CH657775A5 - METHOD FOR PRODUCING AN AGGLOMERED PARTICLE-CONTAINING DENTAL CARE AND DEVICE FOR CARRYING OUT THE METHOD. - Google Patents

Abstract

Functional agglomerated speckles, for incorporation in dentifrices, include agglomerates of a water insoluble powdered functional material and water insoluble, ethanol soluble ethyl cellulose, and may sometimes preferably also include a water soluble binder, such as polyvinyl pyrrolidone. Such speckles satisfactorily maintain their integrity and identity during processing of the dentifrice after addition of the speckles to a main dentifrice body but on storage, after packaging of the dentifrice in dispensing tubes, soften sufficiently so as to become essentially impalpable to one utilizing the dentifrice in brushing his teeth. Despite such softening the speckles continue to maintain their identity as speckles in the dentifrice. The speckles are especially useful in translucent or transparent gel dentifrices which contain components, such as flavouring and surface active agents, which may controllably soften the speckles on storage.

Description

The invention relates to a method for producing a dental care product containing agglomerated particles and to an apparatus for carrying out the method.

The mentioned agglomerated functional particles present in the dentifrice contain a water-insoluble powdery functional material, such as a tooth polishing agent, and water-insoluble, ethanol-soluble ethyl cellulose, preferably together with a water-soluble binder, such as polyvinylpyrrolidone. The dentifrice is preferably contained in translucent or transparent containers so that the agglomerated particles in the dentifrice can be recognized from a translucent or transparent gel. In order to achieve desired visual effects, the particles usually have a color that stands out from the usual dentifrice.

Toothpastes and gels that contain color-contrasting particles are already known. Although in some cases these particles are primarily intended to achieve an aesthetic effect, they can contain functional components such as polishing agents. Various dentifrices are also known that contain particles that are initially palpable but become imperceptible during tooth brushing. Although these products have received approval, it has proven desirable to bring another type of speckled dentifrice onto the market in which, like the dentifrice that can be made according to the invention, the particles, although easily recognizable and separate, are from the beginning and are also imperceptible during brushing.

Dental care products, the visible and tangible, essentially water-insoluble, agglomerated particles of polishing

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mittein contain have already been described. Binders have also been used to make such particles, and methylcellulose and polyvinylpyrrolidone (PVP) have been mentioned among the water-soluble binders. However, methyl cellulose is water-soluble and therefore does not result in particles that remain intact during the lengthy processing. A dentifrice that contains encapsulated sweeteners has also been described. As a coating for the sweetener to form beads, ethyl cellulose has been found useful among a variety of other materials. Water-soluble and water-insoluble binders for particles for incorporation into dentifrices have already been mentioned together, but no mention was made of ethyl cellulose. Formulations for toothpastes which contain dispersed visible agglomerated particles of tooth polishing agent have also already been stated, the advantages of both water-soluble and water-insoluble agglomerating or binding agents being recognized, but ethyl cellulose has not been proposed as a binding agent. Finally, the encapsulation of sodium fluoride in microcapsules from lower alkyl cellulose, such as ethyl cellulose, and the dispersion of these capsules in a dentifrice is known. However, this did not result in any proposals for the agglomeration of materials for the production of particles for incorporation in dentifrices.

Ethyl cellulose, which is insoluble in water but soluble in ethanol, is used as an agglomerating agent for a functional, water-insoluble powdery material for producing particles with improved properties for incorporation in dentifrices.

The known agglomerated particles made with water-soluble binders such as methyl cellulose can disintegrate during processing after being mixed into the other components of the dentifrice, such as gels or pastes previously formulated, if the speckled dentifrice containing the particles is held in the processing device for too long what can happen if mechanical malfunctions lead to device failure. Such impairment of the particles can occur because the dentifrices contain water, which can dissolve the water-soluble binders of the aggregated particles and lead to a separation of the individual particles of the aggregates. In such cases, the solution of the binder can be kept to a minimum by immediate processing. However, if there are stagnations and thus longer processing times, product losses can be caused. Aggregate particles for dentifrices, which are prepared with binders insoluble in ordinary water, but as are known without reference to the use of ethyl cellulose, can be felt after their dispersion in dentifrice gels or pastes. Although this may often be desirable, for some dentifrices, e.g. B. not for those for use by people with sensitive gums.

With the ethyl cellulose contained in the agglomerated particles as a binder, the integrity of the aggregated particles in aqueous dentifrices which can be produced according to the invention is maintained for a sufficient time to enable processing after incorporation of the aggregated particles into the dentifrice. Presumably due to the presence of components in the dentifrice that appear to soften the aggregated particles during storage, such as flavors and, in some cases, surfactants, the aggregated particles in the dentifrice are softened sufficiently during storage so that, although as such, they remain intact

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and remain separate in appearance until the product is used, imperceptible and easily disintegrating when brushing teeth.

In some preferred formulations, e.g. Those that may contain minor amounts of flavors (and dentifrices as well as other solvents or lipophilic substances), or in dentifrices that contain materials with lower solubility (for the ethyl cellulose), the presence of an auxiliary binder that is soluble in water, e.g. of polyvinylpyrrolidone lead to the desired imperceptibility. Even then, the aggregated particles remain intact due to the presence of the ethyl cellulose.

Once made, preferably in a process in which a water-insoluble functional material in powder form (or a mixture of the functional powder and a water-soluble binder) is "moistened" with a solution of the water-insoluble ethyl cellulose in a volatile solvent, compacted, in particulate form transferred and then dried, the aggregated particles can be directed to a stream of dentifrice in a controlled form, adhered to it and evenly distributed, preferably using certain devices.

The functional agglomerated particles for incorporation in dentifrices consist of agglomerates of a water-insoluble powdery functional material and water-insoluble, ethanol-soluble ethyl cellulose, sometimes with a water-soluble binder.

The functional agglomerated particles contain two essential components, namely a water-insoluble powdery functional material and water-insoluble, ethanol-soluble ethyl cellulose. The first is the functional imparting material and the second the binder. Numerous functional materials, all of which are insoluble or at least slightly soluble in water, can be used, including coloring substances such as pigments, germicides, ion exchangers, polymeric materials, (which may contain other active components, sometimes water-soluble substances) and flavors. However, it is preferred that the functional base material for the agglomerated particles is a polishing agent or contains a larger proportion thereof. Of the polishing agents that are normally used in dry powder form for the production of the agglomerated particles, the following are preferred: dicalcium phosphate, tricalcium phosphate, insoluble sodium metaphosphate, aluminum oxide, silicon dioxide, magnesium carbonate, calcium carbonate, calcium pyrophosphate, bentonite and zirconium silicate and suitable mixtures of these substances. Both anhydrous or calcined forms of these materials, such as calcined alumina, and hydrated forms, such as dicalcium phosphate dihydrate, can be used. However, the anhydrous or calcined materials are often preferred. Since the agglomerates are usually in the desired opaque form, it is not necessary that their refractive indices match those of the wearer (including other components) for the dentifrice. However, «transparent» polishing agents with such a refractive index of e.g. 1.44 to 1.47 can be used to obtain transparent or translucent agglomerated particles which can be used to prepare a clear gel dentifrice containing polish. Such “transparent” polishing agents preferably include colloidal silicas and those sold under the trademark Syloid, as Syloids 63, 65, 72 and 74, as well as under the trademark Santocel, as Santocel 100 and as Zeo 49, 113 and 119 and as Zeodent. Synthetic alkali metal aluminosilicate complexes can also be particularly useful because their refractive indices are very close to those of the dentifrice carrier, including water, glycerin, sorbitol and gelling agents normally used in the manufacture of dentifrices.

The water-insoluble, powdery functional material used to prepare the agglomerated particles normally has a particle size of 0.5 to 20 µm, preferably 1 to 10 µm and especially 2 to 8 Jim. In some cases, however, larger particles can be used, e.g. if a reduction in particle size occurs during agglomeration, as can be the case when mixing before the actual agglomeration.

The binder for the agglomerated particles is ethyl cellulose. This effective binder is insoluble in water, but is soluble in ethanol and gradually soluble in an aqueous glycerol sorbitol medium which also contains “solvents” for it, such as flavorings and surface-active agents which are usually contained in dentifrices according to the invention. This ethyl cellulose usually has an ethoxy content of about 45 to 50%, preferably 48 to 50% or 48 to 49.5%. In a preferred ethyl cellulose, as sold by the Dow Chemical Company under the trademark Ethocel Standard 10 Premium Ethyl Cellulose, the ethoxy content is 48.0 to 49.5%, the viscosity is 0 to 1110_3Pas, the moisture content is a maximum of 2%, the chloride content as NaCl is a maximum of 0. 15% and the ash content maximum 0.15%.

Ethyl cellulose resins, which are suitable as binders for the agglomerated particles mentioned, are commercially available as white to light yellow-brown granular powders with a degree of etherification of 2.25 to 2.58 ethoxy groups per anhydroglucose unit, which has an ethoxy content of 45. Corresponds to 0 to 49.5% by weight.

Preferred materials have an ethoxy content of 48.0 to 49.5% by weight, less preferred materials an ethoxy content of 45.0 to 46.5%. Of course, these products are available in various viscosities, usually from 3 to 110 10 -3 Pas, with the more viscous materials being less preferred. The preferred or "standard" quality of ethyl cellulose is soluble in aromatic hydrocarbons, hydroaromatic hydrocarbons, chlorinated aliphatic hydrocarbons and Naval substances. It is also soluble in monohydric aliphatic alcohols such as ethanol; in monohydric cyclic alcohols such as benzyl alcohol, phenylethyl alcohol and pine oil; in ether alcohols, such as glycol ethers; in ethers, such as diethyl cellosolve, in esters, especially acetates, such as isopropyl acetate and sec. Amyl acetate and esters of hydroxy acids, such as methyl salicylate, and ketones, such as cyclohexanone and acetophenone. In general, the less preferred "medium" ethoxy ethyl cellulose is less soluble than the standard grade, which may be more appropriate when larger amounts of solubilizing materials are included in the dentifrice formulation.

The water-soluble additional binders which can preferably be used for the binder combination and which are sometimes used for the production of the agglomerated particles mentioned include, inter alia, Gum arabic gelatin, natural and modified starches, alkali metal carboxymethyl cellulose, especially sodium carboxymethyl cellulose, polyethylene glycols, sugars such as glucose and sucrose, methyl cellulose, carboxyethyl hydroxyethyl cellulose, alginates, especially sodium alginate, polyvinyl alcohol, carrageenan, preferably irish gum, preferably irish moss,

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Tragacanth and PVP. It has been found that PVP is stable in the presence of ethyl cellulose, does not bleed excessively from the agglomerated particles into which it is incorporated as a binder in combination with the ethyl cellulose and can be used to adjust the binding properties of the combination binder so that it is easy to use can be adapted in the same desired total amount for use in a variety of formulations for dentifrices, the proportion of ethyl cellulose to the PVP being able to be varied accordingly. It is also important that the combination binder in the agglomerated particles is sufficiently hard and firm that they do not dissolve excessively during processing of the agglomerated particles and nevertheless soften sufficiently during storage of the dentifrice into which they are incorporated so that they when the dentifrice is used are imperceptible. However, they do not soften so much that they form stripes in the tube or during squeezing. By changing the ratio of ethyl cellulose to PVP by increasing the proportion of PVP, however, controlled streaking can sometimes be achieved if desired.

The preferred PVP used usually has a molecular weight of 30,000 to 50,000, and preferably about 40,000. Such a product, sold by GAF Corporation under the Plasdone trademark, as Plasdone K 29 to 32 and K 26 to 28, has average molecular weights denoted by K values, where K-30 indicates an average molecular weight of about 40,000. The PVP is available as a light colored powder with a moisture content of less than 5%, a nitrogen content of 12.6 + 0.4%, an arsenic content of less than 2 ppm and a heavy metal content of less than 20 ppm. It is soluble in cold water and in a variety of organic alcohols, acids, ether alcohols, ketone alcohols, chlorinated hydrocarbons, esters and ketones, but is insoluble in hydrocarbons and some ethers, chlorinated hydrocarbons, ketones and esters. It is compatible with numerous natural and synthetic resins, inorganic salts and many synthetic organic surfactants, including those commonly used as dental cleaners, e.g. Sodium salts of higher fatty alcohol sulfates and poly lower. alkoxylated alcohol sulfates.

Although one would have expected the best agglomerated particles to be obtained with the least soluble binders, it has been found that the ethyl cellulose as described herein gives agglomerated particles with ideal properties that are intact and separated during processing and storage are preserved from each other, but are essentially imperceptible when brushing the teeth with the dentifrice. If desired, the properties of the agglomerated particles can be changed, e.g. B. by modifying the ethoxy content of ethyl cellulose and / or by mixing it with other known water-insoluble binders. Similarly, if the level of lipophilic materials in the dentifrice is low so that the agglomerated particles are unlikely to become imperceptible on storage, water soluble binders, e.g. PVP can be used together with the ethyl cellulose to improve the softening of the agglomerated particles. Such a change in the properties of the agglomerated particles can also be achieved by using more water-soluble binder (s) or more of this binder (s) or by changing the molecular weight, e.g. by reducing the molecular weight of the PVP. The properties of the agglomerated particles can also be changed by varying the proportions of the functional material and the binder, as indicated below. Thus agglomerates can be produced which are stable during processing after mixing, e.g. during deaeration and filling, but break apart quickly after the toothpaste has been squeezed out of its container or, if desired, this breakup can be delayed so that the agglomerates feel harder and somewhat firmer during tooth brushing. Normally, however, it is preferred that the agglomerated particles are essentially imperceptible when in use, but are intact in the dentifrice.

The binder normally has a particle size like that of the functional powdery material of the agglomerated particles, in particular if the agglomerates are to be produced at least in part by compressing the powdery material. Since the agglomerated particles are normally produced using the alcoholic solution of ethyl cellulose, their particle size is of relatively little importance. However, if water-soluble binder is preferably present, it should be borne in mind that its particle size is preferably the same as that of the functional material.

The agglomerated particles, which are sometimes white or colorless and possibly even translucent or translucent or come close to such an appearance, can also be colored, usually due to an appropriate level of dye or pigment or a mixture of dyes and / or pigments. Any non-toxic dye or pigment with a suitable color, usually a strong color, e.g. an appropriate hue with a Munsell color strength greater than 4 and a Munsell value in the range 4 to 7 can be used, and in some cases soft colors or pastel tones may be satisfactory or desirable. It is usually best to use a dye or pigment that is approved for pharmaceuticals and cosmetics (D&C) or for food, pharmaceuticals and cosmetics (FD&C).

Representative examples of suitable dyes are D&C Red Nos. 2,3,6, 7, 8,9,10, 11,12,13,19, 30, 31, 36 and 37; D&C Blue No. 1; FD&C Blue Nos. 1 and 2; FD&C Red Nos. 1,2 and 3; FD&C Yellow No. 5; cosmetic green oxide and cosmetic red oxide. Pigments of the aforementioned dyes, known as pigment colors, are also suitable for coloring the agglomerated particles, but dyes are normally preferred. The pigments mentioned often consist of dyes on fine, powdery, insoluble supports and the pigments are dispersed in the medium to be colored rather than dissolved. The particle sizes of the pigments used can be in the range given above for the polishing agents or in the particle size range of the binder. The particle sizes can be finer, e.g. is in the range of 0.01 to 1 µm. The particle sizes of the dyes can be similar. However, since these are normally in the dissolved state, in water or in a solvent, which is preferably oil-soluble, the particle sizes are not important as long as the powder or the particles are small enough to easily dissolve the dye in the selected solvent.

The agglomerated particles mentioned, which are contained in the dentifrice that can be produced according to the invention, can be produced by any suitable method, either in a wet or in a dry process. If ethyl cellulose is the only binder and wet granulation is used, it is preferable to mix 5

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first, the ethyl cellulose in dry powder form with the polishing agent and the dye or pigment, if used, and ethanol. Water and / or a lipophilic solvent may be present with the ethanol, and a dye or pigment for coloring the agglomerated particles may also be present. Alternatively, and often preferred, the polishing agent is mixed into an ethanol solution of the ethyl cellulose, which may contain a suitable dye or pigment. The proportions of the components are such that agglomerated particles with the desired composition are formed and the proportion of solvent (s) normally makes up 5 to 50% of the mixture, preferably 5 to 25%. The dispersion can be prepared in a Hobart mixer, a Dravo pan or other suitable mixing device or in a granulating device for the wetting of powder (s), the order of addition of the various components of the dispersion being able to be adjusted in such a way that the best functioning of the mixing device is achieved. A preferred method of producing the agglomerated particles is to press the "moistened" mixture of polishing agent and ethyl cellulose (with dye or pigment, if used) through a sieve with regular openings, usually about 0.150 to 2.00 in size mm, and the "squeezed" agglomerates then dry, usually in the air or in an oven. Instead of sieves, other devices, such as press extrusion, can be used to convert the mixture into pellets, after which the particles formed are dried. These are then classified, normally according to a mesh size of 2.00 to 0.177 mm, preferably 0.420 to 0.177 mm and in particular 0.595 to 0.25 mm. If the granulation e.g. done in a Dravo pan, the pressing through a sieve or the extrusion can of course be avoided. At particle sizes greater than 2.00 mm, these are generally unsatisfactory for insertion into a consumer's oral cavity, and when the size is less than about 0.177 mm, they are not easily recognizable and therefore not so attractive in appearance.

Instead of wet granulation, a dry process can be used, in which the components of the agglomerated particles are pressed into a large tablet which can then be broken up, whereupon particles of the desired size are separated from one another. In such a tableting process, it may be desirable to use a water-insoluble lubricant, such as talc, magnesium stearate, calcium stearate or stearic acid, which also supports agglomeration. Such materials and other water-insoluble adjuvants can also be added when wet granulation is used. The agglomerates so produced are preferably dry and contain no moisture, however a moisture content of up to 10%, e.g. from 1 to 5% without causing serious adverse effects on the properties of the agglomerated particles.

The proportions of water-insoluble powdery functional material, such as tooth polish and binder, namely ethyl cellulose or ethyl cellulose plus water-soluble binder, are usually such that the binder makes up the smaller proportion and the powdery functional material makes up the larger proportion of the agglomerated particles, but other materials, how dyes and auxiliaries can also be present. In general, the amount of the tooth polishing agent or the functional material is 75 or 80 to 98% of the agglomerates, preferably 85 to 97%, the amount of the binder or the combined binders is 2 to 20% and preferably 3 to 15% of the agglomerates and the amount of Dye 0 to 5%, e.g. about 0.05 to 1% of the agglomerates, all on a dry basis, without water and ethanol or other solvent. If a combination of binders is present, the ratio of ethyl cellulose to water-soluble binder (PVP) is in the range from 1:10 to 10: 1, preferably from 1: 5 to 5: 1, in particular from 1: 2 to 2: 1 and everything from 1: 2 to 1: 1, e.g. 2: 3.

The dentifrice that can be produced according to the invention, in which the agglomerates are distributed, can consist of any suitable product, since it primarily serves as a medium for the agglomerates, which keeps them in the individual and separate state, and thereby performs its normal functions. Opaque dentifrices are useful media for the agglomerates described, but preference is given to transparent or translucent dentifrices, which are normally characterized as a gel. The dentifrices that can be produced according to the invention contain water, a humectant, a gel-forming agent, tooth cleaning agents, flavorings, and tooth polishing agents, usually together with dyes. The numerous preferred functional auxiliaries include, in particular, fluorides, stabilizers, anti-caries agents and antibacterial compounds.

The water used to make the dentifrice is preferably deionized water, although city water, both hard and soft, can be used. The gelling agent normally consists of a water-soluble natural or synthetic rubber or rubber-like material, which includes carra-gees, ragant gum, xanthan gum, alginates, alkali metal carboxymethyl cellulose, preferably sodium carboxymethyl cellulose, hydroxymethyl carboxyethyl cellulose, polyvinyl pyrrolidone, starch and hydrophilic colloidal colloidal polyoxides as sold under the trademark Car-bopol 934 and 940. Although numerous polyols can be used as humectants, those having 3 to 6 carbon atoms and 3 to 6 hydroxyl groups per molecule are preferred, and the humectants of choice are glycerol and sorbitol. Glycerin, generally with a purity of about 99% or more, is liquid in its normal state and sorbitol, a solid, is often used as a 70% aqueous solution (70% sorbitol, 30% water). The three components mentioned can be regarded as the main components of the carrier for the dentifrice, into which flavorings and cleaning agents can also be incorporated. The detergent may comprise a soap, but is usually a synthetic organic surfactant with cleaning properties that is not a soap. This cleaning agent is preferably anionic, although nonionic cleaning agents can also be used. Ampholytic detergents can be used and cationic detergents are acceptable under certain circumstances.

Anionic detergents are particularly useful because they combine excellent cleaning properties and foam-producing properties. Normally these compounds contain hydrophilic and lipophilic groups in a balanced manner, the lipophilic group usually being a higher fatty alkyl or acyl group having 10 to 18 carbon atoms, preferably 12 to 16 carbon atoms and the hydrophilic group an alkali metal, e.g. Sodium, potassium, an ammonium or lower alkanolammonium group. Suitable anionic detergents are: what5

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serially soluble salts (usually alkali metal and preferably sodium or potassium salts) of higher fatty acid monoglyceride sulfates such as the sodium salt of the monosulfated monoglyceride of hydrogenated coconut oil fatty acids; higher alkyl sulfates such as sodium lauryl sulfate; Alkylarylsulfonates such as the sodium salt of linear dodecylbenzenesulfonate; higher alkyl sulfoacetates; higher fatty acid esters of 1,2-dihydroxypropane sulfonates; Sodium salts of sulfated polyethoxylated alcohols and the substantially saturated higher aliphatic acylamides of lower aliphatic aminocarboxylic acid compounds such as N-lauroyl sarcosine and the sodium, potassium and ethanol amine salts of N-lauroyl, N-myristoyl and N-palmitoyl sarcosine all of these sarcosine compounds preferably being substantially free of soap or similar higher fatty acid materials. Of the nonionic detergents are ethoxylated sorbitan monostearate with about 20 moles of ethylene oxide per mole; Condensation products of ethylene oxide, propylene oxide and propylene glycol (Pluro-nics); polyethoxylated higher fatty alcohols such as the neodols (e.g. 23-6.5 and 45-11); Condensation products of a-olefin oxides with 10 to 20 carbon atoms, polyhydric alcohols with 2 to 10 carbon atoms and 2 to 6 hydroxyl groups and either ethylene oxide or mixtures of ethylene oxide and propylene oxide are useful. Quaternized imidazolyl derivatives such as Miranol C2M and other Mirande are useful amphoteric detergents, and the quaternary ammonium halides such as dimethyldicetylammonium bromide are cationic detergents.

The various polishing agents which can be dispersed in the carrier for the dentifrice or in the carrier plus cleaning agent plus other auxiliaries are preferably those described above for the conversion into agglomerates. Also useful are synthetic, finely divided silicas such as those sold under the trademarks Cab-O-Sil M-5, Syloid 244, Syloid 266, Aerosil D-200, Zeosyl 200 and Zeothix 265, which normally only contain a small percentage of the polishing agent are used, and usually make up no more than 1 to 9% by weight of the total dentifrice, and are useful for thickening or transferring the carrier into a gel and improving the clarity of the dentifrice.

The dental care products which can be produced according to the invention contain flavorings; they can also have sweetening materials. Examples include flavoring oils such as spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyptus, cinnamon, lemon and orange oils, preferred sweeteners are sucrose, lactose, maltose and saccharin . Preferred fluoride-containing dentifrices advantageously contain sodium fluoride, tin (II) fluoride, potassium fluoride, potassium tin (II) fluoride, sodium hexafluorostanate, tin (II) chlorofluoride and / or sodium monofluorophosphate.

The flavors usually include a variety of essential oils, mainly terpenes; Esters, alcohols, aldehydes, ketones and other aromatic substances, many of which exude an aromatic smell and fragrance. Since the taste results from the simultaneous physiological and psychological reaction of a substance in the mouth and is determined by the taste, smell and feeling, the smell being of primary importance, it is not surprising that aromatic materials are important components of flavorings. Benefit from this fact and the chemical nature of these materials, since, as stated above, ethyl cellulose binder slowly dissolves in the agglomerates described and thus leads to a softening of the agglomerates but not to their disintegration. For example, the terpenes, which are hydrocarbons and an important class of perfume or fragrance,

good solvents for the ethyl cellulose contained in the particles, as many other fragrances as those previously mentioned as flavoring oils, and others known in the field of perfumes and fragrances. The aromatic essences are contained in the dentifrices that can be produced according to the invention in order to soften the ethyl cellulose in the agglomerates and thereby make them imperceptible. It is not necessary to add another component to the dentifrice or agglomerates for this purpose. Because of the relatively small amount of flavoring agent normally contained in a dentifrice, the amount of the lipophilic portion of the flavoring agent often being even smaller, a desired slow softening of the agglomerated particles can occur, usually due to the relatively low mass transfer rate for the "solvent" , which is particularly low due to the gelatinous nature of the dentifrice. Thus, even if some flavoring material at the agglomerate interface begins to soften the ethyl cellulose while the dentifrice is being mixed, the ethyl cellulose solution in the flavoring will soon be saturated, preventing further rapid dissolution of the ethyl cellulose. Also during the period in which a dentifrice is normally stored prior to sale and use, which is often at least about 2 weeks and sometimes more - for certain dental care formulations it is desirable to age them in order to improve the taste and uniformity of the product To improve, the agglomerates become imperceptible, but remain intact and separate.

Sometimes, in addition to the ethyl cellulose binder, there may also be a water-soluble binder such as PVP. In this product, the ethyl cellulose holds the agglomerate together until it is made "soluble" in the dentifrice by the lipophilic components. The preferred use of PVP allows less ethyl cellulose to be used and facilitates the desired softening of the agglomerates in dentifrices that contain less solubilizing flavorings and other lipophilic ingredients.

Although the flavoring substances, in particular the lipophilic flavoring substances, which have a substantial dissolving effect on the ethyl cellulose, are the most important slowly dissolving components of the dentifrices which can be produced according to the invention, the surface-active agents which have a lipophilic fraction can likewise have a noticeable solubilizing effect and because of their wetting effect promote the mass transfer in a toothpaste tube and thereby improve the dissolution rate of the ethyl cellulose. It is also possible that combinations of the other components of the dentifrice, including some sweeteners and carrier components, support the solution of the ethyl cellulose to the desired extent without promoting premature softening of the agglomerates.

Coloring substances, such as those listed above with respect to the agglomerates, can be used, usually in a lesser amount, to provide a matrix that contrasts with the agglomerates. Numerous other adjuvants may also be present in the dentifrice, including preservatives, silicones, chlorophyll compounds, and ammoniated materials. Usually, when a gel dentifrice is made, it becomes translucent or translucent

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should be selected, a polishing agent whose refractive index largely matches the rest of the medium of the dentifrice. Of course, in such clear gel formulations, the amount of insoluble materials that would cause the gel to cloud is usually kept to a minimum. If e.g. the pH of the dentifrice is adjusted, the pH is advantageously in the range from 3 to 10, better in the range from 3.5 to 5 if tin (II) ions are present, and in the range from 4.5 to 7 If such ions are not present, organic acids such as citric acid, malonic acid and fumaric acids can be used.

In the dentifrices that can be produced according to the invention, a tooth polishing agent is usually evenly distributed in the carrier composed of water, humectant and gel-forming agent, which already contains the tooth cleaning agent and the desired amount of aroma substance. Then the agglomerates, which preferably also contain a polishing agent and often a different one than that contained in the base composition of the dentifrice, are preferably distributed uniformly in the dentifrice, usually 0.1 to 10%, preferably 0.5 to 5.%, make up in particular 1 to 3% and especially 1.5 to 2.5% of the dentifrice. The base for the dentifrice usually contains about 5 to 30% water, preferably 10 to 25% and in particular 10 to 20%; about 20 to 70% humectant, preferably polyol humectant, in particular 45 to 65% and especially 50 to 60%; about 0.1 to 5% gel-forming agent, preferably 0.1 to 1% and in particular 0.2 to 0.5%. The humectant preferably consists of a mixture of glycerol and sorbitol, the glycerol content being 5 to 40% of the matrix, for which dentifrice is preferably 20 to 30% and the sorbitol content is 5 to 50%, preferably 25 to 35. The preferred gelling agent is sodium carboxymethyl cellulose and a preferred proportion thereof is about 0.3 to 0.4% Dentifrice is usually present in an amount of 0.5 to 3%. A preferred detergent is sodium lauryl sulfate. The amount of polish in the dentifrice base, excluding the polish in the agglomerates, is normally 10 to 40%, preferably 15 to 30 % and in particular 20 to 25%, including Syloid 244 silicas, which are also used as thickeners.

The various other materials, including the flavorings, which are usually 0.5 to 2.%, colorants, preservatives, sweeteners and dentifrices (fluorides) generally make up no more than 10% of the dentifrice, preferably 2 to 7%. The use of the various ingredients in the amounts indicated and in relation to the agglomerated particles and the medium in which they are distributed results in an attractive product which is stable in storage and in which the agglomerates are distributed uniformly and with an advantageous appearance are.

Once the agglomerates are present, the preparation of the dentifrices containing the agglomerates is relatively simple, but it is important that the mechanical agitation is minimal in order to prevent or delay disintegration, softening and dissolution of the agglomerates in the dentifrice. It is believed that the lipophilic materials and solvents present, such as those in the aromatic oils, slowly dissolve the ethyl cellulose, but not to an objectionable extent if the stirring is not vigorous during processing. If the dentifrice is at an elevated temperature during mixing, possibly due to imposed manufacturing conditions, it is even more important to stir as little as possible. When manufacturing the agglomerated particles using ethyl cellulose as a binder or a combined binder, the manufacturing conditions are less stringent, but care is still required. Suitable devices for distributing the agglomerated particles in the dentifrice can be conventional Baubury or dough mixers running at low speeds or other mixing devices running under mild conditions, provided the mixing is done under controlled conditions to cause substantial breakage, dissolution or disintegration to prevent the agglomerates. When using such mixers, the speed of the mixing blades is usually on the order of 1 to 5 rpm and mixing usually takes 1 to 5 minutes. After the mixing process, the dentifrice can be vented and filled into containers such. B. transparent elastic or compressible tubes. If mixing takes place under vacuum, venting can be omitted.

Although the apparatus and method for making the dentifrices containing agglomerated particles are standard, a recently developed new method is preferred for facilitating the mixing of the agglomerates into the gel dentifrice without undue stirring. This device and the method are explained below. In the attached pictures the

Fig. 1 shows schematically a device for the production of a dental care product containing agglomerated particles from a dental care composition and the previously produced agglomerated particles.

Fig. 2 is an enlarged perspective view of part of the "spotting device" which illustrates the application of the agglomerated particles to a gel stream or a belt.

Fig. 3 schematically shows another device for the production of a dental care product containing agglomerated particles and

FIG. 4 is an enlarged perspective view of part of the “spotting device” of FIG. 3, which illustrates the application of the agglomerated particles to gel streams or belts.

Preferred embodiments of the method according to the invention are described below with reference to FIGS. 1 to 4.

Figure 1 shows a container 111 for the preparation of the gel, which often preferably consists of a Hobart or Dopp mixer, in which the various components of the dental care composition, including the carrier, the gel-forming agent, the polishing agent, the flavoring agent, the colorant, the Detergent, preservative and other adjuvants are mixed together, sometimes under vacuum, to form a matrix to which the agglomerated particles, preferably functional particles, e.g. those are given on the basis of a tooth polishing agent to produce the spotted or speckled toothpaste. A variable speed drive motor and / or controllable speed actuator 113 actuates a positive displacement pump 115 to deliver the gel to an outlet 117, preferably a limited flat opening for squeezing out as a flat band or other suitable stream 119 the agglomerated particles 121 are deposited in the form of separate particles. The pump 115 can be adjusted to control the loading rate of the gel as well as the loading rate of the agglomerated particles so that the ge8

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desired proportion of agglomerated particles can be added continuously to the flowing gel. Preferably, the pump 115 subjects the gel to little or no shear to maintain its consistency (viscosity), and preferably screw pumps with elastomeric walls are used, e.g. those of the Moyno type. The outlet 117 is preferably located in a jacketed vessel or container 123 and is usually arranged so that bands of gel with the agglomerated particles on their surface formed in this container fall out near the center of the container perpendicular to the bottom thereof which can be removed through the central opening 125.

The agglomerated particles to be added to the tooth gel in the prescribed amount are located in a hopper 127 for a feed device 129, preferably a screw, with a speed control device 131 running at a controllable flow rate. The feed device guides the agglomerated particles in the desired controlled amount through an outlet 133 onto a funnel-shaped baffle 135 that directs the exiting stream of agglomerated particles to form a falling stream or curtain upon exit that hits the gel ribbon flowing from outlet 117, the agglomerated particles preferably falling substantially vertically and deposited on the inside of the gel ribbon and be held by him without falling past the gel. Preferably the agglomerated particle curtain covers a substantial part, e.g. 40 to 95%, in particular 60 to 90 b / o of the width of the gel band. It should not be so wide that a substantial proportion of the agglomerated particles miss the belt. On the other hand, it is desirable that this curtain, if possible, be only narrower than the gel ribbon, e.g. from 80 to 90%. Lines 137, 139 and 141 connect to vacuum sources 143 and 145. Although vacuum is desirable to prevent air bubbles from entering the dentifrice, careful processing can prevent such bubbles from entering even without the use of vacuum. After the dentifrice containing the agglomerated particles has fallen through the outlet 125, a pump 147, preferably a screw pump such as a Moyno type, driven by the variable speed motor 149, gently pumps the product into a static mixer 151, preferably of the Kenics type, where it is mixed gently, without disintegration or dissolution of the agglomerated particles. It then passes through line 153 into a collecting container 155, which can be a loading container for a toothpaste filling device, not shown.

FIG. 2 shows a gel loading device 157 with a delivery tube 159 and a nozzle 117, the nozzle having a flat rectangular opening 161. The gel loading device and the opening in the nozzle can be set differently. The loading direction can be changed as desired, as can the delivery angle, but the loading direction should have a horizontal component. It is usually 0 to 45 °, e.g. 10 to 30 ° to the horizontal. The rectangular opening can also be changed in size so that it is more limited. However, care must be taken that the gel ribbon is connected and that it is not diluted beyond the gel strength. Usually it is 1 mm to 1 cm, e.g. 2 to 6 mm thick. The gel stream or ribbon is oriented so that the stream or curtain of agglomerated particles can fall exactly on the ribbon, preferably when the agglomerated particles fall substantially vertically and the gel moves in a horizontal component direction so that the gel moves moved among the falling agglomerated particles that come into contact with it and stick to it. The gel ribbon 163 is shown falling down and to the right, while agglomerated particles 165 from the outlet 167 of the guide device 135 (FIG. 2) fall onto this ribbon.

FIG. 3 shows the container 211 for the production of a gel, which can be the same as in FIG. 1 and works in a similar manner. The valves 213 and 215 in line 217, together with the positive displacement pump 219, allow the gel to be returned through the mixer if desired. Lines 220 and 221 and valves 222 and 223 allow the delivery of tooth gel or tooth paste for the manufacture of a dentifrice that does not contain agglomerated particles. If the mixing device 211 contains tooth gel, the line 225 and the valve 227, when open, with the valves 215, 222 and 223 closed and the valve 213 open and the gel pump 219 in operation, enable the gel to be delivered to the gel feeder 229 and through it at a controlled rate Line 231 to a similar but opposite gel loading device 233. Both devices have relatively limited shallow openings and nozzles, which are better illustrated in Figure 4. They also advantageously have additional support devices for the gel as it exits the nozzles to maintain its band shape and guide its flow. The pump 219 can be set to control the gel loading rate so that when controlling the loading rate of the agglomerated particles, the desired proportion of these particles can be added continuously to the flowing gel. Preferably, pump 219 is the same as pump 115 previously described. The gel feeders or extruders

229 and 233 and line 231 are preferably in a jacketed kettle or container 235 and are usually centrally located so that layers of gel with agglomerated particles inside them formed in such a kettle are perpendicular or near the center of the kettle fall substantially perpendicular to the bottom thereof, from which they are removed through an outlet which is connected to the line 237. The non-numbered outlet is at the bottom of the kettle, and it is preferred that the gel feeder 233 terminate near the outlet to avoid crimping of the two-layer tape containing the agglomerated particles, resulting in the inclusion of Air can lead if no vacuum is applied. It is also preferred that the shape of the outlet conforms to and is oriented towards the shape of the band (usually flat rectangular) in order to keep congestion in the removal of the dentifrice from the jacketed kettle to a minimum, and thus delays, including To reduce air and the solution of the binder for the agglomerated particles as much as possible.

The agglomerated particles to be added to the tooth gel in a predetermined amount are in the funnel

230 a controlled flow rate feed device 232, preferably of the screw type, with a speed control device and a drive combination 234 which guides the agglomerated particles at the desired controlled speed to an outlet of the tube 236 on a manifold 238 which spreads them so that they spread the manifold in the form of a falling stream or thin curtain leaving in

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Size and orientation correspond to the bands generated by nozzles 229 and 233. Instead of the screw conveyor, other screw, belt and vibration type conveyors can be used. Line 228 is connected to a vacuum source which, like vacuum line 259, may or may not operate.

The valves 239 and 241 are arranged so that the product can either fall through the line 243 or there is a connection to the pump 245, which is preferably of the Moyno type. The screw pump 245, driven by motor 247, gently pumps the product through line 249 to static mixer 251, preferably of the Kenics type, where it is gently mixed evenly without disintegration or dissolution of the agglomerated particles contained therein. The line 253 then passes to the collecting container 255, which can be a feed tank for a toothpaste filling device, not shown.

Although the apparatus and method described can be operated without the use of vacuum, such is often desirable to prevent air from entering dental care materials. It can then be worked completely or partially under vacuum. Preferably, the loading devices for the agglomerated particles and the device for applying the agglomerated particles are under vacuum. Accordingly, the vacuum lines or branches 259 and 228 are shown in the drawing.

In Figure 4, gel loading devices 229 and 233 have nozzle parts 275 and 277 with limited flat openings 263 and 265 which, as shown, are connected to adjustable support guides 267 and 269 and facilitate proper alignment of the railings or webs so that the curtain from agglomerated particles can fall on them exactly. The gel band on the guide 267 is designated 271 and is shown without agglomerated particles deposited thereon. A similar band 272 on the guide 269 is located under the derivative of the first guide and near the outlet from the boiler. Preferably, the agglomerated particle curtain falls vertically or substantially perpendicularly on the gel ribbon 271 after the ribbon has left the guide 267, but still in one direction with a horizontal component, e.g. moved at 60 ° from the horizontal. If you pay attention, however, some agglomerated particles can be deposited on the gel 271 while it is still in contact with the support. When the gel ribbon 271 with the adhering agglomerated particles falls vertically or substantially vertically, it comes into contact with the ribbon 272 and the two ribbons enclose the agglomerated particles between them. In order to avoid ruffling which can cause air entrapment, the guide 269 may preferably extend either in a straight line or as a convex curve up to close, usually 5 to 25 cm to the outlet opening from the kettle, and the gel ribbon passes the oriented and similarly shaped ones Outlet without crimp, keeping the execution speed at the same value as the sum of the addition speeds.

The feed rates (and thicknesses) of the handrails can be about the same, or they can usually be varied in the range 1: 4 to 4: 1 to each other. The controlled and proportionate loading of agglomerated particles emerges from the discharge pipe 236 into the distributor 238, which is shown in expanded form with the side walls 279 and 281, the bottom 283 and the dividing spikes 285 and is arranged in a “Pascal's triangle” form. The feeding devices for the agglomerated particles and the like

Gel and the openings in the nozzles of the gel loading device are adjustable as indicated in relation to FIG. 2. The first or upper gel stream or band of gel is oriented so that the stream or curtain of agglomerated particles, usually 0.5 to 5 mm thick, falls exactly on the gel band, preferably when the agglomerated particles fall substantially vertically and the gel is in one Direction with the horizontal component moving so that the gel passes under the falling agglomerated particles that come into contact with and adhere to it. Gel ribbon 271 is shown falling downward to the right as agglomerated particles 273 fall from manifold 238 through baffle 235 (Figure 4), and ribbon 272 falls to the left under ribbon 271.

The described devices of FIGS. 1 to 4 and the corresponding preferred methods enable the production of speckled dentifrices in an efficient and rapid manner without the need for conventional shear mixing devices. The agglomerated particles do not clump together, they do not disintegrate and, because the process is quick, the product can be quickly manufactured and filled into tubes before the binder becomes noticeably softened or dissolved. This gives the preferred clear gel-like dentifrice, usually with attractively distributed, individually visible, separate functional agglomerated particles without clouding due to the breaking up of the agglomerates and a distribution of the finely divided functional material, such as the polishing agent, in the dentifrice.

Other advantages of the invention include immobilization of the agglomerated particles with respect to the gel band and the resulting lower dissolution of any binder in a solvent material that may be present in the gel. Feeding the gel in a sheet that becomes vertical over a container outlet after the agglomerated particles have been deposited reduces the dwell time in the device prior to removal and hence the release of the binder for the agglomerated particles, thereby preventing the agglomerated particles from disintegrating . The sandwich effect, which is illustrated in FIGS. 3 and 4, leads to an even better distribution of the agglomerated particles in the dentifrice composition and is particularly good for compositions to which the agglomerated particles do not adhere firmly.

The invention thus includes the production of a dentifrice which contains dispersed agglomerated particles therein.

This method is characterized in that at least one stream is made from a gel or paste dental composition containing water, a humectant, a detergent, polishing agent, flavoring agents and a gel-forming agent which makes the surface of the composition sticky for the agglomerated particles, whereby the dental composition makes up the major part of the dentifrice, produces a stream of agglomerated particles to be distributed in the dentifrice, directs this onto the surface of the stream of the dental composition and controls the relative feed rates and proportions of the streams of dental composition and agglomerated particles to be dispersed in the dentifrice, so that when the stream of agglomerated particles comes into contact with the stream of dental composition, the agglomerated particles are not sufficient to cover the surface of the dental composition, the agglomerated Adhesive particles attached to the stream of the dental composition and a dentifrice is obtained, which contains the agglomerated particles in the desired amount.

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An apparatus for carrying out this method comprises means for generating a moving or flowing stream of dental composition, which usually consists of a dentifrice without the agglomerated particles to be distributed therein, and is of such a nature that the agglomerated particles adhere to it. In such a device, a stream or a band of dental gel can be generated by pressing the latter through a suitable opening so that it emerges from this opening in the desired form, preferably as a flat band. The stream or curtain of agglomerated particles with preferred particle sizes corresponding to a mesh size of 2.00 to 0.177 mm is usually directed onto the gel band in such a way that these are distributed evenly over the inner part of the surface of the flowing band and adhere to it, whereupon the gel ribbon with adhering agglomerated particles can be received in a container from which it is preferably removed continuously when more gel containing agglomerated particles enters or is generated therein. According to a preferred embodiment, the agglomerated particles are brought between two bands of dentifrice (sandwiching) and the agglomerated particles are brought into the form of a uniform falling curtain by means of a Pascal triangular arrangement of barriers.

The following examples illustrate the invention. In the description, the examples and in the patent claims, all parts are parts by weight, unless stated otherwise.

example 1

5 parts of powdery ethyl cellulose (10 10_3Pas) with the physical properties specified above were dissolved in 5 parts of 95% ethanol and in a Hobart mixer with 95 parts of calcined aluminum oxide (Microgrit WCA 9F) with particle sizes of 0.5 to 10 μm and one average particle size of 3 to 5 microns mixed. Mixing was carried out for about 4 minutes until the mixture was uniform, whereupon it was pressed through a sieve with a mesh size of 2.00 mm and the pressed material was dried in an oven at 65 ° C. for 1 hour. The dried agglomerates were then sieved through a sieve with a mesh size of 0.595 mm and the cut remaining on a sieve with a mesh size of 0.25 mm was collected. The dried agglomerates contained the calcined alumina and ethyl cellulose. The agglomerates obtained in this way have an angular shape, the ratio of maximum length to maximum width usually being in the range from 1 to 2 and for most particles in the range from 1.1 to 1.5. The angular appearance of the particles can be a factor that makes dental care products so attractive in appearance, at least for some consumers.

A base for a clear or translucent dentifrice that contains all components except the agglomerates is made from the following ingredients:

Ingredients parts by weight

Glycerin, 99.3% pure 25.00 sodium carboxymethyl cellulose 0.35

Sorbitol, 70% aqueous solution 36.04 polyethylene glycol 600 3.00 water 3.00 sodium saccharin 0.25 sodium benzoate blue dye, FD&C blue 0.50

No. 1.1% aqueous solution 0.20 sodium monofluorophosphate,

1 to 60 (on 0.76

Silicon dioxide, Zeo 49 18.00 5 Synthetic silicon dioxide,

Syloid 244 5.50

Sodium lauryl sulfate 1.20 flavorings (spearmint oil,

Peppermint, wintergreen, clove oil,

io etc. as desired) 1.20

95.00

5 parts of the described agglomerates with particle sizes of -0.595 mm + 0.25 mm were mixed in a mixer running at an i5 speed of about 2 rpm with 95 parts of the described basic composition for the dentifrice, whereupon the mixture was deaerated and automatically capped sealed compressible tubes were filled, which were then sealed. 20 During mixing, deaeration and filling, the agglomerates, which are essentially evenly distributed in the dentifrice, remain separate and undissolved in the base material, so that when the tube is opened after it has been filled, and preferably after about 25 months Storage when squeezing out the toothpaste the agglomerates appear in their original intact form, which contrasts with the bluish gel. If the product is evaluated immediately after filling without storage, the agglomerates can be felt. However, after 30 weeks of storage before use for 2 weeks to 1 year or more, they are sufficiently softened due to the dissolving of the ethyl cellulose by the aromatic oil, sometimes with the help of dentifrice or other surfactants that may be present and 35 other components, so that they appear as separate and not "smeared" particles, but are satisfactorily imperceptible. During tooth brushing, the agglomerated particles are slightly reduced in size, they do not irritate the gums and are easily removable from the oral cavity after the tooth brushing is finished.

Although the presence of the anionic detergent in the base may be helpful, it is believed that the controlling component of this base is the 1.2% flavor. In order to achieve the best dispersions of the agglomerates, 0.5 to 2% and preferably 0.8 to 1.5% of such a substance or a mixture thereof, of which at least half are normally effective as solvents for the ethyl cellulose, are desired . The flavor usually contains more than 50% so and often more than 80% solubilizing hydrocarbons, esters, alcohols and aldehydes.

In the manufacture of the dentifrices according to the invention, in which the agglomerates are dispersed in a gel matrix, care must be taken when mixing that the agglomerates do not disintegrate. Whenever there is any indication of this, mixing should be interrupted and, provided that the appearance of the dentifrice is not significantly affected, usually by an unacceptable cloudiness, should be filled into tubes immediately. 60 Instead of the mixing process described above, it is often advantageous to use another processing technique as described above, in which a uniform "jet" of the agglomerates is deposited by gravity on a continuously falling extended band of gel on which the agglomerates adhere, so that an even distribution of the agglomerates in the dentifrice is achieved. When the dentifrice according to the invention containing agglomerates compresses into a

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When the aluminum tube is filled, the agglomerates in the dentifrice are not visible until they are squeezed out of the tube, but are then present in the toothpaste in the form of separate particles, which give it an attractive appearance. However, if instead of normal aluminum tubes elastic transparent tubes, e.g. B. tubes made of polyvinyl chloride or another suitable polymer can be used to see the agglomerates through the tube and through the transparent gel and observe their movement when squeezing the toothpaste. This creates another aesthetic effect and makes tooth brushing more interesting, especially for children. In addition, the functional agglomerates alert the person using such a dentifrice to the presence of the polishing agent or other functional ingredients in the dentifrice and remind them of the importance of brushing their teeth for these components to be effective.

The above formulation is for a gel dentifrice in which the normally used 41.04% sorbitol solution has been reduced to 36.04% to allow the introduction of the 5% agglomerates. Due to this change, the percentages of the other components of the dentifrice may remain the same as in a product without agglomerated particles, with the exception of the main component, i.e. the sorbitol solution. If the content of the agglomerates for such dentifrices is varied, the formulation can be modified in the same way. However, it is also possible to start from the initial gel formulation, i.e. of 41.04% sorbitol solution and the other components accordingly, so that the desired percentage of agglomerates can be introduced.

In the above formulation, 1% ultramarine blue pigment can be used instead of 1% of the microgrit, so that the agglomerated particles acquire a certain blue color. Instead of the stated amount of ultramarine blue, 0.5 to 2.0% of the pigment or mixtures of pigment (s) and polishing agent (s) can be used in a ratio of 1:10 to 10: 1. Alternatively, about 0.1 to 1% of any suitable water-insoluble (or oil-soluble) dye can be used. In such cases, the dye solution may or may not be included in the dentifrice base formulation, provided sufficient contrast is achieved between the agglomerates and the base.

Of course, the various components of the formulation can be replaced by others, e.g. B. those described above, whereby useful products are also obtained. E.g. the various pigments and dyes mentioned can be used, the sodium lauryl sulfate can be replaced by the sodium salt of ethoxylated higher fatty alcohol sulfates or the sodium salt of hydrogenated coconut fatty acid monoglyceride monosulfates, and dicalcium phosphate dihydrate and / or dicalcium phosphate mixtures (anhydrous) can be used instead of the polishing agents will. The proportions of the various components can be varied by + 10% + 20% and + 30% as long as they remain within the specified ranges, whereby satisfactory products with similar properties are obtained, although the proportions specified in this example are preferred.

Example 2

75 parts of anhydrous dicalcium phosphate and 15 parts of dicalcium phosphate dihydrate, both with an average smallest particle size of about 4 p.m., were mixed with 10 parts of ethyl cellulose and 10 parts of ethyl alcohol in one

Hobart mixer mixed. Alternatively and preferably, ethanol and ethyl cellulose can be premixed and then mixed with a premix of the dicalcium phosphates. The mass formed is pressed through a sieve with a mesh size of 2.00 mm and then dried in an oven at 65 ° C for 1 hour. The dried agglomerates are sieved through a sieve with uniform openings of 0.42 mm, whereupon the agglomerates which do not pass a sieve with a clear mesh size of 0.177 mm are collected. The agglomerated functional particles are then mixed with a dentifrice base mass of the formulation according to Example 1, with the difference that the polish in this base mass is replaced by sodium aluminosilicate, as sold under the trade name Zeolite 4A. The percentage of agglomerated particles in the final product was 2% with the amount of sorbitol solution increased by 3%.

This formulation can be varied by adding the polishing agent in the agglomerated particles by hydrated alumina with an average particle size of less than about 10 µm calcium carbonate, the particles of which are all substantially less than about 7.4 µm, or insoluble sodium metaphosphate with a average particle size of about 5 (xm replaced, all of these particle sizes being final particle sizes.

The dentifrices of this example are transparent or translucent products containing agglomerated particles that have an aesthetically pleasing appearance. The visible particles of the agglomerated polishing agent, which can be replaced in whole or in part by other functional insoluble materials, are essentially uniformly dispersed as visible separate particles in the base of the dentifrice and are essentially imperceptible after three months of use.

Example 3

Instead of dissolving diethyl cellulose in ethanol or another suitable solvent, agglomerates are made by mixing the polishing agent and the ethyl cellulose, sometimes in the presence of a reduced amount of ethanol to form a powder mixture. This mixture is compressed in a rotary tablet press into pieces with a thickness of approximately 6 mm and a diameter of 25 mm. These pieces are then granulated in an oscillating granulator into smaller particles, preferably those that pass through a sieve with a clear mesh size of 0.595 mm and remain on a sieve with a clear mesh size of 0.25 or 0.177 mm. This way of producing the agglomerated particles can also be applied to the formulations for agglomerates given by the preceding examples. Although the binding effect of ethyl cellulose cannot be so great, the products of this example for incorporation in dentifrice are also satisfactory with an aesthetic appearance and functional effects. If the binding effect of the ethyl cellulose in the above formulation is not sufficient, its proportion can be increased, sometimes up to 100 or 200%, but such an increase is associated with additional costs and therefore the "wet process", in which solutions of the ethyl cellulose in ethanol or other suitable solvent, often preferred.

Example 4

95 parts of calcined aluminum oxide (Microgrit WCA 9F) with particle sizes in the range from 0.5 to 10 (xm and

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an average particle size in the range of 3 to 5 µm are mixed with three parts of powdery polyvinylpyrrolidone from GAF Corporation, trade designation K-39-32. 2 parts of the ethyl cellulose powder used in Example 1 are dissolved in 5 parts of ethanol (95%) and the PVP-aluminum oxide mixture is mixed with the solution in a Hobart mixer. Mixing takes about 4 minutes until the mixture is uniform, whereupon it is pressed through a sieve with a mesh size of 2.00 mm and the material pressed through is dried in an oven as in Example 1. The dried agglomerates are then screened and collected, also as in Example 1. The agglomerates so obtained have an angular shape, usually with a ratio of maximum length to maximum width as that in Example 1. As in Example 1 ', becomes transparent or translucent Base mass for a dentifrice prepared, which contains all components except the agglomerates, but instead of the 36.04 parts of sorbitol solution 39.0 parts of sorbitol solution is used.

2 parts of the described agglomerates with particle sizes of -0.5 mm +0.25 mm are gently mixed with 98 parts of the specified dentifrice base mass in a mixer running slowly at about 2 rpm, whereupon the mixture is deaerated and automatically filled into compressible tubes closed with caps which will then be locked. The procedure used was as in Example 1. If the product is evaluated without storage immediately after filling, the agglomerates are palpable. After storage for 2 weeks to 1 year or more, they are due to the dissolution of the PVP by the moisture present and the dissolution of the ethyl cellulose by the aroma oil, both of which appear to sometimes be supported by the dentifrice or other surfactants that may be present , and sometimes softened sufficiently by other components that they are imperceptible.

If the amount of flavoring in the gel matrix is 0.6%, i.e. is reduced by half of the above formulation, the PVP-ethyl cellulose binder system is still effective for the agglomerated particles and these particles are satisfactorily imperceptible after storage. The binder system is also effective when the amount of flavor is varied and is 0.3%, 0.9% and 1.5%, respectively. However, the larger proportions of flavoring agent (and / or other lipophilic solvents)

cause solubilization somewhat earlier than desired. In these cases the proportion of PVP and ethyl cellulose is preferably varied, e.g. B. on 2 parts of PVP and 3 parts of ethyl cellulose. Similarly, if the tactility of the agglomerated particles is greater than desired, they can be increased by increasing the level of PVP, e.g. softened to twice the ethyl cellulose. The amount of agglomerated particles and their size can be changed within the specified ranges. Other of the above materials can be used in place of the alumina polishing agent, including other types of water-insoluble functional substances. The variations in formulations and processes described in Example 1 are also applicable to this example and result in useful agglomerates and dentifrices containing these agglomerates.

Example 5

75 parts of anhydrous dicalcium phosphate and 15 parts of dicalcium phosphate dihydrate, both with an average smallest particle size of about 4 (in, are mixed with 5 parts of ethyl cellulose, 5 parts of PVP and 10 parts of ethyl alcohol

get mixed in a Hobart mixer. Alternatively and preferably, the ethanol and ethyl cellulose can be premixed and then mixed with a premix of the dicalcium phosphates with PVP. The mass formed is pressed through a sieve with a mesh size of 2.00 mm and then dried in an oven at 60 ° C for 1 hour. The dried agglomerates are then sieved through a sieve with a clear mesh size of 0.42 mm, the agglomerates which do not pass through a sieve with a clear mesh size of 0.177 mm being collected. The agglomerated functional particles are then mixed with a dentifrice base material of the formulation given in Example 4, with the difference that the polishing agent in this base material was replaced by sodium aluminosilicate, trade name Zeolite 4A.

The dental care products obtained in this way and containing agglomerates are transparent or translucent and have an aesthetically pleasing appearance. If the formulations and the process conditions are varied as in Example 2, good products with the desired properties are also obtained.

Example 6

The functional polish of Example 5 is replaced by a mixture of 10 parts of anhydrous dicalcium phosphate and 90 parts of calcium carbonate, the total amount of the polish being the same and the same procedures being followed. The product obtained is equally satisfactory in terms of functional effects and aesthetic appearance. Similar results are obtained if other mixtures of the polishing agents are used for the agglomerates and their proportions are varied.

Example 7

Instead of dissolving the ethyl cellulose and the PVP in ethanol or another suitable solvent, agglomerates are combined as in Example 6 by mixing the polishing agent, PVP and ethyl cellulose, sometimes with a reduced amount of ethanol, to form a powder mixture. This mixture is compressed in a rotary tablet press into pieces with a thickness of approximately 6 mm and a diameter of 25 mm. The pieces are then granulated in an oscillating granulator into smaller particles, preferably those which pass through a sieve with a clear mesh size of 0.42 mm and remain on a sieve with a clear mesh size of 0.25 or 0.177 mm. Although the binding effect of the PVP and the ethyl cellulose cannot be so great, the products of this example are satisfactorily suitable for incorporation into dentifrices and give them an aesthetic appearance and functional effects. If the binding effect of the PVP and the ethyl cellulose in the above formulations is insufficient, their proportions can be increased, sometimes up to 100 or 200%, but such an increase causes additional costs, so that the "wet process" in the solutions of PVP and ethyl cellulose are often used.

Preparation 1

In the above examples, the polyvinyl pyrrolidone, i.e. the water-soluble binder portion of the combined binder is partially (50%) or completely replaced by the following water-soluble binders: gum arabic cum, gelatin, corn starch, sodium carboxymethyl cellulose, sodium alginate, polyvinyl alcohol, carrageenan, xanthan gum

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gum and tragacanth. The agglomerates so produced, when incorporated into gel dentifrices such as those described in the previous examples, retain their individuality and integrity during processing, but become imperceptible when stored in dentifrices, while maintaining their original shape, as do the agglomerates which were made with PVP ethyl cellulose binders. However, the PVP-ethyl cellulose binders are generally superior in their combination of desirable properties, including processing stability, compatibility with the other components of the dentifrice and the change from tactility to non-tactility without loss of integrity of the agglomerates and substantial change in their appearance.

Preparation 2

Agglomerates of different compositions were compared with those based on ethyl cellulose and PVP. The agglomerates were generally made by the wet process of Example 4. The formulation for the agglomerates contained 95% calcined alumina, 2% ethyl cellulose and 3% PVP, these materials being the same as in Example 4. The agglomerates of the comparative tests were also made by the wet process, with the exception of one which was dry. ken or “piece” method of Example 7 was produced.

The agglomerates were examined in the following manner: 100 mg of each type were weighed out, placed separately on glass slides, then 4 drops of water were added to each and each slide was covered with a different slide and then the time until the physical change and the type of physical change in the Grain was noted. If 2% sodium carboxymethylcellulose was used as the binder, the agglomerates lost their integrity within 15 seconds, which is also the case if 2% hydroxypropylmethylcellulose was used as the binder for the agglomerates, but this then took 2 minutes. Agglomerates made with a binder made from 2% methyl cellulose and 3% PVP soften, swell and lose their integrity after about 2 minutes. If 5% PVP was used as the only binder, the agglomerates softened after 8 minutes. If the binder consisted of 1% methyl cellulose (400 cP) the agglomerates lost their integrity after a little more than 5 minutes and if the binder consisted of 10% polyethylene glycol 6000 and 1% magnesium stearate, the agglomerates being made by the dry process , they lost their integrity after 19 minutes. The «control» agglomerates with 2% ethyl cellulose and 3% PVP were still intact in the same test after more than 6 hours.

Example 8

Using the formulation and the method according to Example 1, a clear gel dentifrice containing agglomerated particles was produced with the device of FIGS. 1 and 2. The various gel-like (or pasty) components were mixed together in mixer 111 and preferably pumped to the extruder with a Moyno pump, which, as indicated, has a flat slot-shaped nozzle at its end with a relatively narrow rectangular opening. Preferably this nozzle is at an angle of about 10 to 45 ° from the horizontal, e.g. 30 ° downwards.

The feed rate of the device that supplies the agglomerated particles, an Acrisan screw conveyor, is adjusted to match the speed of the gel delivery. If e.g. if a dentifrice containing 3% agglomerated particles is desired and the loading rate for the gel is 3 kg per minute, the agglomerated particles are fed at a rate of 93 g per minute. Conventional electronic or mechanical devices are used to maintain the desired ratio of feed rates or to adjust when changes in these ratios are desired to produce various products.

In the drawing, the agglomerated particle loading mechanism is shown only schematically in Figure 1 and Figure 2 shows only the end thereof, however, are different types of conveyors, including screw, belt, weigh belt, electronically controlled gravimetric conveyors and others usable and the delivery schedule can be changed. The delivery takes place in such a way that, if at all, few agglomerated particles fall past the gel and the gel stream holds the impacting agglomerated particles. The agglomerated particles fall separately and the gel moves beneath them quickly enough, usually at a rate of 10 to 100 cm / sec, e.g. 20 to 50 cm / sec. That individual agglomerated particles hit the gel and adhere to it, with very few hitting and bouncing off other particles already held. Furthermore, all or almost all of these rebounding particles subsequently adhere to the dental composition.

The falling gel to which the agglomerated particles adhere does not remain long in the container in or over which the agglomerated particle releasing device is located, since it falls through the center of this container and most of it exits almost immediately to the outlet. This short residence time in the "spotty bowl" is very desirable and helps to maintain the integrity of the agglomerated particles in the dentifrice. The dwell times in the container can vary. Typical dwell times are 20 seconds to 2 minutes, the shorter the better. The rapid throughput, the lack of mobile agglomerated particles and the central gel discharge from the kettle also help to avoid agglomeration of the agglomerated particles in clumps that are objectionable. The additional volume of the container is provided to hold gel which is supplied in a period during which the discharge device is temporarily stopped before the feed to the container can be stopped. For example, the container can often contain only a small amount of the agglomerated particle gel, e.g. 10 to 25% of its volume. Alternatively, the other material can act as a "wall" which delimits the gel with the agglomerated particles within the container.

After leaving the container, the gel is gently pumped through a static mixer using a Moyno pump to ensure complete mixing. The preferred static mixer, a Kenics mixer, is described in Chemical Engineering under Handling Viscous Materials - Motionless Mixer for Viscous Polymers, March 19, 1973. Although it is desirable to use a mixer or a suitable container in front of such a device prior to discharging the gel to a filling device, the method and device described herein can often achieve sufficient distribution of the agglomerated particles in the gel without such a mixer , so that in some cases no mixer is used.

The process conditions are not considered critical, but the vacuum applied is usually in the range of about 300 to 700 mm Hg, e.g. B. from 400 to 600

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mm Hg. Temperatures can be about room temperature or higher, e.g. B. in the range of 10 to 40 ° C. The pressure for squeezing the gel varies with the gel viscosity, but a pressure of 0.03 to 0.7 kg / cm2 is considered appropriate.

The various parts of the device described, since they are used to manufacture a product that enters the oral cavity, should be made of a non-corrosive, safe material. Stainless steels have been found to be preferred, and the mixers, extruders, pumps, and valves, as well as other parts that come into contact with the liquid or gel materials, are preferably made of the stainless steel normally used in the food processing industry.

When a dentifrice containing 2% agglomerated particles with silica, sorbitol, glycerin, car-boxymethyl cellulose, sodium lauryl sulfate, flavor and water in the gel and alumina and ethyl cellulose in the agglomerated particles like that of Example 1 is prepared using the device described, is obtained a desired product in which the agglomerated particles are evenly distributed in the clear gel,

without a cloudiness or disintegrated agglomerates being noticed. Similar results are obtained when other dentifrices containing agglomerated particles, such as those according to the prior art and those of Examples 2 to 9, are produced using the method and the device according to the invention.

When the method according to the invention is carried out in practice, it is preferred that the dental gel or the paste is in flat band form, but variations of this form are also possible, e.g. arcuate bands and even cylindrical or tubular streams.

It is also preferred that the stream or curtain of agglomerated particles consists of a suitably thin straight curtain of this material, e.g. with a thickness of 0.1 mm to 1 cm, such as 0.5 to 5 mm, which falls due to gravity, but the agglomerated particles can also be directed violently against a dentifrice. E.g. In some cases, agglomerated particles can be directed horizontally against a vertically moving stream of dentifrice, collecting the non-adherent particles for recycling. In addition, the stream of dentifrice can be given a rotating movement, so that its entire exposed surface "picks" agglomerated particles that are directed at it on one side. Transported agglomerated particles can impact a gel stream and be immobile and separated on it. While such variations are applicable as well, the method described herein is considered superior.

The proportion of agglomerated particles fed to the belt or web of gel dental care products is small compared to the total dental care products containing the agglomerated particles and the gel supplied. The loading rate for the agglomerated particles is usually adjusted so that the amount of agglomerated particles directed at the gel is not sufficient to cover it, and preferably it is not sufficient to cover more than half of the part of the gel that does Curtain of agglomerated particles is exposed. Although, as previously mentioned, various ways can be used to get the agglomerated particles to adhere to the gel tape, it is preferred that the agglomerated particles be perpendicular in the form of a pre657 775

hang on the gel ribbon, which moves with a horizontal component. The movement can be horizontal or have a substantial horizontal component, whereupon the gel falls after the agglomerated particles have been taken up, but a slope from the horizontal of e.g. 10 to 60 ° preferred for vertically falling agglomerated particles after they have left a dispenser. The viscosity of the gel is not critical as long as the agglomerated particles adhere sufficiently to it, nor is the size of the particles critical, but they usually correspond to a mesh size of 2.00 to 0.177 mm, preferably 0.595 to 0.177 mm and in particular from 0.595 to 0.250 mm. The agglomerated particles preferably have sharp edges and are partially embedded in the gel stream when falling onto them, so that they become immobile immediately, but similarly good results can also be obtained with rounded agglomerates. Although the agglomerated particles are preferably visible in a clear gel, which makes the product more aesthetically attractive, they can have a refractive index that makes them invisible. The term “agglomerated particles” thus encompasses both visible and invisible separate particles of different materials, agglomerates of finely divided polishing agents being preferred. Furthermore, although it is preferred that the agglomerates consist of finely divided polishing agent and binder, they can also contain other “active” components, such as therapeutic substances, coloring substances, flavorings and fluorides.

The dentifrice mass on which the agglomerated particles are deposited can consist of the entire dentifrice with the exception of the agglomerated particles, but this is not necessary. It is possible to add some components of the dentifrice after adding the agglomerated particles. E.g. it may be desirable to mix in the flavor, which may contain some volatile components, before the Kenics mixer, but after the agglomerated particles have been deposited while vacuum is applied to the product. Such a process has the advantage that the flavor is retained and losses of more volatile components due to the use of vacuum during the "stippling" are prevented. Furthermore, the flavor components that render the binder of the agglomerated particles soluble have less contact time with the agglomerated particles. The Kenics or another static mixer that runs with a relatively low shear effect, however, mixes the flavoring material sufficiently evenly into the dentifrice. Similarly, other components, usually smaller amounts of adjuvants, can be added to the dentifrice after incorporation of the agglomerated particles.

The encased container into which the dentifrice containing agglomerated particles falls can be under vacuum or open to the atmosphere. Instead of being enclosed in a container, the “spotting device” can have a collecting container underneath it. However, it is preferred that the device be covered and under vacuum if the inclusion of air would otherwise be a problem. So there is a container for the "spotting device" and a container for the collection of the product formed. The method and the device according to the invention are suitable for the production of a large number of different dental care formulations which contain different proportions of agglomerated particles. Varying the amount of agglomerated particles is a simple matter because only the rate of delivery of the

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agglomerated particles changed and the gel loading speed must be adjusted accordingly.

The various advantages achieved according to the invention are: a more efficient procedure, fewer mixers with moving parts and the stabilization of the tooth gel or tooth paste. It is known that various dentifrices are liquefied by excessive mechanical processing. The mixing method according to the invention for adding the agglomerated particles to the dentifrice avoids such processing and enables the desired viscosity of the tooth gel to be maintained.

Example 9

A method for producing a dental care agent containing agglomerated particles is carried out as in Example 8, but the device according to FIGS. 3 and 4 is used. Accordingly, two gel railings are produced, each with half of the total formulation, with the exception of the agglomerates. The flat slot-shaped nozzles are inclined downwards from the horizontal at an angle of approximately 30 °. The gel speed is about 20 to 50 cm / sec. and the gel is preferably sticky enough that under appropriately controlled conditions most agglomerates striking the first gel stream will adhere to it, with the remainder or substantially all of the remainder being positioned by the other gel stream.

The device for supplying the agglomerates is shown in FIG. It consists of a Pascali triangle arrangement with thorns. It is inclined downwards at an angle of about 30 ° from the horizontal and its width makes up about 90% of the gel flows at the end of the delivery. Although the Pascali triangle arrangement is preferred, other loading devices can also be used.

The dentifrice formed has all the advantages of the dentifrice according to example 8. The method and the device of this example are particularly suitable for keeping agglomerates in order and in a uniform distribution on a gel dentifrice if it is not strongly adhesive. This prevents the agglomerates from rebounding, spares losses of agglomerates and it is not necessary to return or discard non-adherent agglomerates. Even with non-adhesive gels and / or non-adherent gels and / or non-adherent agglomerates, the production of the end product can be controlled in such a way that it contains a uniform, desired content of agglomerates, since losses of agglomerates are kept to a minimum.

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Claims (10)

657 775 PATENT CLAIMS 1. A process for the preparation of a dentifrice which has functional, agglomerated particles which contain a water-insoluble powdery functional material and water-insoluble, ethanol-soluble ethyl cellulose, characterized in that at least one stream is produced from a gel-like or pasty dental composition, the water , contains a humectant, a cleaning agent, polishing agent, flavoring agents and a gelling agent which makes the surface of the composition for the agglomerated particles sticky, the dental composition making up the major part of the dentifrice, producing a stream of agglomerated particles to be distributed in the dentifrice, this is directed to the surface of the stream of the dental composition and controls the relative feed rates and proportions of the streams of dental composition and agglomerated particles to be dispersed in the dentifrice, so that if the stream of agglomerated particles comes into contact with the stream of dental composition, the agglomerated particles are not sufficient to cover the surface of the dental composition, the agglomerated particles adhere to the stream of the dental composition and a dentifrice is obtained which distributes the agglomerated particles into contains the desired amount. 2. The method according to claim 1, characterized in that one uses so many agglomerated particles that they make up 0.1 to 10 wt .-% in the finished dentifrice. 3. The method according to claim 1, characterized in that the stream consists of a gel band and contains all components of the dentifrice with the exception of the agglomerated particles to be distributed in the dentifrice, the gel band is produced by pressing through a suitably shaped opening and in a direction with horizontal Component flows, the stream of agglomerated particles has particle sizes that correspond to a mesh size of 2.00 mm to 0.177 mm, the agglomerated particles are in the form of a falling curtain, which is oriented so that it points downwards in a manner onto the gel ribbon falls that the agglomerated particles are evenly distributed over and held by a substantial part of the width of the flowing gel ribbon, but the particles are not sufficient to cover more than half of the surface of the ribbon that is exposed to the falling particles, the gel ribbon with the adherent agglomerate particles are collected in a container under vacuum and continuously removed therefrom when further gel containing agglomerated particles enters the container. 4. The method according to claim 1, characterized in that one produces a plurality of band-shaped streams from a gel-shaped or pasty dental composition, which makes up the greater proportion of the dentifrice, a stream of agglomerated particles to be distributed in the dentifrice, this stream of agglomerated particles aligns the surface of at least one of the streams of gel or paste dental composition and controls the relative feed rates and proportions of the gel or paste dental composition and the agglomerated particles to be dispersed therein, so that when the stream of agglomerated particles falling in the form of a curtain coincides with the stream comes into contact from a gel-like or pasty composition, the agglomerated particles adhering to the gel tape or paste tape are not sufficient to cover the surface of the tape, and at least two of the plurality of streams de r brings together the dental composition with its larger surfaces to trap the agglomerated particles between them. 5. The method according to claim 4, characterized in that the streams of gel-like or pasty dental composition consist of a pair of Geländer which flow continuously in partially opposite directions with horizontal components, and aligns the stream of agglomerated particles so that it downwards one of the flowing railings falls and the amount of agglomerated particles in the falling curtain is insufficient to cover more than half of the surface of the belt exposed to it. 6. The device for carrying out the method according to claim 1, characterized in that it has means for generating at least one gel-shaped or pasty stream of dental composition, means for generating a stream of agglomerated particles to be distributed in the dentifrice and for aligning this stream to a surface of the Stream of the dental composition holding the agglomerated particles and means for controlling the relative feed rate and proportions of the dental composition and the agglomerated particles to be dispersed therein so that when the stream of agglomerated particles contacts the stream of dental composition, the agglomerated Particles are insufficient to cover the surface of the dental composition and the agglomerated particles adhere to the stream of the dental composition. 7. The device according to claim 6, characterized in that the means for generating the stream from gel-like or pasty dental composition produce a gel ribbon and comprise an extruder for pulling out the gel ribbon in a direction with a horizontal component, the means for generating the stream from agglomerated particles Form a curtain from these particles and comprise a screw or screw conveyor device and means for distributing the supplied agglomerated particles into a curtain of slightly less width than the 60 side of the gel band and the device comprises a container above or in which the means for extracting the gel and the means for producing the curtain from agglomerated particles are arranged. 8. The device according to claim 6, characterized in that the means for producing the curtain from agglomerated particles direct these particles downward so that they fall as a vertical curtain on the gel ribbon, the container has an outlet opening at its bottom, and the means for Alignment of the gel ribbon align it so that after the agglomerated particles have come into contact with and are held by the gel ribbon, the latter falls perpendicularly to the outlet of the container and the device comprises means for holding the container under vacuum, furthermore a screw pump and a static mixer, wherein the screw pump is arranged in connection with the outlet from the container in which the dentifrice containing agglomerated particles is manufactured, so that the dentifrice continuously without disintegrating or dissolving the agglomerated particles in the dentifrice from the Container and through the static mixing r can be pumped to a tube filling device without changing the appearance of the agglomerated particles in a way that is objectionable. 9. Apparatus according to claim 6 for carrying out the method according to claim 4, characterized in that it um2 means for generating a plurality of streams from gel-like or pasty dental composition 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 summarizes, means for generating a stream of agglomerated particles to be distributed in the dentifrice and for aligning this particle stream to a surface of a stream of gel-like or pasty dental material, means for controlling the relative loading speeds and the proportions of the gel-like or pasty dental material and those to be distributed therein agglomerated particles so that when the curtain of agglomerated particles comes into contact with the gel or paste stream, the agglomerated particles adhering to the gel or paste stream are not sufficient to cover the surface of that stream which is exposed to the falling curtain of agglomerated particles , and means for aligning a separate gel stream to adhere to the gel on which the agglomerated particles were deposited so that the particles are trapped between the two streams. 10. The device according to claim 9, characterized in that the means for generating streams of the dental composition form a pair of Geländer which flow continuously in directions with horizontal components, the means for generating a stream of agglomerated particles and their orientation on the surface of a Gel band drop the agglomerated particles in the form of a curtain down onto a flowing gel band and the means for controlling the relative feed speeds and proportions of the gel and the agglomerated particles control them in such a way that the amount of agglomerated particles falling in the form of a curtain is not sufficient, to cover more than half of the surface of the tape exposed to this curtain.