate content of at least 12%, preferably at least 12.1%, all calculated as fluorine.

Other monofluorophosphate salts that can be used in the present invention are monofluoropolyphosphates such as Na4P3O9F, K4P3O9F, (NH4) 4P3O9F, Na3KP3O9F, (NH4) 3NaP3O9F and Li4P3O9F.

Any suitable flavoring or sweetening agent may be used to flavor the compositions of the present invention. Examples of suitable flavoring components are aromatic oils, such as oils of green mint, peppermint, evergreen, sassafras, cloves, sage, eucalyptus, marjoram, cinnamon, lemon and orange, as well as methyl salicylate. Suitable sweeteners are sucrose, lactose, maltose, sorbitol, sodium cyclamate, perillartine and saccharin. The suitable flavoring and sweetening agents may together constitute between about 0.01 and 5% or more of the compositions of the present invention. Chloroform can also be used. The sweeteners are less necessary when no anionic type surfactants are present, as the anionic substances give the toothpaste a slightly bitter taste.

Antibacterial agents may be included in the described toothpastes in a quantity of about 0.01 - 5% by weight. Typical antibacterial agents are: N1- (4-chlorobenzyl) -N5- (2,4-dichlorobenzyl) biguanide; p-chlorophenyl biguanide; 4-chlorobenzhydryl biguanide; 4-chlorobenzhydrylguanylurea; N-3-lauroxypropyl-N5-p-chlorobenzyl biguanide; 1,6-di-p-chlorophenyl-biguanidehexane; 1,6-bis (2-ethylhexyl biguanide) hexane; 1- (lauryl dimethylammonium) -8- (p-chlorobenzyldimethylammonium) octane dichloride; 5,6-dichloro-2-guanidinebenzimidazole; N1-p-chlorophenyl-N5-lauryl-biguanide; 5-amino-1,3-bis (2-ethylhexyl) -5-methylhexahydropyrimidine; and the non-toxic acid addition salts thereof.

Various other materials may be incorporated into the compositions of the invention. Examples thereof are coloring or bleaching agents or dyes, preservatives, silicones, chlorophyll compounds, ammonium-containing materials such as urea, diammonium phosphate and mixtures thereof, and also other constituents. The adjuvants are incorporated into the present compositions in quantities which do not adversely affect the desired properties and characteristics, and they are selected and used in appropriate amounts depending on the particular type of preparation in question.

Synthetic atomized fumed silica, such as those sold under the trademarks Cab-O-Sil M-5, Syloid 244, Syloid 266 and Aerosil D-200, may also be used in amounts of about 1 to 5% by weight to promote the thickening or gelling of the described toothpastes. 21 The toothpastes must have a pH value that is practically usable. A moderately acidic to alkaline pH is preferred.

The following particular examples further illustrate the type of toothpastes of the present invention, it being understood that the invention is of course not limited thereto. All amounts are by weight unless otherwise indicated.

Examples 1 and 2 The following toothpastes in the form of opaque gels were prepared: Example 1 2 Glycerol 10.0 10.0 Maltitol 15.0 15.0 Sodium aluminum silicate (silica 18.0 18.0 dioxide in combination with about 1% combined alumina) Zeo 49B (Huber) Pluronic 108 Segment Polymerate - 3.0 Sodium Lauryl Sulfate 1.0 - Xanthan 2.0 2.0 Polyox WSR 301 0.2 0.2 Sodium Monofluorophosphate 0.76 0.76 Titanium Dioxide 0.4 0.4 Weak Menthol flavor - 0.5 Peppermint oil, flavor 0.5 - Sodium saccharin 0.2 - Color solution (1%) 0.05 0.05 Water to 100 100 The toothpaste according to Example 1, containing sodium lauryl sulphate, has the desired foaming properties. The toothpaste according to Example 2 also has very good, stable and rich foam properties despite the fact that no anionic substance was added. The foam filled the entire oral cavity, with the desired mouthfeel, when the toothpaste was brushed on the teeth. Furthermore, it has no bitter taste despite the fact that a weak menthol flavor was present and no sweetener was added.

The toothpastes had a nice smooth texture and good appearance, they effectively removed stains and had acceptable tooth-grinding properties. They contained flocculated particles of sodium aluminosilicate.

The same desirable results were obtained when the xanthan of Example 2 was replaced with the low calcium xanthan of Example 1 of U.S. Patent 4,263,399.

A similar foam and the same mouthfeel were obtained when other block polymers of the polyoxyethylene and polyoxypropylene were used in place of Pluronic F-108, in particular Pluronic F 87.

Polyox WSR-301 is available from Union Carbide Corp. in the form of granules of water-soluble poly (ethylene oxide) resin with a molecular weight of about 4,000,000 and a Brookfield viscosity of 1650 - 3850 cp (25 ° c, spindle-1, speed 2 rpm), 1% by weight in water. Likewise, the same foaming and mouthfeel is achieved when other water-soluble poly (ethylene oxide) resins from Union Carbide Corp., such as Polyox WSR-N-10, WSR-N-80, WSR-N-750, WSR-N-3000, WSR -205 and WSR-1105, were substituted for Polyox WSR-301 in various concentrations.

The silica combined with alumina indicated in the examples was obtained from J.M. Huber, Corp., Havre de Grace, Maryland, in the form of Zeo 49 (A or B).

Examples 3 - 6 The following clear gels (Examples 3 and 4) and opaque gels (Examples 5 and 6), useful as toothpastes, were prepared: »__ Ä w 453 4595 23 Example 3 4 5 6 Glycerol 10.0 _ 10.0 _ Sorbitol 16.0 - “15.0 - Maltitol (active) 16.0 35.0 15.0 30.0 Sodium aluminosilicate 22.0 18.0 18.0 18.0 (silica in combination with alumina) Pluronic F-108 3.0 3.0 5.0 - Pluronic F-87 - - - 3.0 Xanthan 1.5 2.0 2.0 2.0 Polyox WSR-301 0.2 0.2 0.2 0.2 Sodium monofluorophosphate 0.76 0.76 0.76 0.76 Titanium dioxide - - 0.4 0.4 Weak menthol flavor 0.5 0.5 0.5 0.5 Color solution (1%) 0.05 0.05 0, 05 0.05 Water QS to 100 100 100 100 The toothpastes of Examples 3 and 4 were clear and those of Examples 5 and 6 were opaque. They had a smooth texture. All four had a very good stable full-bodied foam, the toothpaste according to Example 5 having a foam which was more full-bodied than the toothpastes according to Examples 3 and 4. A larger amount of foam was obtained with the toothpaste according to Example 6. All the foams gave a satisfactory mouthfeel in the entire oral cavity during toothbrushing. No bitter taste was noted. The toothpastes effectively removed stains and had acceptable tooth-grinding properties. They contained flocculated particles of sodium aluminosilicate.

Examples 7 - 11 The following toothpastes were determined: 7 8 9 10 11 Melting oil (active) 30.0 30.0 30.0 30.0 30.0 Sodium aluminum silicate 12.0 12.0 12.0 18.0 15.0 (silica in combination with alumina) Calcined alumina 5.0 5.0 5.0 5.0 2, Pluronic F-108,,, 3.0 3, Xanthan 2.0 2.0 2.0 1.7, Polyox WSR- 301 0.2 - - 0.2, 2 WSR-1105 - 0.2 - - - WSR-N-750 - - 1.0 - - Sodium monofluorophosphate 0.76 0.76 0.76 0.76 0.76 Titanium dioxide 0.4 0.4 0.4 0.4 0.4 Weak menthol flavor 0.5 0.5 0.5 0.5 0.5 Water QS; to 100 100 100 100 100 The toothpastes according to examples 7 - 11 had a great cleansing effect and gave a good stable and full-bodied foam. They had a smooth consistency, with the toothpastes of Examples 7, 10 and 11, which contained Polyox WSR-301, having the best consistency. All the foams gave a desired mouthfeel in the entire oral cavity during toothbrushing. No bitter taste was noted.

They effectively removed stains and had acceptable tooth-grinding properties. They contained flocculated particles of sodium aluminosilicate.

Examples 12 - 15 The following toothpastes were prepared: Example 12 13 14 15 Glycerol 10.0 10.0 10.0 10.0 Sorbitol 15.0 15.0 15.0 15.0 Maltitol (active) 15.0 15.0 .0 15.0 Dicalcium phosphate dihydrate 30.0 30.0 15.0 15.0 415.3 459 '25 12 13 14 15 Anhydrous dicalcium phosphate - - 10.0 - Calcined alumina - - - 10.0 Pluronic F-108 3.0 3 .0 3.0 3.0 Xanthan 2.0 2.0 2.0 2.0 Polyox WSR-301 - 0.2 0.2 0.2 Sodium monofluorophosphate 0.76 0.76 0.76 0.76 Titanium dioxide 0 .4 0.4 0.4 0.4 Weak menthol flavor 0.5 0.5 0.5 0.5 Water QS to 100 100 100 100 The toothpastes according to examples 12 - 15 gave good stable and full-bodied foam. The toothpastes according to Examples 13-15 (which contained Polyox material) had a particularly fine and smooth consistency. All gave a foam with the desired mouthfeel in the entire oral cavity during toothbrushing. Even if no sweetener was used, they had a rather sweet taste.

Examples 16 - 17 The following opaque toothpaste gels were prepared: 912335 Maltitol (75% solution) 40.00 40.00 Sodium aluminum silicate (silica 18.00 18.00 containing about 1% combined alumina - Zeo 49B - Huber) Pluronic F-108 block polymer 3.00 3.00 Xanthan 1.70 1.70 Polyox WSR 301 (Union Carbide) 0.20 - Titanium dioxide 0.40 0.40 Flavor 0.50 0.50 Sodium saccharin 0.20 0.20 Deionized water QS to “100 100 26 Both toothpastes gave a stable full-bodied foam with a good mouthfeel; the mouthfeel of the toothpaste was especially satisfying.

When compared for the ability to remove stains on the teeth and the dentin abrasive properties, the toothpaste of Example 16, containing the Polyox material, removed more stains under less dentin abrasion than the toothpaste of Example 17 without Polyox. -material. In the toothpaste of Example 17, flocculating particles of sodium aluminosilicate formed in situ.

The results were as follows: Toothpaste Stain removal Radioactive den-% tin abrasion (RDA) A 35 14 B 22 39 In a stain removal examination, human tooth enamel was treated with 0.1 N HCl for 2 minutes, then rinsed with water, soaked with a dilute solution of tin fluoride, dried and finally subjected to a gas stream of hydrogen sulfide, which resulted in the deposition of a brown deposit of tin sulfide. The amount of deposition on the surface was measured with a 'Gardner Automatic Color Difference meter. The surface was then brushed with a mechanical brushing machine under reciprocating motion 500 times with a slurry of a toothpaste, and the remaining stain was measured by the measuring instrument. The remaining stain was finally completely removed with dental pumice and the reflection factor of the tooth was determined. The possibility of a toothpaste to remove the stain is indicated by the following equation: 27 (Rd H - Rd. H. 100 Stain removal in%: 500 movements from the beginning) Rd pumice - Rd from the beginning treated in Which Rd from the beginning 'Rd500 movements and Rdpip pumice treated denotes the reflection values measured on the initially stained surfaces, after brushing with 500 reciprocating movements and after removal of the remaining stain by rubbing with pumice.

The RDA values were obtained by applying a method based on a radioactive technique described in the literature; Stookey, C.K. and Muhler, J.C., J. Dental Research 47, 524-538 (1968).

Example gel 18 The following toothpaste was prepared and compared with the toothpaste of Example 10. 2 Maltitol (75% solution) 40.00 (30.00 active) Sodium aluminosilicate (silica containing 18.00 containing about 1% combined alumina - Zeo 49B-Huber) Calcined alumina 5.00 Pluronic F-108 3.00 Xanthan 1.70 Titanium dioxide 0.40 Flavor 0.50 Sodium saccharin 0.10 Deionized water QS to 100 The toothpastes of Examples 10 and 18 both gave a stable full-bodied foam with a good mouthfeel; particularly satisfying was the mouthfeel obtained by the toothpaste A.

The following results with respect to stain removal and radioactive dentin abrasion were obtained with the toothpastes of Examples 10 and 18, which results show that the toothpaste of Example 10 containing Polyox material was superior with respect to stain removal at almost the same dentin abrasion.

Toothpaste Stain removal in% RDA 10 65 47 18 44 41 Although the invention has been described with reference to illustrative examples, it is of course obvious to those skilled in the art that various modifications may be made without departing from the scope of the invention.

Claims (9)

453 459 29 P a t e n t k r a v Toothpaste, characterized in that it contains 20 to 80% by weight of a liquid humectant, 0.5 to 7% by weight of xanthan gum and 1 to 10% by weight of a nonionic polyoxyethylene-polyoxypropylene polymerate as the only surfactant. Toothpaste according to claim 1, characterized in that resinous poly (ethylene oxide) is present in an amount of 0.1 - 5% by weight. Toothpaste according to claim 1 or 2, characterized in that the block polymer is a solid material. Toothpaste according to claim 3, characterized in that the solid block polymer contains 80% by weight of the polyoxyethylene, wherein the molecular weight of the polyoxypropylene is about 3250 or 70% by weight of the polyoxyethylene, the molecular weight of the polyoxypropylene being 2250. Toothpaste according to claim 2, characterized in that 1.5 - 3% by weight of xanthan and 0.1 - 1.5% by weight of resinous poly (ethylene oxide) are present. Toothpaste according to any one of claims 1 or 2, characterized in that the liquid moisturizing vehicle comprises glycerol, sorbitol, maltitol or mixtures thereof. Toothpaste according to claim 6, characterized in that maltitol is present as the humectant and that the toothpaste contains 5 - 50% by weight of an alkali metal aluminum silicate complex as a polishing agent, which toothpaste is visually clear. 453 459 30 Toothpaste according to claim 2, characterized in that it contains 5 - 50% by weight of a silica-containing polish. Toothpaste according to claim 8, characterized in that the silica-containing polishing agent is an alkali metal-aluminum silicate complex.