Therapeutic dentifirices in unlined container and method

© Start of patent period: 1981 02 15 Longest possible duration:

© Issued on: 1983 01 25 © inventor:

© dependence:

© Pamphlets considered to delineate the prior art:

AT 369 646

U.S. Patent 3,124,483

- 2 No. 3669646

The invention relates to a dentifrice pack, and more particularly to the composition of toothpastes contained, which also contain a controlled amount of alkaline earth metal ion in addition to other ingredients to prevent corrosion and staining when the composition is filled into uncoated aluminum tubing for a longer shelf life.

Generally speaking, there are two types of modern dentifrices on the market that can be described as opaque or clear gelatinous compositions.

Each of the two types of dentifrices mentioned is marketed in two different versions, namely A) as a cosmetic type and B) as an anticaries-effective type.

A cosmetic toothpaste is one that does not contain fluoride and is brought out for whitening and shining teeth. The second type, however, contains fluoride as

Anti-caries agents.

Such dentifrices as toothpastes usually contain an effective fluoride such as stannous fluoride, monofluorophosphate or their derivatives as well as polishes, humectants and other materials. These compositions are usually bottled in aluminum or plastic tubs for sale. Aluminum tubes are usually preferred, but it has been found that when such compositions contain an effective fluoride compound, a reaction with the interior of the uncoated aluminum tubes occurs, causing staining and other corrosive effects, apparently because of some kind of reaction or incompatibility. exists between the uncovered aluminum surface and one or more materials in the toothpaste. This incompatibility manifests itself in the form of gas evolution, puffing of the tube, corrosion and black spots on the inside of the uncoated aluminum container. Therefore, it is currently the usual practice in the trade in therapeutic toothpastes to coat the aluminum tube with a layer of plastic, lacquer or other material which significantly increases the cost of packaging and placing the toothpaste on the market.

Many previous attempts have been made to solve this problem because uncoated aluminum tubes are much more economical in use and much lighter than the coated tubes. For example, U.S. Patent Nos. 3,662,060 and 3,624,199 disclose compositions allegedly solving this problem. Further, U.S. Patent No. 3,678,155 discloses that monofluorophosphate ions 30 prevent the corrosion of unpainted aluminum tubes when the dentifrice contains ground α-aluminum hydrates as the abrasive. Also, U.S. Patent No. 3,864,471 describes the composition of a dentifrice comprising a monofluorophosphate and a polishing agent containing the latter alkaline earth metal carbonate and an insoluble alkali phosphate, clay or mixtures thereof, to minimize corrosion of uncoated aluminum containers. The aim of the invention is thus to overcome or at least reduce the difficulties mentioned.

According to the present invention, a new dentifrice pack is characterized in that it consists of an aluminum tube and a non-staining toothpaste therein containing a water-soluble alkaline earth compound and a fluoride-containing component, the stain preventing concentration

Alkaline earth ions 0.05 to 0.20 wt .-% of the toothpaste.

As noted above, since the introduction of anticaries agent-containing dentifrices, it has not been possible to prepare a salable product that could be filled into uncoated aluminum tubes because of the incompatibility problems 45 between the aluminum surface of the tube and the other components of the dentifrice passed, in particular the fluorides. Although much work has been done in an effort to address this problem, as demonstrated by the prior art discussed above, the problems persist in this area. The invention overcomes problems of this nature in an economically acceptable manner and provides a fluoride-containing toothpaste or dentifrice composition which can be filled into and sold in uncoated aluminum tubing.

According to the invention, it has been found that the problem of corrosion of uncoated aluminum tubes when in contact with anticaries dentifrice compositions

No. 3,669,646 can be achieved by adjusting a predetermined concentration of an alkaline earth metal ion in the toothpaste composition. The alkaline earth metal ion with which this invention is primarily concerned is, in particular, calcium, but magnesium or strontium may also be used. Calcium compounds are preferred because they are readily available and inexpensive and can be easily incorporated into the dentifrice. The metal ion can be added to the dentifrice or toothpaste mixture in any water-soluble form, such as nitrate, oxide, hydroxide or chloride. The most preferred material according to the invention comprises calcium nitrate, calcium oxide, calcium hydroxide and calcium chloride. It should be noted, however, that organic salts such as calcium acetate, calcium formate and the like. can also be used. Corresponding strontium and magnesium salts can also be used. The only limitations imposed by the alkaline earth metal salt are that it must be substantially soluble, must not cause any safety problems in the compositions, and must remain available to combat corrosion.

Of course, dentifrices and other dentifrice compositions are already known which contain calcium salts in considerable amounts, as taught, for example, by US Pat. No. 3,864,471, where a CaCO₃ Content of 40 to 50%, as well as US Pat. No. 3,624,199, according to which 20 to 75% CaCO₃ available. However, calcium carbonate is substantially insoluble and is not effective for preventing the corrosion of the tube. It is therefore an important aspect of the invention in the carefully controlled amount of water-soluble alkaline earth ion which is incorporated into the toothpaste composition. According to the invention, the controlled amount of alkaline earth metal ion present must be sufficient to have an effect and be available for corrosion prevention, but in an insufficient amount to stoichiometrically affect the availability of the fluoride in the toothpaste. According to the invention, it has been found that the amount of alkaline earth metal ion which must be present in order to prevent corrosion must be at least about 50 ppm or 0.005% by weight and not more than about 2000 ppm or 0.02% by weight. may be used to avoid influencing the availability of fluoride. Therefore, the concentration of alkaline earth metal ion present is from 50 to 2000 ppm or from 0.005 to 0.02% by weight of the dentifrice.

As mentioned above, the alkaline earth ion may be incorporated in the toothpaste in the form of any water-soluble compound. However, it is also within the scope of the invention to supply the alkaline earth metal ion in combination with silicon dioxide or silicate abrasives and / or polishing agents. According to a feature of this embodiment, a defined structure, namely amorphous precipitated silica, may be added in sufficient amounts to provide the required alkaline earth metal ion, such as the Ca-ion, for the purpose of overcoming the problem of corrosion and the

To provide staining. This precipitated Si0₂ defined structure of dentifrice quality contains Ca ions on the surface of the SiO₂Particles of precipitated Si0₂Abrasive, polisher or thickener.

The precipitated SiO₂ Grades of defined structure and dentifrice grade as mentioned above are novel products available from the company JMH Corporation 40 and described, for example, in U.S. Patent Nos. 3,960,586 and 3,928,541 and others treated with an alkaline earth salt to incorporate alkaline earth ions into the composition. The products described in the cited patents are precipitated silica or SiO₂ Pigments, which are prepared by acidification of an alkali metal silicate such as Na silicate with an acid such as HjSO ,, in the presence of a salt or electrolyte such as Na₂S0₉ , The precipitated SiO₂Types that arise in this reaction, in the Na₂SO_H is a necessary reagent, may be referred to as sulfate liquor products. After the production of Si0₂ in the form of a wet cake and after washing, it is then reslurried in water and treated with a soluble alkaline earth compound such as Ca (OH)₂ , CaO, Ca (NO₃ )₂ or CaCl₂ treated, u.zw. in sufficient quantities, the required amount of alkaline earth ions 50 directly into the Si0₂ contribute. The reaction of SiO₂ with the alkaline earth metal is carried out at room temperature and with stirring. The amount of alkaline earth ions introduced is sufficient to provide the required amount of these ions in the dentifrice, but is consistent with any desired amount added directly to the dentifrice composition

- 4 No. 3669646. Alkaline earth metal ions.

So we see that the amorphous Si0₂Material is pretreated with the critical amount of alkaline earth material and then the toothpaste composition in the required and desired amounts is given. This SiO₂ Compositions give good cleaning properties at RDA values ​​between 200 to 400 (RDA - Grabbenstetter et al., Journal of Dental Research, 37,

1060, 1958).

The precipitated SiO₂Types used in the present invention may preferably be prepared by charging a reaction vessel with a 3 to 15% by weight aqueous solution of an alkali metal sulfate and adding an alkali metal silicate solution, preferably a Na silicate solution, to the reaction vessel to obtain a p ^ Value of about 8 to 10.4. This leads to a prepolymerization of the alkali metal silicate. The aqueous Na silicate solution should have a silicate concentration in the range of about 10 to 25% by weight, preferably 18 to 22% by weight, and for the best results, the composition Na₂O. 2.6 SiO₂, The aqueous solution is then heated to 66 to 83 ° C; with continuous stirring, the solution is then acidified by adding the aqueous solution of a mineral acid of a concentration of about 10 to 25% by weight to a substantially constant pi value in the range of about 8.0 to 10.4. Preferably, the mineral acid and the alkali silicate are added simultaneously as described in U.S. Patent No. 3,960,586. For the production of the precipitated silica or of the precipitated SiO₂For example, the disclosure of U.S. Patent Nos. 3,960,586 and 3,928,541 are intended to form part of the present disclosure. The mineral acid is preferably H₂SO_kbecause this gives the best results, but as known and also described in US Pat. No. 3,960,586, other acidulants such as nitric acid, phosphoric acid, hydrochloric acid, carbonic acid and the like. be used. The period during which the alkali silicate and / or the sulfuric acid added or can be predetermined in the reaction vessel, and is generally based on the volume of the reaction vessel and the difficulties of controlling the volume in the reaction vessel and the temperature and the stirring process. After the additions have been completed, the acid used for acidification is further added until the pi value of the slurry falls below about 6.0, and is preferably in the range of about 4.8 to 5.0. The resulting slurry then provides the precipitated SiO₂contained in the reaction medium.

After a p.sub.i value of less than 6.0 has been obtained, the slurry for a

Digestion time of 10 to 30 min at a temperature of 10 to 30 ° C above the reaction temperature and the p_H~ Value of the conversion is set again as required. The resulting slurry is then filtered and washed with additional water to remove any byproduct of the reaction, such as sodium sulfate, dissolved in the SiO₂Product may be included.

At the time of filtering and washing the wet SiO₂ Cake is subjected to the treatment with the alkaline earth metal ions to obtain the novel abrasive products used in the present invention. Then, the washed, wet cake is reslurried in its own water or with the addition of fresh water, at ambient temperature and with stirring. While stirring, this slurry is then treated with enough alkaline earth ions and in particular Ca ions in the form of a substantially soluble salt to give enough alkaline earth ions corresponding to about 30 to 2000 ppm, intimately associated with the Si0₂ to provide, this amount refers to 100 parts of dentifrice. The amounts of added alkaline earth ions are based on the total weight of the dry product, which is obtained in the form of a moist cake, ie on recoverable solid. Since the amount of abrasive in dentifrice compositions can vary, so does the amount of alkaline earth salt.

The alkaline earth metal ion added at this time is preferably the Ca ion, since this is easily available, costing little and the SiO₂ can be easily incorporated. The Ca ions can at this stage the SiO₂ in any substantially water-soluble form such as nitrate, oxide, hydroxide or chloride, but lime or calcium hydroxide is preferred. It should be used food grade salts. By soluble salt is meant any rather soluble Ca salt and can be used since it is only necessary to supply extremely small amounts of Ca ions to the mixture. It is also possible to use organic salts such as potassium zium acetate, calcium formate and the like. be used. Likewise, the corresponding strontium and magnesium salts can be used. The only limitation that governs the choice of alkaline earth salt to be added is that it must be sufficiently water-soluble to provide the ions, that there are no problems with the safety of the resultant

Toothpastes exist and that they have the required compatibility with the fluoride.

After treatment with the alkaline earth ion, the cake slurry is then vigorously stirred for 10 to 20, preferably 15 minutes, to determine the presence of an effective amount of the alkaline earth metal for treatment on the surface of the SiO₂ To ensure abrasion. The resulting product is then filtered, spray dried, preferably with an inlet temperature of 483 ° C and an outlet temperature of 122 ° C, as is well known, and then ground to the desired fineness. The precipitated amorphous silicas which are preferably used in this embodiment may be characterized by the following combination of properties:

<td>Oil absorption, stripping method (cm³/100 g)</td><td>=</td><td>80</td><td>120</td>

<td>BET surface area (m²/G)</td><td>=</td><td>75</td><td>235</td>

<td>MSA average aggregate size (μ)</td><td>=</td><td>1</td><td>10</td>

<td>Bulk density (g / m³)</td><td>=</td><td>0.16 -</td><td>0</td>

It will be understood, however, that other types of silica-based polishes may also be used in the present invention, including xerogels, as described in U.S. Patent No. 3,538,230,20. Commercially available xerogels such as Syloid 63 (manufactured by Davison Div of WRGrace &amp; Co.) may be used when incorporated with controlled amounts of Ca or other alkaline earth ions or pretreated with such ions as described. Also, Na aluminosilicate abrasives can be used in the preparation of the toothpastes according to the invention when these Na aluminosilicate materials are combined with the critical amounts of alkaline earth metals as described.

As is known, a dentifrice may contain, for example, humectants and binders in order to obtain a smooth texture and good flow properties. The particular formulations of toothpastes are well known and are described, for example, in U.S. Patent Nos. 2,994,642, 2,538,230, and numerous publications.

Most toothpastes use one of several common phosphate materials as a polishing agent. Examples of phosphate polishes are dicalcium phosphate, anhydrous dicalcium phosphate, tricalcium phosphate, thermally converted dicalcium phosphate, and insoluble sodium metaphosphate. The amount of phosphate materials added to the compositions ranges between about 5 and 60 weight percent.

The most commonly used moisturizers in toothpastes are glycerol and sorbitol.

Also, propylene glycol is used in small amounts and to a very small extent. The primary function of the humectant as part of the liquid phase is to retain the moisture, which provides a good structure and maintains a pleasing glossy appearance when the paste is exposed to the air.

The binder is used to prevent separation of the liquid and solid phases. The most commonly used binders are marine plant colloids and synthetic cellulose derivatives, especially carrageenan and Na-carboxymethylcellulose. Other binders such as gums have been used as well as combinations of these binders.

As aqueous dispersions of natural as well as synthetic organic

Binders are exposed to attack by microorganisms or mold, a relatively small amount of a preservative is added to the paste. Examples of preservatives industrially used are esters of p-hydroxybenzoates.

The function of the cleaning agents in the toothpaste is to provide a better cleaning effect due to the reduction of the surface tension and the foaming action in the mouth. The detergents used include Na lauryl sarcosinate, Na lauryl 6 No. 3669646 sulfate, Na alkyl sulfoacetate. and Na dioctyl sulfosuccinate.

Since the flavorings for the toothpaste represent the most important single factor in terms of the consumer's response, great care has been taken in the selection of balanced mixtures of various essential oils. These are rarely, if ever, used in their pure form. Combinations of major flavors are wintergreen, peppermint and sassafras, which are applied with secondary oils such as allspice, clove oil and anise.

Saccharin-Na and Na-cyclamate are used extensively to improve the taste and flavor of the toothpaste. The synthetic sweeteners may be used in combination to achieve optimum sweetness in the absence of off-taste. Their desired properties are obtained at very low concentrations and therefore they also have a negligible effect on the consistency of the toothpaste.

Since water is such a common ingredient, it is important in the preparation of stable toothpaste compositions to use substantially pure water therefor. It is common to demineralize the water used.

It is also within the scope of the invention to provide the correct amount of alkaline earth metal in the toothpaste by pretreating the water with calcium or other alkaline earth metal so that it can serve as the source of the alkaline earth metal.

The invention is applicable in the context of all anticaries dentifrices, including those containing alkali metal fluorides such as sodium fluoride, sodium monofluorophosphate, stannous fluoride and the like, all of which are well known.

In general, these dentifrices contain from 5 to 50 weight percent polishing agent, up to about 1 weight percent fluoride or fluoride containing agent, from about 30 to 40 weight percent deionized water; the rest form carrier materials for the liquid phase such as glycerol, sorbitol and the like. As already indicated above, the composition according to the invention also contains from 0.005 to 0.20% alkaline earth metal ion, preferably calcium ion, based on the toothpaste composition. It has been found that this amount of alkaline earth is sufficient to overcome the problems associated with staining and corrosion of uncoated aluminum tubes, but is too small to interfere with the availability of the fluoride, and therefore not the therapeutic effect of the dentifrice composition.

The Technical Bulletin Pigments, Synthetic Products for Toothpastes (Legussa), No. 9, discloses a polish Aerosil 200 for use in chalk toothpastes, and it is noted on page 8 of this bulletin that in toothpastes which are the cheaper Polishes, namely chalk, the use of Aerosil 200 is recommended because then the less expensive unpainted aluminum tubes can be used, because the corrosion protection for these tubes is caused by the formation of minimal amounts of insoluble calcium silicate from this composition. A minimum of 1% Aerosil 200 is required. However, it is also stated on page 8 of the same Bulletin that even with the use of Aerosil 200 it is not possible to achieve effective corrosion protection on untreated aluminum tubes when the toothpaste composition contains fluorine in the form of fluoromonomophosphate.

The cited reference also teaches on page 8 that when added from 3 to 5 wt .-% Light Hydrated Alumina W-16 to the fluoride toothpaste corrosion protection can be obtained. It has now been found according to the invention that fluoride-containing toothpastes can be filled into uncoated aluminum tubes when these toothpastes contain a predetermined amount of alkaline earth metal ion.

In connection with the incorporation of siliceous products into the toothpaste packagings according to the invention, it should be noted that all silicic acid products and raw materials contain the same amounts of calcium. Thus, commercial communications relating to the xerogels sold to the name of Syloid indicate the presence of 0.01% Ca as CaO. This corresponds to 0.007% Ca or up to 70 ppm in Syloid 63. However, since only amounts of up to 35% by weight of the silica products can be added to the dentifrice compositions, it can be deduced that the resulting dentifrices can contain only 0.0035% CaO or 25 ppm Ca, which is an insufficient quantity for corrosion protection. It should also be noted that the above described, from the company JMHuber Corp. sold precipitated silica 7 No. 3669646

Products have a tendency to uptake or to react with Ca ions, making these products extremely suitable for combination with the proper amounts of Ca ions or for incorporation in toothpastes, as these SiO_a Products also have excellent abrasive properties for toothpastes.

The described silica abrasives are used in concentrations of 15 to 30% by weight in the dentifrice. Therefore, they should contain at least 168 ppm Ca at 30% by weight and 336 ppm at 15% by weight to ensure the minimum amount of Ca. But they can also contain up to 7000 ppm or more.

The following specific examples illustrate the invention in comparative manner. The compositions were prepared in the usual way and all amounts of the various ingredients are by weight unless otherwise stated. In the following examples and throughout the specification, parts are parts by weight unless otherwise specified.

Examples:

In the following examples, toothpastes were prepared and compared to commercial products or control samples. In evaluating the toothpastes, a scheme was used to classify the inner wall of the tube and determine the presence or absence of staining and corrosion. As a basis for the scheme, each composition was prepared and then aged at 49 ° C for 9 weeks. Percent soluble fluoride ion and tube compatibility data were periodically determined during the 9 week storage stability period. 20 In this test, each aging for three weeks under the aging conditions (49 ° C) is about one year aging at room temperature. During the tests, the uncoated tubes containing the composition were periodically opened and checked for staining or corrosion on the inner wall of the tube. The following classification was used for the classification of the Tubeneigenschaften:

<td>25</td><td>classification</td><td>Tube inner wall</td>

<td></td><td>10</td><td>no air, no discoloration of the wall</td>

<td></td><td>8-9</td><td>no air, light gray spot on the wall</td>

<td></td><td>6-7</td><td>Air on the wall, light gray spot on the Wall</td>

<td>30</td><td>4-5</td><td>Air on the wall, gray spot on the wall</td>

<td></td><td>2 - 3 1</td><td>Air on the wall, dark gray spot on the wall wall Air on the wall, black spot with Pitting on the wall</td>

In all the following examples, the alkaline earth metal was Ca and it became soluble ++

Ca (NO₃h to provide the amount of Ca indicated for each composition.

Examples 1 to 4: dentifrice compositions in which calcium has been added to the dentifrice

The following toothpastes were made 40 with a low-silica polishing agent and a known amount of Ca⁺⁺ added to the composition to impart compatibility properties to the tube.

- 8 No. 3669646

<td rowspan="3"></td><td colspan="4">Examples 1 to 4</td>

<td colspan="4">toothpaste</td>

<td>1</td><td>2</td><td>3</td><td>4</td>

<td>Na monofluorophosphate</td><td>0.76</td><td>0.76</td><td>0.76</td><td>0.76</td>

<td>low-silica silicic acid</td><td>30.00 *</td><td>29.970</td><td>29.941</td><td>29.587</td>

<td>Ca⁴¹ as water-soluble Ca (N0₃)₂ , 4 H_aO **</td><td>0.00</td><td>0.0295</td><td>0.059</td><td>0.413</td>

<td>glycerin</td><td>23.00</td><td>23.00</td><td>23.00</td><td>23.00</td>

<td>Na carboxymethylcellulose</td><td>1.30</td><td>1.30</td><td>1.30</td><td>1.30</td>

<td>Hydrated clay</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>Na lauryl sulfate</td><td>2.00</td><td>2.00</td><td>2.00</td><td>2.00</td>

<td>Sodium benzoate</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na-saccharin</td><td>0.20</td><td>0.20</td><td>0.20</td><td>0.20</td>

<td>flavoring</td><td>0.90</td><td>0.90</td><td>0.90</td><td>0.90</td>

<td>Water (deionized)</td><td>rest</td><td>rest</td><td>rest</td><td>rest</td>

<td>A total of</td><td>100.00</td><td>100.00</td><td>100.00</td><td>100.00</td>

* Low-silica silica containing 5 ppm of Ca ** The conversion factor for Ca (N0₃)₂ , 4 H_aO to Ca is 5.9. The molecular weight of Ca (NO₃)₂ , 4 H_a0 is 236, the atomic weight of Ca 40. Therefore, 236 parts of Ca (NO₃)₂ , 4 H_aO 40 parts approx⁺⁺Ion or 236/40 or 5.9 parts Ca (NO₃)₂what a part Ca⁺⁺ corresponds to

In toothpastes 2, 3 and 4 was calcium nitrate, 4 H₂O, which corresponds in composition to a Ca ** level of 0.0295 / 5.9 or 50 ppm (0.005%) or 100 ppm (0.01%) or 700 ppm (0.07%). The Tuhen compatibility values ​​for these examples are given in Table I below.

Table 1

Classification of physical properties Examination of aging at 49 ° C

<td rowspan="2">composition</td><td colspan="5">weeks</td>

<td>0</td><td>1</td><td>3</td><td>6</td><td>9</td>

<td>1</td><td>10</td><td>4</td><td>3</td><td>3</td><td>1</td>

<td>2</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>3</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>4</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

- 9 No. 3669646

From the above data it is clear that Tube 1 was unacceptable in its compatibility properties because it did not contain the critical minimum amount of Ca in the anticaries toothpaste.

Examples 5 his 8:

The following toothpastes were prepared in which the content of Na monofluorophosphate in each 0.1% fluoride ion is equivalent.

<td rowspan="2">Composition no.</td><td colspan="4">parts</td>

<td>5</td><td>6</td><td>7</td><td>8th</td>

<td>Na-monofluorophosphate</td><td>0.76</td><td>0.75</td><td>0.76</td><td>0.76</td>

<td>Low-structural silica</td><td>30.00 (A)</td><td>30.00 (B)</td><td>30.00 (0</td><td>30.00 (D)</td>

<td>glycerin</td><td>23.00</td><td>23.00</td><td>23.00</td><td>23.00</td>

<td>N a-carboxymethylcellulose</td><td>1.30</td><td>1.30</td><td>1.30</td><td>1.30</td>

<td>Hydrated clay</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>Na lauryl sulfate</td><td>2.00</td><td>2.00</td><td>2.00</td><td>2.00</td>

<td>Sodium benzoate</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na-saccharin</td><td>0.20</td><td>0.20</td><td>0.20</td><td>0.20</td>

<td>flavorings</td><td>0.90</td><td>0.90</td><td>0.90</td><td>0.90</td>

<td>Water (deionized)</td><td>40.34</td><td>40.34</td><td>40.34</td><td>40.34</td>

<td>A total of</td><td>100.00</td><td>100.00</td><td>100.00</td><td>100.00</td>

<td>(A)</td><td>the</td><td>featureless</td><td>silica</td><td>the</td><td>composition</td><td>5</td><td>contained</td><td colspan="3">5 TpM approx</td>

<td>(B)</td><td>the</td><td>featureless</td><td>silica</td><td>the</td><td>composition</td><td>6</td><td>contained</td><td>168</td><td>ppm</td><td>Ca</td>

<td>(C)</td><td>the</td><td>featureless</td><td>silica</td><td>the</td><td>composition</td><td>7</td><td>contained</td><td>406</td><td>ppm</td><td>Ca</td>

<td>(D)</td><td>the</td><td>featureless</td><td>silica</td><td>the</td><td>composition</td><td>8th</td><td>contained</td><td>688</td><td>ppm</td><td>Ca</td>

The structurally silicic acids used in Examples 5, 6, 7 and 8 were characterized by the following combinations of properties:

<td>10</td><td>Oil absorption - dryness method (cm³/ 100 mg)</td><td>80</td><td>- 120</td>

<td></td><td>BET surface area (m²/G)</td><td>75</td><td>- 235</td>

<td></td><td>MSA average aggregate size (μ)</td><td>1</td><td>- 10</td>

<td></td><td>Bulk density (g / cm³)</td><td>0.16</td><td>- 0.48</td>

The Ca-treated structurally silicas of compositions 5, 6, 7 and 8 were prepared by the following procedures:

Dry Na sulfate was added to 10.0 gallons of water in a 200 gallon reaction vessel so that the Na sulfate concentration in the reaction medium was 10%. The reaction medium was then adjusted to 9.0 by addition of Na silicate. The reaction temperature was 65 ° C. The Na silicate solution had a molar ratio SiO_a : N / A_aO of 2.5 and a concentration of 2.0 lb / gallon. The Na silicate was added to the reaction medium for 4 minutes. At this time, the addition was stopped and sulfuric acid of 11.4% concentration was added to the reaction medium until the pH of 9.0 was reached. At this time, the Na silicate and sulfuric acid solution were added simultaneously over 35 minutes. At the end of this 35 min period, the silica addition was discontinued and the acid addition was continued,

- 10 # 3669646 until a slurry with a p ^ value of 5.5 was obtained. The sample was aged at 77 ° C for 20 minutes, the formed wet cake was taken out and washed.

This wet cake was then divided into 4 separate portions and treated in the following manner:

Each sample of the washed filter cake was then reslurried without addition of water at room temperature and with stirring. While stirring, the slurry was washed with sufficient slaked lime [Ca (OH)_a food grade] to ensure the extent of Ca ion treatment described for compositions 5, 6, 7 and 8. The amount Ca (OH)₂ was calculated on the weight of the recoverable dry product in the wet cake. After treatment with the Ca ions, the slurry of the cake was stirred vigorously for 15 minutes to achieve the desired level of Ca ion deposition on the surface of the SiO₂ Ensure abrasive. Each product obtained was then spray dried, ground and classified at an inlet temperature of 483 ° C and an outlet temperature of 122 ° C.

Compositions 5, 6, 7, and 8 were aged at 49 ° C for 9 weeks, and Tu15 ben tolerances were periodically determined during this 9-week storage period. The results regarding the tube compatibility properties are given in Table 2 below.

Table 2

Classification of fitness characteristics - aging at 49 ° C

<td rowspan="2">Composition:</td><td colspan="5">weeks</td>

<td>0</td><td>1</td><td>3</td><td>6</td><td>9</td>

<td>5</td><td>10</td><td>4</td><td>3</td><td>3</td><td>1</td>

<td>6</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>7</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>8th</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

From Table 2 it can be seen that dentifrice composition 5 caused a high level of black spot and pitting on the tubal wall at the end of the 9-week study. Compositions 6, 7 and 8 were stable and had excellent tube compatibility properties. It is thus perfectly clear that when a silica polishing agent has a critical minimum amount of Ca⁺⁺ It does not corrode uncoated aluminum tubes.

Examples 9 to 11: Stabilization of fluoride-containing xerogel toothpastes with calcium 25 Fluoride toothpastes were prepared with xerogel polishes. All compositions contained a known amount of Ca ions (added as water-soluble calcium nitrate) with the exception of Composition 9. The compositions were prepared in a conventional manner and filled into uncoated aluminum tubes. All amounts of the various ingredients are given by weight unless otherwise specified.

The following toothpastes were prepared: The Na monofluorophosphate content in each corresponded to 0.1% fluoride ion.

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<td rowspan="2">Assets</td><td colspan="3">parts</td>

<td>9</td><td>10</td><td>11</td>

<td>Glycerin (99.5% solution)</td><td>22.00</td><td>22.00</td><td>22.00</td>

<td>Sodium benzoate</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na-saccharin</td><td>0.20</td><td>0.20</td><td>0.20</td>

<td>CMC - 7 MF</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>N a-Monof luorphospha t</td><td>0.76</td><td>0.76</td><td>0.76</td>

<td>Water (deionized)</td><td>36.54</td><td>36.54</td><td>36.54</td>

<td>Xerogel (Syloid 63)</td><td>35,00</td><td>34.82</td><td>34,70</td>

<td>Hydrated clay</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>TiO₂</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na lauryl sulfate</td><td>1.50</td><td>1.50</td><td>1.50</td>

<td>Calcium nitrate. 4 H_aO *</td><td>0.00</td><td>0.18</td><td>0.30</td>

<td>flavorings</td><td>1.00</td><td>1.00</td><td>1.00</td>

* The 0.18 and 0.30% calcium nitrate, respectively. 4 H_a 0 in compositions 10 and 11 correspond to 0.18 / 5.9 or 0.03% Ca (300 ppm Ca) and 0.30 / 5.9 or 0.05% Ca (500 ppm Ca)

It can be seen that the composition of Example 9 contained no Ca. Tuber properties were then determined once the dentifrices had been aged for 9 weeks; they were graded at intervals of 1, 3, 6 and 9 weeks. The following Table 3 shows the extent of corrosion or staining of the uncoated Al tubes.

Table 3

Tube compatibility properties Examination during storage at 49 ° C

<td rowspan="2">composition</td><td colspan="5">weeks</td>

<td>0</td><td>1</td><td>3</td><td>6</td><td>9</td>

<td>9</td><td>10</td><td>7</td><td>6</td><td>6</td><td>5</td>

<td>10</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>11</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td>

From the values ​​in Table 3, it is clear that the compositions according to Examples 10 and 11 have excellent tube compatibility properties. Note that rating 10 does not indicate any discoloration of the uncoated container. Since the composition 9 did not contain the critical amount of Ca, it was found that the compatibility properties were completely unacceptable after 9 weeks storage at 49 ° C.

According to the manufacturer, the Xerogel Syloid 63 has the following properties:

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Loss on ignition 6.5

Pg of the 5% slurry 4.1% Si0₂ in annealed base material 99.5

Particle size, μ 9.0

Surface, m²/ g 625

Oil absorption, + / 45.4 kg 60

Bulk density, g / cm³ 0.46

In addition to these properties, the Syloid 63 had the following chemical composition (manufacturer's information):

Dry-based chemical analysis o, p

<td>Aluminum as A1₃O₃</td><td>0.04</td>

<td>Titanium as TiO₂</td><td>0.03</td>

<td>Calcium as CaO</td><td>0.01</td>

<td>Sodium as Na₂O</td><td>0.02</td>

<td>Zircon as ZrO₂</td><td>0.01</td>

<td>Trace elements (oxides)</td><td>0.02</td>

Example 12: Effect of Ca on commercial toothpastes

An anti-caries clear gel dentifrice (I) is filled into a coated container to prevent corrosion and staining on the inside wall of the tube.

Another commercial product (II) is also filled in a coated container to prevent corrosion and staining on the inner wall of the tube.

In order to test the problem of the effectiveness of Ca ++ addition in solving the tube compatibility problem, both (I) and (II) were purchased and each paste was divided into three parts.

The toothpaste (I) was divided into parts Α, B and C. Part A was packed in an uncoated aluminum tube without any Ca ++ addition to the paste. Parts B and C were | | mixed with a known amount of Ca and then packed in uncoated aluminum tubes.

The toothpaste (II) was also divided into three parts D, E and F. The part. D was filled into an uncoated aluminum tube without the addition of Ca. To Parts E and F, a predetermined amount of Ca was added. The values ​​obtained with the compositions (I) and (II), respectively, wherein these compositions were filled into uncoated containers, are given in Table 6 and the respective compositions are the following:

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Example 12

<td>composition</td><td>% Ca *</td><td>% commercial dentifrice</td>

<td>A</td><td>0.00</td><td>100.00 (I)</td>

<td>B</td><td>0.10</td><td>99.41 (I)</td>

<td>C</td><td>0.16</td><td>99.16 (I)</td>

<td>D</td><td>0.00</td><td>100.00 (II)</td>

<td>e</td><td>0.10</td><td>99.41 (II)</td>

<td>F</td><td>0.16</td><td>99.16 (II)</td>

* Admitted as Ca (N0₃ )_a , 4 H_a0

Table 4

Tube compatibility properties Aging test at 49 ° C

<td rowspan="2">composition</td><td colspan="4">weeks</td>

<td>1</td><td>3</td><td>6</td><td>9</td>

<td>A</td><td>5</td><td>4</td><td>3</td><td>1</td>

<td>B</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>C</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>D</td><td>5</td><td>5</td><td>4</td><td>2</td>

<td>e</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>F</td><td>10</td><td>10</td><td>10</td><td>10</td>

Compositions B, C, E and F have excellent tube compatibility properties as compared to compositions A and D. The addition of Ca thus helped to stabilize these dentifrices.

Examples 13 to 17:

The following toothpastes were prepared to illustrate the use of Na aluminosilicates (SAS) as a filming agent. The composition of Example 13 was used as a blind + 4 * ++ experiment, with no Ca added. Known amounts of Ca were added to the compositions of Examples 14, 15, 16 and 17. The compositions were as follows:

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<td rowspan="2">composition</td><td colspan="5">parts</td>

<td>13</td><td>14</td><td>15</td><td>16</td><td>17</td>

<td>Glycerine (99.5%)</td><td>22.00</td><td>22.00</td><td>26.00</td><td>25,00</td><td>30.00</td>

<td>Sodium benzoate</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na-saccharin</td><td>0.20</td><td>0.20</td><td>0.20</td><td>0.20</td><td>0.20</td>

<td>CMC</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>Na-Monof luorphospha t</td><td>0.76</td><td>0.76</td><td>0.76</td><td>0.76</td><td>0.76</td>

<td>Calcium nitrate. 4 H_aO *</td><td>0.00</td><td>0.20</td><td>0.20</td><td>0.20</td><td>0.24</td>

<td>Deionized water</td><td>36.54</td><td>36.34</td><td>39.54</td><td>38.54</td><td>43.30</td>

<td>SAS Polisher</td><td>35.00CA)</td><td>35,00 (A)</td><td>27.80 (B)</td><td>29.80 (0</td><td>20.00 (D)</td>

<td>Hydrated clay</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td>

<td>TiO ₂</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td>

<td>Na lauryl sulfate</td><td>1.50</td><td>1.50</td><td>1.50</td><td>1.50</td><td>1.50</td>

<td>flavorings</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td><td>1.00</td>

It should be noted that in compositions 14, 15, 16 0.2% Ca (NO₃)₂ , 4 H_aO, 0.03% Ca-lon and 0.24% Ca (N0₃)₂ , 4 H_aO in composition 17 correspond to 0.04% Ca ion

CA) had the SAS product used in compositions 13 and 14

<td></td><td>on</td><td>SiO</td><td>_a : Al₂0₃-Relationship</td><td>from</td><td>11.0</td><td></td><td></td><td></td>

<td>(B)</td><td>The</td><td>in</td><td>the composition</td><td>15</td><td>used</td><td>SAS Product</td><td>would have</td><td>on</td>

<td></td><td>SiO₂</td><td></td><td>al₂0₃-Ratio of</td><td>2.5</td><td></td><td></td><td></td><td></td>

<td>(C)</td><td>The</td><td>in</td><td>the composition</td><td>16</td><td>used</td><td>SAS Product</td><td>would have</td><td>on</td>

<td></td><td>SiO_a</td><td></td><td>A1₂O₃-Ratio of</td><td>130</td><td></td><td></td><td></td><td></td>

<td>(D)</td><td>The</td><td>in</td><td>the composition</td><td>17</td><td>used</td><td>SAS Product</td><td>would have</td><td>on</td>

<td></td><td>SiO₂</td><td></td><td>al₂0₃-Ratio of</td><td>400</td><td></td><td></td><td></td><td></td>

The preferred Na aluminosilicates (SAS) have the following molar chemical composition:

x na_aO. y al_a0₃ , z SiO_a , w H₂0 where x, y, z and w are the moles of Na₂0 or Al₂0₃ or SiO₂ or H_aO mean.

When y is set to 1, the value of z corresponds to SiO₂ : A1₂O₃Molar ratio of SAS. The low-SAS polishing and abrasives have a Si0₂ : Al₂ O₃ Ratio or z values ​​of 2.5 to 400.

The properties of SAS polishes are the following:

Oil absorption, rub-out method (cm³/ 100 g) = 75-125

BET surface area (m^a/ g) = 50-300

MSA average aggregate size (μ) = 1 - 10

Bulk density (g / cm³)

0.56

0.19

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Compositions 13 to 17 were aged for 9 weeks at 49 ° C and the tube compatibility properties were evaluated at intervals of 1, 3, 6 and 9 weeks; the results are shown in Table 5 below.

Table 5

Tube compatibility properties, 49 ° C

<td rowspan="2">composition</td><td colspan="4">weeks</td>

<td>1</td><td>3</td><td>6</td><td>9</td>

<td>13</td><td>1</td><td>1</td><td>1</td><td>1</td>

<td>14</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>15</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>16</td><td>10</td><td>10</td><td>10</td><td>10</td>

<td>17</td><td>10</td><td>10</td><td>10</td><td>10</td>

Note that compositions 14 to 17 have excellent tube compatibility properties.