EP1149123B1 - Peroxidised polyorganosiloxanes (pos), one of the methods for preparing them and their use as bleaching agent in dental compositions - Google Patents

Abstract

The invention concerns polyorganosiloxanes (POS) grafted with peroxide functions and functions stabilizing the latter. Said stabilized peroxidised POS are designed to form a novel oxidizing system useful as bleaching agents, for example or dental or detergent compositions. The invention aims at and succeeds in providing peroxygenated bleaching agents more stable and more efficient than those known in prior art. The inventive stabilized and peroxidised POS correspond for example to the formula (a). The invention also concerns a method for making said peroxidised POS, the precursors thereof and their uses as bleaching agents in dental compositions (toothpaste or detergent compositions).

Description

The field of the invention is that of applicable peroxidized systems especially in money laundering. The oxidizing properties of these systems are more particularly appreciated in teeth whitening applications (e.g. toothpaste).

The peroxidized systems referred to in the context of this presentation are functionalized polymers.

The present invention relates to perorganized polyorganosiloxanes (POS) thus as one of their preparation processes.

The invention also relates to silicone precursors of these POSs. peroxides.

Finally, the present invention includes an application aspect which comprises the use of peroxidized POSs according to the invention as active ingredient in laundering. More specifically, the invention relates to dental compositions, for example toothpastes, including peroxidized POS as a bleaching agent.

It is known in the field of whitening, in particular dental whitening, to use hydrogen peroxide H ₂ O ₂ or its persalts (percarbonates, perborates, calcium peroxides). In the remainder of this description, H ₂ O _{2 will} designate H ₂ O ₂ as such and its persalts. The disadvantages of hydrogen peroxide are not negligible. First, H ₂ O ₂ must be used in high concentration to be effective. This point is particularly troublesome given the aggressiveness of H ₂ O ₂ . Second, we know that the bleaching action is linked to the oxygen-giving effect. However, this effect is not the predominant effect that can be obtained with hydrogen peroxide. The latter behaves essentially as a promoter of deleterious free radicals, which do not participate in the bleaching function and which would even rather tend to thwart it. Third, hydrogen peroxide has the disadvantage of being unstable.

There is therefore a clearly identified need for a peroxide substitute of hydrogen for these applications in the field of bleaching and in particular teeth whitening (toothpaste).

Selon ce brevet, le greffage de la fonction peracide sur le support inorganique en silice, est sensé permettre une stabilisation de la fonction peracide. En réalité, il s'avère que cette stabilité pourrait encore être améliorée. En outre, il est à craindre que ces silices peroxydées soient difficilement dispersibles dans des compositions relativement visqueuses telles que les dentifrices.In an attempt to resolve the above-mentioned problem, it has been proposed in US Pat. No. 5,698,326 peracid compounds constituted by an inorganic support formed by silica and carrying peracid functionalities. These compounds can be obtained by reacting silica substituted with a siloxylalkylamine residue with a trimellitic anhydride, the carboxylic function of the benzyl ring of which is then oxidized, to transform it into a peracid function. This corresponds to the following formula:

According to this patent, the grafting of the peracid function on the inorganic silica support is supposed to allow stabilization of the peracid function. In reality, it turns out that this stability could be further improved. In addition, it is to be feared that these peroxidized silicas are difficult to disperse in relatively viscous compositions such as toothpaste.

European patent application No. 796 874 relates to a process for the preparation of polymers comprising peroxycarboxylic groups. These peroxycarboxylic polymers are more specifically copolymers of N-vinylpyrolidone / maleic anhydride. The hydrogen peroxide that we react with this copolymer allows the transformation of the carboxyls derived from the anhydride into peroxycarboxylic functions. The performance of these copolymers peroxycarboxylates, in terms of bleaching, are not revealed by this request patent. Furthermore, it seems that in the teeth whitening application, the peroxycarboxylated copolymers lack selectivity with respect to the teeth. In addition, instability problems can be feared for teeth whitening applications of these copolymers.

PCT patent application WO 97/02 011 discloses dental oral compositions comprising conventional ingredients such as abrasives, binders, humectants, surfactants, sources of fluorine ions or other sweeteners, as well as two other essential ingredients for namely, on the one hand, an aminoalkylsilicone such as a polydimethylsiloxane comprising aminoalkyl units of the propylaminoethylamine type in the chains and at their ends and, on the other hand, a polydimethylsiloxane comprising pendant groups of polyoxyethylene and / or polyoxypropylene type and having a surfactant action.
There is no question in this document of polyorganosiloxanes functionalized with peroxide units. This oral composition is presented as having improved anti-plaque and anti-bacterial properties, which complement excellent cleaning performance. This oral composition can also comprise bleaching agents belonging to the family of inorganic peracid salts (persulfates, perborates, percarbonates and metal peroxides).
These oral compositions are not satisfactory in terms of stability, toxicity, selectivity with respect to the teeth and efficacy of bleaching by oxidation.

Polyorganosiloxanes comprising ester groups of peracids carboxylic acids have been described in GB 897,973 and US 3,726,943; they can be useful as vulcanizing agents, as polymerization initiator, as coupling agents ...

In such a state of the art, one of the essential objectives of the inventors was to develop a new oxidizing system usable in particular in the bleaching, this peroxidized oxidizing system is having to be more stable and more efficient than the systems known from the prior art.

Another essential objective of the invention is to provide a system for peroxidized bleaching especially for dental bleaching applications which allows to control the reactivity of the peroxide function, so as to limit as far as possible its transformation into aggressive free radicals.

Another essential objective of the invention is to provide a system for peroxidized bleaching usable in particular in dental bleaching and endowed with significantly improved storage stability.

Another essential objective of the invention is to provide a system for peroxide bleaching applied in dental bleaching (oral composition for treatment and maintenance of the teeth), having a better selectivity with respect to teeth to whiten.

Another essential objective of the invention is to provide an oxidizing system peroxidized, capable of being used as a controlled release system of oxidizing peroxide functions.

Another essential objective of the invention is to provide a process for obtaining of the aforementioned peroxidized oxidizing system, which is simple to implement and economic.

Another essential objective of the invention is to prescribe the use of the system peroxidized oxidant mentioned above, as a teeth whitening agent.,

Another essential objective of the invention is to provide a composition dental with an effective, stable and selective bleaching agent.

• dans laquelle :
• a+b+c=0 à 3
• a, b, c = 0 à 3
• R correspond à un ou plusieurs radicaux identiques ou différents, R étant choisi parmi les groupements monovalents hydrocarbonés, de préférence parmi les alkyles linéaires, ramifiés et/ou cycliques et/ou les aryles, et plus préférentiellement encore parmi les alkyles linéaires ou ramifiés en C₁-C₄ et les groupes phényle, xylyle et tolyle ;
• E correspond à un ou plusieurs substituants fonctionnels identiques ou différents entre eux, monovalents, choisis parmi les groupements hydrocarbonés (cyclo)aliphatiques et/ou aromatiques et/ou hétérocycliques et porteurs d'une ou plusieurs fonctions peroxyde d'acyle Fpo de formule
  
  avec X correspondant à H, à un halogène de préférence le chlore ou à un cation permettant de former un sel avec l'anion peroxyde d'acyle et choisi de préférence parmi les éléments des colonnes Ia et IIA de la classification périodique, et comportant éventuellement chacun une ou plusieurs fonctions Fstab stabilisantes de Fpo, identiques ou différentes entre elles et choisies parmi les fonctions susceptibles de se lier par l'intermédiaire de liaisons faibles avec les fonctions Fpo ;
• G correspond à un ou plusieurs substituants fonctionnels identiques ou différents entre eux et comportant chacun une ou plusieurs fonctions Fstab stabilisantes de Fpo, identiques ou différentes entre elles et choisies parmi les fonctions susceptibles de se lier par l'intermédiaire de liaisons faibles avec les fonctions Fpo ;
• avec les conditions selon lesquelles :
  • (i) . la concentration en fonctions [Fpo] exprimée par le ratio nombreFpo nombre total d'atomes de silicium dans le POS est définie comme suit :
  • Δ   0 < [Fpo]
  • Δ de préférence   0,01 ≤ [Fpo] ≤ 1,0
  • Δ et plus préférentiellement encore   0,1 ≤ [Fpo] ≤ 0,6.
  • (ii) . la concentration en % molaire en motifs siloxaniques T (a + b + c = 1) et/ou Q (a + b + c = 0) est définie comme suit :
  • Δ   0 ≤ [T et/ou Q] ≤ 20
  • Δ de préférence   0 ≤ [T et/ou Q] ≤10
  • Δ et plus préférentiellement encore,   0≤ [T et/ou Q] ≤ 8.

These objectives, among others, are achieved by the present invention which relates to new polyorganosiloxanes (POS) comprising siloxane units of formula (I) below: R at E b G vs SiO 4 - (a + b + c) 2

• in which :
• a + b + c = 0 to 3
• a, b, c = 0 to 3
• R corresponds to one or more identical or different radicals, R being chosen from monovalent hydrocarbon groups, preferably from linear, branched and / or cyclic alkyls and / or aryls, and more preferably still from linear or branched C alkyls ₁ -C ₄ and the phenyl, xylyl and tolyl groups;
• E corresponds to one or more functional substituents which are identical or different from each other, monovalent, chosen from (cyclo) aliphatic and / or aromatic and / or heterocyclic hydrocarbon groups and carrying one or more acyl peroxide functions Fpo of formula
  
  with X corresponding to H, preferably a halogen, chlorine or a cation making it possible to form a salt with the anion of acyl peroxide and preferably chosen from the elements of columns Ia and IIA of the periodic table, and optionally comprising each one or more Fstab stabilizing functions of Fpo, identical or different from each other and chosen from functions capable of binding via weak bonds with the Fpo functions;
• G corresponds to one or more identical or different functional substituents with one another and each comprising one or more Fstab stabilizing functions of Fpo, identical or different between themselves and chosen from the functions capable of binding via weak bonds with the Fpo functions ;
• with the conditions under which:
  • (i). the concentration of functions [Fpo] expressed by the ratio nombreFpo total number of silicon atoms in the POS is defined as follows:
  • Δ 0 <[Fpo]
  • Δ preferably 0.01 ≤ [Fpo] ≤ 1.0
  • Δ and more preferably still 0.1 ≤ [Fpo] ≤ 0.6.
  • (ii). the concentration in molar% of siloxane units T (a + b + c = 1) and / or Q (a + b + c = 0) is defined as follows:
  • Δ 0 ≤ [T and / or Q] ≤ 20
  • Δ preferably 0 ≤ [T and / or Q] ≤10
  • Δ and more preferably still, 0≤ [T and / or Q] ≤ 8.

These new peroxidized POSs stabilize the function acyl peroxide and to control its oxidative activity by restraining its activity production of free radicals. In addition, their bleaching and selectivity towards teeth makes them whitening systems particularly suitable and effective for dental oral compositions such only toothpaste.

Indeed, these silicones functionalized with Fpo acyl peroxide are endowed with a specific affinity for the constituent materials of teeth (in hydroxyapatite) so these are selective vectors specific to route the chemical whitening functions to the teeth. It goes without saying that optimizes the efficiency of said functions. It follows that it is possible to reduce the doses, which is entirely in line with the decrease in the aggressiveness of the agent laundering.

In addition, these peroxide functional silicones are hydrophobic and have so the advantage of preserving the Fpo functions of water, which is an element major instability for them.

The new peroxidized polyorganosiloxanes with Fpo functions can be linear and / or branched and / or crosslinked polymers according to the percentage by weight of DTQ siloxyl patterns which they include. Preferably, the peroxidized POSs according to the invention mainly comprise units D (a + b + c = 2) and more still preferentially are linear.

Each Fpo acyl peroxide function belongs to a peroxycarboxylic acid, halide - chloride - or salt residue.

As examples of groups X = cations, we can cite: Na ⁺ , K ⁺ , Ca ⁺⁺ , Mg ⁺⁺ ...

These peroxycarboxylic residues are linked to the silicon of the POS chain by a hydrocarbon ball joint (that is to say comprising in particular carbon and hydrogen atoms), aliphatic and / or alicyclic and / or aromatic and / or heterocyclic optionally comprising one or more heteroatoms: N, O, S ..., possibly.

• d'une part, le reste peroxycarboxylique,
• et d'autre part, la rotule,

forme le substituant fonctionnel E.
En pratique, la rotule est, par exemple, du type -alkyl-O-aryle (benzyle), -alkyl anhydride, -alkylimide-aryle (benzyle), entre autres.The set including:

• on the one hand, the peroxycarboxylic residue,
• and on the other hand, the patella,

forms the functional substituent E.
In practice, the ball joint is, for example, of the -alkyl-O-aryl (benzyl), -alkyl anhydride, -alkylimide-aryl (benzyl) type, among others.

The advantageous stabilizing action of Fstab on Fpo is a preferred characteristic of the functionalized POSs according to the invention. In accordance with the latter, the Fstabs are located on the functional substituents (pendant) E and / or G. Without this being limiting, it is preferable that the Fstabs are carried at least by the
or the E, so as to be close to the Fpo to be stabilized. It is not forbidden to think that the stabilizing effect of Fstab is thus improved.

• les motifs fonctionnels comportant de l'azote et/ou de l'oxygène et/ou du fluor, et/ou du soufre et/ou du phosphore ; les motifs carboxyliques, carboxylates, amides, imides, sulfonamides, hydroxyles, alcoxyles, amines ou organo-fluorés, étant préférés ;
• les motifs cationiques, de préférence ceux comprenant un ou plusieurs ammoniums quaternaires ;
• les motifs chélatants comportant une ou plusieurs fonctions éther et/ou une ou plusieurs fonctions amines, et/ou les motifs chélatants phosphonates et/ou sulfonates.

According to a preferred characteristic of the invention, the possible stabilization functions Fstab of the substituents E and / or G of formula (I) correspond to functions which can generate weak bonds (hydrogen bonds, eg) with Fpo, and selected in the group including:

• functional units comprising nitrogen and / or oxygen and / or fluorine, and / or sulfur and / or phosphorus; the carboxylic, carboxylate, amide, imide, sulfonamide, hydroxyl, alkoxyl, amine or organofluoric units being preferred;
• cationic units, preferably those comprising one or more quaternary ammoniums;
• chelating units comprising one or more ether functions and / or one or more amine functions, and / or phosphonate and / or sulfonate chelating units.

The optional functional substituents G each include, in addition to the one or more Fstab, a ball joint which ensures the connection with the silicone chain. The ball joints of the substituents G are identical or different from each other, which meet the same definition as that given above for the ball joints of substituents E.

• soit à partir de chlorosilanes ou d'alcoxysilanes portant les substituants E , de chlorosilanes ou d'alcoxysilanes portant des substituants G et de chlorosilanes ou d'alcoxysilanes portant les substituants R et/ou l'hydrogène, par cohydrolyse, polycondensation et polymérisation des produits hydrolysés en présence de diorganosiloxanes cycliques ou redistribution en présence de polydiorganosiloxanes...
• soit à partir de polydiorganosiloxanes fonctionnalisés par hydrosilylation de polydiorganosiloxanes hydrogénés à l'aide de précurseurs oléfiniques intégraux ou partiels des substituants fonctionnels E et G.
  Au sens du présent exposé, les termes "précurseurs oléfiniques intégraux ou partiels" correspondent respectivement :
  • au cas où le précurseur oléfinique est sous forme finale et n'a pas à subir d'autres greffages pour conduire à l'intégralité du substituant qui sera transformé en E ou G après peroxydation (rotule intégrale),
  • et au cas où la rotule des substituants E ou G est formée par plusieurs chaínons mis bout à bout et correspondant à des formes intermédiaires de synthèse, le précurseur oléfinique constituant le premier chaínon qui est lié, d'une part, à la chaíne silicone et, d'autre part, au chaínon suivant de la rotule.

The peroxidized POSs which are the subject of the invention can be obtained:

• either from chlorosilanes or alkoxysilanes carrying the substituents E, from chlorosilanes or alkoxysilanes carrying the substituents G and from chlorosilanes or alkoxysilanes carrying the substituents R and / or hydrogen, by cohydrolysis, polycondensation and polymerization of the products hydrolyzed in the presence of cyclic diorganosiloxanes or redistribution in the presence of polydiorganosiloxanes ...
• either from polydiorganosiloxanes functionalized by hydrosilylation of hydrogenated polydiorganosiloxanes using integral or partial olefin precursors of the functional substituents E and G.
  For the purposes of this description, the terms "integral or partial olefin precursors" correspond respectively:
  • in the case where the olefinic precursor is in final form and does not have to undergo other grafting to lead to the entirety of the substituent which will be transformed into E or G after peroxidation (integral ball joint),
  • and in the case where the ball joint of the substituents E or G is formed by several chains placed end to end and corresponding to intermediate forms of synthesis, the olefinic precursor constituting the first chain which is linked, on the one hand, to the silicone chain and , on the other hand, to the next link of the ball joint.

Without this being limiting, peroxidized POSs obtained by hydrosilylation of olefinic precursors of substituents E and G are preferred in accordance with the invention.
These hydrosilylation reactions can be carried out at a temperature of the order of 15 to 200 ° C, preferably of the order of 20 to 100 ° C, in the presence of a catalyst based on a metal from the group of platinum. Mention may in particular be made of the complex platinum derivatives described in US Pat. Nos. 3,715,334, 3,775,452, 3,814,730, 3,159,601, 3,159,662.
The quantities of platinum catalysts used are of the order of 1 to 300 parts per million, expressed as metal relative to the reaction medium.
The olefinic precursors used in these hydrosilylations do not comprise the acyl peroxide functions Fpo, but their non-peroxygenated forms F'po or any intermediate forms thereof. It is preferable in accordance with the invention to provide protection for the precursor functions F'po before hydrosilylation.
The POS grafted by hydrosilylation and carrying the F'po precursor functions, are optionally purified and then subjected to an oxidation which allows the transformation of the F'po functions into Fpo functions.

   dans laquelle :

• R¹ R³ représentant indépendamment un hydrogène, un hydroxyle ou un reste monovalent répondant à la même définition que celle donnée pour R supra ;
• R² représentent indépendamment l'hydrogène, un hydroxyle ou un reste monovalent répondant à la même définition que celle donnée pour R supra ;
•    2 ≤ m + n + o ≤ 300
  de préférence   3 ≤ m + n + o ≤ 50
  et plus préférentiellement encore   5 ≤ m + n + o ≤ 20
•    0 ≤ m ≤ 200
  de préférence   1≤ m ≤ 100
  et plus préférentiellement encore   1 ≤ m ≤ 10
•    0 ≤ n ≤ 50
  de préférence   1 ≤ n ≤ 10
  et plus préférentiellement encore   2 ≤ n ≤ 4
•    0 ≤ o ≤ 50
  de préférence   1 ≤ o ≤ 10
  et plus préférentiellement encore   2 ≤ o ≤ 4.

According to a preferred embodiment of the invention, the peroxidized POSs correspond to the formula ( II ) given below:

in which :

• R ¹ R ³ independently representing a hydrogen, a hydroxyl or a monovalent residue corresponding to the same definition as that given for R above;
• R ² independently represent hydrogen, a hydroxyl or a monovalent residue corresponding to the same definition as that given for R above;
• 2 ≤ m + n + o ≤ 300
  preferably 3 ≤ m + n + o ≤ 50
  and more preferably still 5 ≤ m + n + o ≤ 20
• 0 ≤ m ≤ 200
  preferably 1≤ m ≤ 100
  and more preferably still 1 ≤ m ≤ 10
• 0 ≤ n ≤ 50
  preferably 1 ≤ n ≤ 10
  and more preferably still 2 ≤ n ≤ 4
• 0 ≤ o ≤ 50
  preferably 1 ≤ o ≤ 10
  and more preferably still 2 ≤ o ≤ 4.

Δ R¹ R³ = alkyle en C₁-C₃, de préférence - CH₃

Δ R² = alkyle en C₁-C₃, de préférence - CH₃

Δ le ou les substituants fonctionnels E, comprennent à la fois des fonctions Fpo et Fstab.

Even more preferably, the polyorganosiloxanes are characterized in that:

Δ R ¹ R ³ = C ₁ -C ₃ alkyl, preferably - CH ₃

Δ R ² = C ₁ -C ₃ alkyl, preferably - CH ₃

Δ the functional substituent (s) E, comprise both Fpo and Fstab functions.

In practice, without this being limiting, the functional substituents E of Peroxidized POSs each include a ball joint comprising at least one pattern bicarboxylated and / or benzoxylated and / or imide.

The case where the ball joint (s) of the functional substituent (s) E comprise at least one bicarboxylic motif, corresponds to a preferred form of the invention in which the Fpo function is obtained from an anhydride which is transformed, on the one hand, in an acyl peroxide function Fpo and, on the other hand, in an acid function Fstab carboxylic stabilization of neighboring Fpo.

The peroxidized POSs according to the invention are stable and have a high power whitening.

avec X' répondant à la même définition que celle donnée pour X supra ;
et/ou par des restes anhydrides d'acide

According to another of its aspects, the present invention relates to a process for the preparation of POSs as defined above. This process is characterized in that it essentially consists in oxidizing the polysiloxane precursors of the targeted peroxidized POSs. This oxidation is carried out using at least one oxidant preferably chosen from the group comprising: H ₂ O ₂ , O ₂ , O ₃ and their mixtures, These peroxidized POS precursors of POS are distinguished from the targeted peroxidized POS in that they comprise one or more F'po functions, Fpo precursors and consisting of:
by carboxyl residues:

with X 'corresponding to the same definition as that given for X above;
and / or by acid anhydride residues

These F'po functions can be final or included in a cycle.

As indicated above, the polysiloxane precursors with functional F'po can be obtained by cohydrolysis of chlorosilanes and non-alkoxysilanes functionalized and chlorosilanes or alkoxysilanes functionalized with substituents E and G. The stage which follows the cohydrolysis can be a polycondensation and polymerization of hydrolysis products in the presence of diorganosiloxanes cyclic or a redistribution step in the presence of polydiorganosiloxanes. These classic POS syntheses by cohydrolysis / polycondensation / polymerization or by cohydrolysis / redistribution are described in particular in "W. NELL chemistry and technology of silicones. Academic Press Edition. 1968. "

According to a preferred alternative, the starting materials used can be hydrogenated polyorganosiloxanes which can be functionalized by reacting them according to a hydrosilylation reaction (addition with olefinic precursors of substituents E and G.). See above for more details on this hydrosilylation.

• porteurs de fonctions F'po anhydrides, l'oxydation étant effectuée à l'aide d'H₂O₂ en présence d'un catalyseur de type base forte, de préférence la potasse ;
• et/ou porteurs de fonctions F'po carboxyliques - de préférence benzoyles-, l'oxydation étant effectuée à l'aide d'H₂O₂ en présence d'un catalyseur de type acide fort.

According to a preferred characteristic of the invention, the peroxidized POS precursors which are subjected to oxidation in order to obtain targeted peroxidized POS are selected from polyorganosiloxane precursors

• carrying F'po anhydride functions, the oxidation being carried out using H ₂ O ₂ in the presence of a catalyst of the strong base type, preferably potassium hydroxide;
• and / or carriers of F'po carboxylic functions - preferably benzoyl-, the oxidation being carried out using H ₂ O ₂ in the presence of a catalyst of strong acid type.

Even more preferably, the polyorganosiloxane precursors carry functions F'po succinic anhydride linked to the silicon atoms by a ball joint - (CH ₂ ) ₃ -.

In accordance with the invention, it appeared particularly advantageous that the precursors - POS present before the oxidation step to transform the F'po en Fpo, a molar purity ≥ 90%, preferably ≥ 95%.

In practice, this purification step is carried out by any known and appropriate method such as, for example, devolatilization or fractional precipitation in an organic solvent such as methanol.
As regards more specifically the oxidation step, it has been seen that the oxidizing agents could be hydrogen peroxide, oxygen, ozone and their mixtures.

In the case where the oxidizing agent consists of hydrogen peroxide, the catalyst used can be a strong base, for example, a mineral base such as KOH or NaOH or even a strong acid, for example, a mineral acid such as H ₂ SO ₄ or organic such as MeSO ₃ H. The solvents used in these cases are, for example, ethyl acetate or Me SO ₃ H.

As soon as the oxidizing agent is oxygen, it is possible to use a catalyst comprising Co ²⁺ .

In practice, this oxidation step can take place at temperature and pressure room.

The peroxidized POSs according to the invention are particularly suitable as bleaching agent and more particularly as a bleaching agent teeth, taking into account their properties of selectivity with respect to non-toxicity teeth, of controlled reactivity of the Fpo peroxide functions (limitation of the production of free radicals), non-toxicity and high efficiency at low doses.

From which it follows that the present invention also relates to a dental composition (for example an oral composition) - in particular toothpaste - characterized in that it comprises peroxygenated POSs as defined above at as a bleaching agent.

• des POS peroxygénés
  à raison de 0,1 à 40 % en poids,
  de préférence de 0,1 à 10 % en poids,
  et plus préférentiellement encore de l'ordre de 1 à 5 % en poids ;
• des abrasifs polissants à raison de 5 à 40 % en poids,
  de préférence de 5 à 35 % en poids, ces abrasifs pouvant être notamment la silice, le carbonate de calcium précipité, le carbonate de magnésium, les phosphates de calcium, les oxydes de titane de zinc ou d'étain, le talc, le kaolin, des particules abrasives comprenant un coeur de matériau calcique, de préférence en carbonate de calcium et une écorce de produit idrophobe, de préférence un sel d'acide gras et plus préférentiellement encore un stéarate de Na ;
• un ou plusieurs composés fluorés correspondant à une concentration de l'ordre de 0,005 à 2 %, de préférence de 0,1 à 1 % en poids de fluor dans ladite composition, ces composés fluorés pouvant être en particulier les sels de l'acide monofluorophosphorique notamment ceux de sodium potassium, lithium, calcium, aluminium, et ammonium ou les fluorures de métaux alcalins, de sodium notamment ;
• éventuellement des agents tensio-actifs anioniques, non-ioniques, amphotères ou zwitterioniques, à raison d'environ 0,1 à 10 %, de préférence d'environ 1 à 5 % du poids de ladite composition ; on peut citer, à titre d'exemple :
  • des tensio-actifs anioniques comme les sels de sodium, de magnésium, d'ammonium, d'éthanolamine, des
    • alkyl sulfates en C₈-C₁₈ pouvant éventuellement contenir jusqu'à 10 motifs oxyéthylène et ou oxypropylène (laurylsulfate de sodium notamment)
    • alkyl sulfoacétates en C₈-C₁₈ (laurylsulfoacétate de sodium notamment)
    • alkyl sulfoacétates en C₈-C₁₈ (dioctylsulfosuccinate de sodium notamment)
    • alkyl sarcosinates en C₈-C₁₈ (laurylsarcosinate de sodium notamment)
    • alkyl phosphates en C₈-C₁₈ pouvant éventuellement contenir jusqu'à 10 motifs oxyéthylène et ou oxypropylène
    • alkyl éther carboxylates en C₈-C₁₈ contenant jusqu'à 10 motifs oxyéthylène et ou oxypropylène
    • les monoglycérides sulfatés...
  • des agents tensio-actifs non-ioniques comme les esters gras de sorbitan éventuellement polyéthoxylés, les acides gras éthoxylés, les esters de polyéthylèneglycol, ou encore les alcools gras polyéther,
  • agents tensio-actifs amphotères comme les bétaines, sulfobétaines
• éventuellement de l'eau à raison d'environ 0,1 à 50 %, de préférence environ 0,5 à 40 % du poids de ladite composition
• éventuellement des agents humectants, à raison d'environ 10 à 85 %, de préférence de 10 à 70 % du poids de ladite composition, humectants comme le glycérol, le sorbitol, les polyéthylèneglycols, le lactilol, le xylitol ...
• éventuellement des agents épaississants comme certaines silice utilisées à cet effet (TIXOSIL 43® commercialisée par RHONE-POULENC...) à raison de 5 à 15 % en poids et/ou des polymères utilisés seuls ou en association comme la gomme Xanthane, la gomme guar, les dérivés de la cellulose (Carboxyméthylcellulose, hydroxyéthylcellulose, hydroxypropylcellulose, hydroxypropylméthylcellulose....), des polyacrylates réticulés comme les CARBOPOL® distribués par GOODRICH, les alginates ou des carraghénannes, de la VISCARIN®, à raison de 0,1 à 5 % en poids.
• éventuellement des agents thérapeutiques bactéricides, anti-microbiens, anti-plaque, comme le citrate de zinc, les polyphosphates, les guanidines, les bis-biguanides ou autre composé organique thérapeutique cationique,
• éventuellement des agents arômatisants, (essence d'anis, de badiane, de menthe, de genièvre, cannelle, girofle, rose, ), des édulcorants, des colorants (chlorophylle), des conservateurs...

Without being limiting, we can give some details which define qualitatively and quantitatively the dental composition according to the invention, indicating that it contains:

• peroxygenated POS
  at a rate of 0.1 to 40% by weight,
  preferably from 0.1 to 10% by weight,
  and more preferably still on the order of 1 to 5% by weight;
• polishing abrasives at a rate of 5 to 40% by weight,
  preferably from 5 to 35% by weight, these abrasives possibly being in particular silica, precipitated calcium carbonate, magnesium carbonate, calcium phosphates, oxides of zinc or tin titanium, talc, kaolin , abrasive particles comprising a core of calcium material, preferably calcium carbonate and a shell of an idrophobic product, preferably a fatty acid salt and more preferably still a Na stearate;
• one or more fluorinated compounds corresponding to a concentration of the order of 0.005 to 2%, preferably 0.1 to 1% by weight of fluorine in said composition, these fluorinated compounds possibly being in particular the salts of monofluorophosphoric acid especially those of sodium potassium, lithium, calcium, aluminum, and ammonium or the fluorides of alkali metals, especially sodium;
• optionally anionic, nonionic, amphoteric or zwitterionic surfactants, at a rate of about 0.1 to 10%, preferably about 1 to 5% of the weight of said composition; we can cite, by way of example:
  • anionic surfactants such as sodium, magnesium, ammonium, ethanolamine salts,
    • C ₈ -C ₁₈ alkyl sulphates which may optionally contain up to 10 oxyethylene and or oxypropylene units (especially sodium lauryl sulphate)
    • C ₈ -C ₁₈ alkyl sulfoacetates (especially sodium lauryl sulfoacetate)
    • C ₈ -C ₁₈ alkyl sulfoacetates (especially sodium dioctylsulfosuccinate)
    • C ₈ -C ₁₈ alkyl sarcosinates (especially sodium laurylsarcosinate)
    • C ₈ -C ₁₈ alkyl phosphates which may optionally contain up to 10 oxyethylene and or oxypropylene units
    • C ₈ -C ₁₈ alkyl ether carboxylates containing up to 10 oxyethylene and or oxypropylene units
    • sulfated monoglycerides ...
  • nonionic surfactants such as optionally polyethoxylated sorbitan fatty esters, ethoxylated fatty acids, polyethylene glycol esters, or alternatively polyether fatty alcohols,
  • amphoteric surfactants such as betaines, sulfobetaines
• optionally water in an amount of about 0.1 to 50%, preferably about 0.5 to 40% of the weight of said composition
• optionally humectants, at a rate of approximately 10 to 85%, preferably from 10 to 70% of the weight of said composition, humectants such as glycerol, sorbitol, polyethylene glycols, lactilol, xylitol, etc.
• optionally thickening agents such as certain silica used for this purpose (TIXOSIL 43® marketed by RHONE-POULENC ...) at a rate of 5 to 15% by weight and / or polymers used alone or in combination such as Xanthan gum, gum guar, cellulose derivatives (Carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose ....), crosslinked polyacrylates such as CARBOPOL® distributed by GOODRICH, alginates or carrageenans, VISCARIN®, at a rate of 0.1 to 5% by weight.
• optionally bactericidal, anti-microbial, anti-plaque therapeutic agents, such as zinc citrate, polyphosphates, guanidines, bis-biguanides or other organic cationic therapeutic compound,
• possibly flavoring agents (essence of anise, star anise, mint, juniper, cinnamon, clove, rose,), sweeteners, colors (chlorophyll), preservatives ...

sous différentes formes (pâtes, gels, crèmes), préparées à l'aide des procédés conventionnels,

et sous divers conditionnements (e.g. mono ou bicompartiment).

The toothpaste composition which is the subject of the invention can be presented:

in different forms (pasta, gels, creams), prepared using conventional methods,

and under various packaging (eg mono or bi-compartment).

The present invention will be better understood using non-limiting examples which also highlight some of the benefits and variations of the invention. We present in these examples the preparation of POS precursors of peroxidized POSs according to the invention, the transformation by oxidation of these peroxidized POS precursors, and the evaluation of these in terms of storage stability and bleaching power.

EXAMPLES Example 1: preparation of a precursor - POS (B) of a peroxide POS according to the invention, this precursor being a polydimethylsiloxane with ends trimethylsilyles and carrying functional substituents of the -propyl-oxy-benzoic type

1.1. Synthesis of allyloxybenzoic acid

500 ml of distilled water, 51 of ethanol are charged into a 10 l reactor fitted with a condenser, a dropping funnel, a mechanical stirrer, a thermometer probe and under an argon sky. absolute and gradually 450.9 g of potash (8.02 moles) with vigorous stirring (240 rpm). Once the potassium has dissolved, 558.3 g of 4-hydroxy benzoic acid (4.04 moles) are charged. The reaction mass becomes cloudy and then becomes clear. The allyl bromide (489.0 g or 4.04 moles) is then poured in 2 hours at room temperature. After casting, the reaction medium is brought to 80 ° C for 17 hours.
After returning to ambient temperature, the reaction medium is neutralized by gradual addition over 1 h 30 min of 1 l of 36% hydrochloric acid (11 moles). The reaction medium becomes milky and it is filtered on a No. 4 frit under vacuum. A white filter cake is obtained which is washed with water (250 ml).
To carry out the purification of the allyloxybenzoic acid present in the filter cake, one proceeds by recrystallization. The filter cake, 5 l of absolute ethanol and 750 ml of distilled water are charged into the 10 l reactor. The reaction mass is brought to reflux (80 ° C.) and distilled water is gradually added until a single clear phase is obtained, namely 1.75 l of distilled water. The reaction mass is then transferred to a 10 l container which is cooled by ice. The medium is left to recrystallize for 16 h and then filtered through a No. 4 frit under vacuum. The cake is washed with distilled water (2 l used three times). Crystals are obtained which are dried under vacuum of 200 mmHg and at 70 ° C.
The yield is 35%.

1. 2. Protection of allyloxybenzoic acid by a trimethylsilyl group:

In a 250 ml three-necked flask fitted with a condenser, mechanical agitation, thermometer probe and under argon sky, 53.62 g of acid are introduced allyloxybenzoic acid prepared in 1.1. (0.3 mole) and poured in 1 hour 120.58 g hexamethyldisilazane (0.75 mole). The reaction medium is left in contact with 130 ° C for 24 hours. After returning to room temperature, protected allyloxybenzoic acid solution in solution in hexamethyldisilazane.

The protected product can be purified by vacuum distillation.

1.3. Hydrosilylation of protected allyloxybenzoic acid:

87.01 g of the protected acid solution are introduced into a 250 ml three-necked flask fitted with a condenser, a dropping funnel, a mechanical stirrer, a thermometer probe and under an argon sky. obtained in 1.2 (0.15 mole of protected acid) and 31.0 mg of platinum catalyst. The reaction medium is brought to 80 ° C. and stirred. Then, poured in 45 minutes on the reaction medium 35.03 g of oil of structure A (0.13 mole of SiH function). The reaction medium is then left in contact for 16 hours. During this contact time, 7.5 mg of PtCl ₂ (PhCN) _{2 are added} .
At 85 ° C., 2% by mass of carbon black is added which is left in contact for 16 hours. After returning to ambient temperature, the reaction medium is filtered on a cardboard filter under pressure and then the reaction mass is returned to a single-color flask fitted with a magnetic bar. The product is isolated by devolatilization at 120 ° C under vacuum of 1 mmHg.
The product thus isolated is deprotected by hydrolysis with distilled water (200 ml) which is poured onto the product to be deprotected in 1 hour 15 minutes and heating to 90 ° C. for 16 hours. The medium becomes whitish. The water is removed at 110 ° C. under a vacuum of 2 mmHg for 4 h 15 min. 58.40 g of hydrosilylated oil of structure B are then obtained.

1.4. Purification of a silicone oil B with benzoic acid functions :

We start from a pure oil at 92% by mass with 8% by mass consisting of oligomers ungrafted from ungrafted allyloxybenzoic acid or acid isomers allyloxybenzoic. Among the different purification techniques several are possible. The method used here is fractional precipitation. It is dissolve the grafted oil obtained in 1.3 in a hot alcohol. This alcohol can be more particularly methanol. Then the polymer is precipitated by addition water of basic pH. The operation is repeated another time. The third operation consists in hot solubilizing the silicone polymer in methanol and then adding water at acidic pH. The polymer thus purified is heated to 115 ° C. under a vacuum of 20 mmHg to remove residual water or alcohol. The product is finally placed in the oven at 100 ° C. under atmospheric pressure. A polymer of purity greater than 95% is obtained in weight.

Example 2: preparation of a precursor - POS (C) of a peroxide POS according to the invention, this precursor being a polydimethylsiloxane with ends trimethylsilyl and carrying functional substituents of the -propylanhydride type succinic

Synthesis of silicone oil C with succinic anhydride units :

In a 500 ml three-necked flask fitted with mechanical agitation, a condenser, a pouring funnel, temperature probe and under argon sweep, we introduce 119.53 g of pure succinic allylanhydride with more than 99 mol% (0.85 mol) and 44.2 mg of Karstedt platinum at 10% by mass of platinum. The reaction medium is brought to 90 ° C with stirring then 175.53 g of oil of structure A (0.66 mole of SiH function) in 1 hour 25 minutes. The reaction medium is left in contact at 90 ° C under stirring for 4 hours. The reaction medium is then treated with 2% by weight of carbon black at 70 ° C for 4 hours. After returning to room temperature, filters the reaction medium on cardboard under nitrogen pressure. After placing the middle reaction in a single-color flask fitted with a magnetic bar, the polymer is isolated silicone grafted by devolatilizing the excess oligomer by heating to 180 ° C. under vacuum 2 mmHg. A silicone oil of structure C and of purity equal to 94% is obtained in weight.

To purify this product to more than 99% by weight of purity, the product was devolatilized using a vacuum diffusion pump of 10 ^-3 mmHg by heating the polymer from 120 to 160 ° C for 6 hours. This gives a grafted silicone propylanhydride succinic polymer of purity greater than 99% by weight. Infrared analysis shows that the anhydride is not opened during the treatments described in the examples.

Example 3: preparation of a precursor - POS (E) of a peroxide POS according to the invention, this precursor being a polydimethylsiloxane with ends trimethylsilyl and carrying functional substituents of the -propyl-succinimide type benzoic

3.1. Preparation of silicone with amine function by coequilibration :

50 g of aminopropyldimethoxymethylsilane (0.3 mole) are introduced into a three-necked flask provided with a devolatilization system, a mechanical stirrer, a dropping funnel, a temperature probe and under an argon sky and a quantity of 27.6 g of water (1.5 mole) is added over 1 hour. It is brought to 110 ° C. and devolatilized under 11 mmHg in order to collect the quantity of methanol of 19.2 g.
After returning to temperature and having replaced the distillation system with a refrigerant, in addition to 35.1 g of hydrolyzed silane previously obtained, 30.5 g of octamethyltetrasiloxane (0.1 mol or 10% excess) are introduced. 34.3 g of a short silicone oil with 6 silicones of formula M ₂ D ₄ and 5.3 g of potassium siliconate at 15% by weight of potassium hydroxide (80 ppm). After heating at 130 ° C. for 6 hours under nitrogen stripping, the reaction mixture is neutralized by the addition of 12.3 g of a solution of silicon ester of phosphoric acid at 9% by mass of phosphoric acid. Following neutralization, the medium is left in contact for 30 minutes at 80 ° C. and then devolatilized under 2 mmHg at 170 ° C. 113.5 g of silicone oil of structure D are obtained.

3.2. Formation of a silicone E with acid and imide functions

In a three-necked flask fitted with a refrigerant, a mechanical stirrer, a light bulb, thermometer probe, Dien Stark system and under sky of argon, 28.8 g of trimellic anhydride (0.15 mol) are charged, and 75 g of toluene and 50.0 g of silicone oil with an amine function of structure D (0.15) are poured in over 1 hour mole of amine function). The reaction mixture is left in contact at temperature ambient for 1 hour then the reaction mixture is brought to reflux for 5 hours over time we follow the elimination of water. After return to temperature ambient, the reaction mixture is filtered on cardboard and under pressure. After having placed the latter in a single-colored balloon fitted with a magnetic bar, we devolatilize the solvent by heating to 110 ° C under vacuum of 10 mmHg. We obtain a polymer of structure E pure at 95% by weight.

EXAMPLE 5: OBTAINING A PEROXIDE POS IN WHICH THE FPO FUNCTIONS (-OO-) OF THE SUBSTITUTES E ARE INCLUDED IN PERACID CARBOXYL REMAINS

FROM THE PRECURSOR POS AS EXAMPLE 2 (REMAINING ANHYDRIDES REMAINING) 5.1. Trial

• peser 250 mg d'huile silicone C de l'exemple 2 soit 0,615 mmole de fonctions anhydrides (4 fonctions par polymère)
• ajouter 0,5 ml d'acétate d'éthyle (AcOEt),
• peser 45 mg d'eau oxygénée à 70 % soit 0,926 mmole (excès 1,5 équivalent par rapport à la stochiométrie qui est de 1 H₂O₂ par anhydride).
• introduire 1 goutte de KOH (1N)
• ajouter un petit barreau magnétique
• agiter à température ambiante pendant 1 heure.

In a weighing tube:

• weigh 250 mg of silicone oil C from Example 2, ie 0.615 mmol of anhydride functions (4 functions per polymer)
• add 0.5 ml of ethyl acetate (AcOEt),
• weigh 45 mg of hydrogen peroxide at 70% or 0.926 mmol (excess 1.5 equivalent relative to the stochiometry which is 1 H ₂ O ₂ per anhydride).
• introduce 1 drop of KOH (1N)
• add a small magnetic bar
• stir at room temperature for 1 hour.

5.2. Treatment

• add 3 ml AcOET
• transfer to a small 50 ml separating funnel
• add 3 ml of deionized water to 100 g / l of ammonium sulphate
• stir, allow to settle, remove the lower aqueous phase
• repeat the operation 2 more times
• recover the organic phase in a 50 ml beaker,
• add 1 g of anhydrous MgSO ₄
• transfer to a tared 50 ml flask, rinse the ampoule 2 times and MgSO4 with 1 ml of ACOEt
• dry draw with Rotavapor, bath at 35 ° maximum
• draw a few minutes under vacuum pump, cold (room temperature)
• weigh the product obtained

5.3. Peroxide determination in peroxidized silicone oil

5.3.1. Mode opératoire
En erlen de 50 ml :

• peser environ 250 mg d'huile peroxydée
• ajouter :
  • 20 ml de mélange ACIDE ACETIQUE / H₂O 80/20 et dissoudre
  • ou mieux 20 ml d'acide acétique pur, dissoudre, puis ajouter un peu d'eau
• ajouter 1 spatule (1g) de NaHCO₃ (inertage par CO₂)
• ajouter 1 spatule (1g) d'iodure de potassium
• boucher et mettre à l'obscurité 20 minutes minimum.

Transférer dans un bécher de 150 ml (forme haute) :

• rincer avec 50 ml d'eau distillée
• ajouter de l'acétone (maintient de la solubilité et antimousse)
• ajouter un barreau magnétique et mettre en place, dosage de l'iode libérée par une solution de THIOSULFATE DE SODIUM 0,1 N

5.3.2. Calculs
Nbre mmoles H₂O₂ = Vml x CO3 x CO2 / COO x CO1
% poids H₂O₂ = Nbre millimoles dosées x 34 / 1000
1 équivalent H₂O₂ = 1 équivalent R-CO-O-OH

5.3.3. Expression des résultats : % poids en équivalent H₂O₂
Etant donné que le précurseur -POS (huile - C -) préparé dans l'exemple 2 comprend les substituants E porteurs chacun d'un anhydride, et que l'on suppose que la réaction est totale (rendement d'oxydation = 100 %), alors pour une mole d'huile (- C -), on fait réagir 4 moles d'H₂O₂, soit en % en poids : 1 mole huile (- C -) = 1628 g, pour 4 moles H₂O₂ = 136 g, soit 8,35 % poids d'H₂O₂.

5.3.4. Résultat La teneur en peracide de l'huile C oxydée est de 6,2 %, soit une oxydation de 6,2 / 8,35 x 100 = 74 %.

Device: METROHM Dosimat 665

5.3.1. Procedure
In 50 ml Erlenmeyer flask:

• weigh approximately 250 mg of peroxidized oil
• add :
  • 20 ml of ACETIC ACID / H ₂ O 80/20 mixture and dissolve
  • or better 20 ml of pure acetic acid, dissolve, then add a little water
• add 1 spatula (1g) of NaHCO ₃ (inerting with CO ₂ )
• add 1 spatula (1g) of potassium iodide
• stopper and put in the dark for at least 20 minutes.

Transfer to a 150 ml beaker (tall form):

• rinse with 50 ml of distilled water
• add acetone (maintains solubility and defoamer)
• add a magnetic bar and put in place, assay of the iodine released by a solution of THIOSULFATE OF SODIUM 0.1 N

5.3.2. calculations
No. mmoles H ₂ O ₂ = Vml x CO3 x CO2 / COO x CO1
% weight H ₂ O ₂ = No. of millimoles dosed x 34/1000
1 equivalent H ₂ O ₂ = 1 equivalent R-CO-O-OH

5.3.3. Expression of results:% weight in H ₂ O ₂ equivalent
Since the precursor -POS (oil - C -) prepared in Example 2 comprises the substituents E each carrying an anhydride, and it is assumed that the reaction is complete (oxidation yield = 100%) , then for one mole of oil (- C -), 4 moles of H ₂ O ₂ are reacted, that is in% by weight: 1 mole oil (- C -) = 1628 g, for 4 moles H ₂ O ₂ = 136 g, or 8.35% by weight of H ₂ O ₂ .

5.3.4. Result The peracid content of oxidized oil C is 6.2%, i.e. an oxidation of 6.2 / 8.35 x 100 = 74%.

EXAMPLE 6 OBTAINING A PEROXIDE POS IN WHICH THE FPO FUNCTIONS (-OO-) OF THE SUBSTITUTES ARE INCLUDED IN PERACID CARBOXYLIC RESIDUES

FROM THE PRECURSOR POS AS EXAMPLE 2 (REMAINING ANHYDRIDES REMAINING)

• 15 g d'huile C de l'exemple 2 (36,9 mmoles anhydride)
• 30 g d'acétate d'éthyle
• 2,7 g d'eau oxygénée 0 70 % (55,6 mmoles (x 1,5))
• 0,6 ml de KOH N (0,6 mmole)

Mettre un barreau magnétique et agiter. L'exothermie est immédiate, la température atteint 31°C.
Placer un cristallisoir d'eau froide pour ramener à température ambiante
Maintenir 1 heure
Transvaser en ampoule à décanter de 100 ml, rincer 2 fois le ballon par 10 ml d'AcOEt
Procéder à 8 lavages par 20 ml d'eau permutée à 100 g/l de sulfate d'ammo : la disparition de l'eau oxygénée dans les phases aqueuses est suivie par papier indicateur des peroxydes.
Sécher sur MgSO₄ anhydre
Filtrer sur verre fritté
Transvaser dans un ballon de 100 ml, rincer l'ampoule et le fritté
Tirer à sec au rotovapor, bain à 35° maxi.
Sécher sous vide pompe pendant 3 heures à température ambiante.
Poids obtenu : 15,4 g
Teneur en peracides : 5,46 % (exprimé en H₂O₂)
Oxydation : 65 %In 100 ml flask, load:

• 15 g of oil C from Example 2 (36.9 mmol anhydride)
• 30 g ethyl acetate
• 2.7 g of hydrogen peroxide 0 70% (55.6 mmol (x 1.5))
• 0.6 ml KOH N (0.6 mmol)

Put on a magnetic bar and shake. The exotherm is immediate, the temperature reaches 31 ° C.
Place a crystallizer of cold water to bring it to room temperature
Maintain 1 hour
Transfer to 100 ml separating funnel, rinse the flask twice with 10 ml of AcOEt
Proceed to 8 washes with 20 ml of water permuted to 100 g / l of ammonium sulphate: the disappearance of hydrogen peroxide in the aqueous phases is followed by indicator paper for peroxides.
Dry over anhydrous MgSO ₄
Filter on sintered glass
Transfer to a 100 ml flask, rinse the vial and the frit
Draw dry on rotovapor, bath at 35 ° max.
Dry under vacuum pump for 3 hours at room temperature.
Weight obtained: 15.4 g
Peracid content: 5.46% (expressed as H ₂ O ₂ )
Oxidation: 65%

EXAMPLE 7 STUDY OF THE STABILITY OF STORAGE OF POS PEROXIDES ACCORDING TO THE INVENTION

7.1. Stockage à 5° C de 0 à 30 jours
Les résultats sont donnés par le tableau 1 ci-dessous. Durée (j) % Peracides % oxydation 0 5,72 100,0 2 5,48 95,8 6 5,08 88,8 13 3,82 66,8 22 2,90 50,7 30 1,70 30,0

7.2. Stockage à 5 °C, 0, 11 et 22 jours
Les résultats sont donnés par le tableau 2 ci-dessous Durée jours % peracides 5° C % oxydation 5°C 0 5,46 100,0 11 4,24 74,1 22 2,85 49,8

The POS used is prepared according to the methodology given in Example 6.
The product is stored dried at 5 ° C and 25 ° C.
Samples are taken over time and dose the peroxides as described above in 5.3.

7.1. Storage at 5 ° C from 0 to 30 days
The results are given in Table 1 below. Duration (d) % Peracids % oxidation 0 5.72 100.0 2 5.48 95.8 6 5.08 88.8 13 3.82 66.8 22 2.90 50.7 30 1.70 30.0

7.2. Storage at 5 ° C, 0, 11 and 22 days
The results are given in Table 2 below Duration days % peracids 5 ° C % oxidation 5 ° C 0 5.46 100.0 11 4.24 74.1 22 2.85 49.8

EXAMPLE 8 OBTAINING A PEROXIDE POS IN WHICH THE FPO FUNCTIONS (-OO-) OF THE SUBSTITUTES ARE INCLUDED IN PERACID CARBOXYLIC RESIDUES

FROM THE PRECURSOR POS AS EXAMPLE 2 (REMAINING ANHYDRIDES REMAINING)

Example 5 is reproduced with the difference that no KOH is used.

Results:

• H ₂ O ₂ equivalent content = 0.59%
• oxidation: 7%

EXAMPLE 9 OBTAINING A PEROXIDE POS IN WHICH THE FPO FUNCTIONS (-OO-) OF THE SUBSTITUTES E ARE INCLUDED IN PERACID CARBOXYL REMAINS

FROM THE PRECURSOR POS AS EXAMPLE 2 (REMAINING ANHYDRIDES REMAINING)

Example 6 is reproduced with the difference that the drop of KOH is replaced by a drop of H ₃ PO ₄ (85% in water).

Results :

• H ₂ O ₂ equivalent content = 1.03%
• oxidation: 12%

EXAMPLE 10: OBTAINING A PEROXIDE POS IN WHICH THE FPO FUNCTIONS (-OO-) OF THE SUBSTITUTES E ARE INCLUDED IN PERACID CARBOXYLIC RESIDUES

FROM THE POS PRECURSOR AS IN EXAMPLE 1 (PENDANT BENZOIC REMAINS)

10.1 Test In weighing tube:

• weigh 250 mg of silicone oil B from Example 1, i.e. 0.578 mmol of acid functions (4 functions per polymer)
• add 0.5 ml of ethyl acetate (AcOEt),
• weigh 84 mg of 70% hydrogen peroxide, ie 1.729 mmol (excess 3 equivalents compared to the stochiometry which is 1 H ₂ O ₂ per acid).
• 1 drop H ₂ SO ₄ (95% in water)
• add a small magnetic bar
• stir at room temperature for 2 hours, in the presence of an excess anhydrous MgSO4 (> 100 mg).

10.2. Treatment

• add 3 ml AcOET
• transfer to a small 50 ml separating funnel
• add 3 ml of deionized water to 100 g / l of ammonium sulphate
• stir, allow to settle, remove the lower aqueous phase
• repeat the operation 2 more times
• recover the organic phase in a 50 ml beaker,
• add 1 g of anhydrous MgSO ₄
• transfer to a tared 50 ml flask, rinse the ampoule 2 times and MgSO4 with 1 ml of ACOEt
• dry draw with Rotavapor, bath at 35 ° maximum
• draw a few minutes under vacuum pump, cold (room temperature)
• weigh the product obtained

10.3 Result

• Peracid content: 0.66%
• oxidation: 9%

EXAMPLE 11: EVALUATION OF THE WHITENING POWER OF THE POS PEROXIDE OF EXAMPLE 6 11. 1 Method under development for determining the whitening power on hydroxyapatite PAH powder

11. 1. 1. Principle

• Measurement of the whitening power of oxidizing compounds, on a hydroxyapatite PAH powder, previously fouled with a hot tea solution.
• Whitening power quantified by colorimetric measurements performed on the Minolta CR-241 device.

A - Petits ustensiles

• Papier filtre, « filtration rapide » n°41 de Whatman pour la filtration de la solution de thé et pour la récupération de la poudre encrassée
• Papier filtre.GF/C diamètre de 47 mm de Whatman utilisé pour la récupération de la poudre blanchie
• Büchner (diamètre de 100 ou 160 mm), fiole à vide de 2 L, pompe à vide ou trompe à eau avec manomètre différentiel, joints en caoutchouc
• Pots en polystyrène cristal (transparent), capacité de - 40 ml

B - Appareils

• Colorimètre Minolta CR-241
• Agitateur va-et-vient Promax 2020
• Etuve (50 à 100 ° C)

C - Produits

• Eau désionisée
• Thé Lipton Yellow, qualité n°1
• Poudre d'hydroxyapatite HAP BIO-RAD
• Solution ou oxydante

11.1.2.Appareillage

A - Small utensils

• Filter paper, “rapid filtration” n ° 41 from Whatman for the filtration of the tea solution and for the recovery of dirty powder
• Filter paper.GF/C diameter 47 mm from Whatman used for the recovery of bleached powder
• Büchner (diameter 100 or 160 mm), 2 L vacuum flask, vacuum pump or water pump with differential pressure gauge, rubber seals
• Crystal polystyrene jars (transparent), capacity of - 40 ml

B - Devices

• Minolta CR-241 colorimeter
• Promax 2020 back and forth shaker
• Oven (50 to 100 ° C)

C - Products

• Deionized water
• Lipton Yellow tea, quality n ° 1
• BIO-RAD HAP hydroxyapatite powder
• Solution or oxidant

A - Encrassement de la poudre HAP

a - Mesure de la blancheur initiale de la poudre
Une mesure de la blancheur initiale de la poudre HAP est effectuée. Elle s'effectue sur l'appareil Minolta CR-241. Trois mesures sont faites pour obtenir une valeur moyenne de Lo, ao, bo.

b -Décoction du thé, filtration
Dans un bêcher de 1 000 ml, 500 ml d'eau désionisée et 10 sachets de thé découpés sont introduits (C= ∼ 40g/l) et portés à ∼ 80°C sous agitation mécanique (200 tr/min) pendant 90 minutes.
L'agitation et la puissance de chauffe sont arrêtés. Une fois le milieu refroidi à ∼ 40°C (durée nécessaire = ∼ 90 min), il est filtré sous vide.
Le filtrat (= solution encrassante de thé) est récupéré. Son volume est réajusté à 500 ml avec de l'eau désionisée.

c - L'encrassement
7,5 g de poudre HAP sont introduits dans la solution de thé.
L'ensemble est à nouveau porté à ∼ 80°C, sous agitation pendant 45 minutes.
Le chauffage et l'agitation sont arrêtés, le milieu refroidit à l'air ambiant (jusqu'à ~ 40°C) avant d'être filtré sous vide.
La poudre est lavée avec trois fois 20 ml d'eau désionisée chaude jusqu'à ce que le filtrat soit incolore.
Le filtre et la poudre sont placés à l'étuve [T= 50-100°C] jusqu'à évaporation complète de l'eau.
La poudre récupérée sous forme d'agglomérats est broyée à l'aide d'un mortier et d'un pilon.
Sa nouvelle blancheur est mesurée (Ls, as, bs) au Minolta CR-241.

B - Blanchiment de la poudre HA P encrassée
6.5 g de solution oxydante (contenant l'équivalent de 0.3 % en H₂O₂) et 50 mg de poudre HAP encrassée sont transvasés dans un flacon en polystyrène cristal de contenance - 40 ml.
Le tout est placé sur l'agitateur va-et-vient PROMAX 2020 pendant le temps souhaité (15 min, 30 min, 1h, 2h, ...) à raison de 250 allers-retours.
Le milieu est ensuite dilué par addition de 20 ml d'éthanol avant d'être filtré.
La poudre est lavée avec trois fois 30 ml d'éthanol.
L'ensemble filtre + poudre blanchie est séché à l'air libre sous hotte.
La nouvelle blancheur de la poudre blanchie peut être mesurée (Lc), et le pouvoir blanchissant de la solution oxydante peut être calculé.

11.1.3. Procedure

A - Contamination of the PAH powder

a - Measurement of the initial whiteness of the powder
A measurement of the initial whiteness of the PAH powder is carried out. It is performed on the Minolta CR-241 device. Three measurements are made to obtain an average value of Lo, ao, bo.

b - Tea decoction, filtration
In a 1000 ml beaker, 500 ml of deionized water and 10 cut tea bags are introduced (C = ∼ 40g / l) and brought to ∼ 80 ° C with mechanical stirring (200 rpm) for 90 minutes.
Stirring and heating power are stopped. Once the medium has cooled down to ∼ 40 ° C (required time = ∼ 90 min), it is filtered under vacuum.
The filtrate (= fouling tea solution) is collected. Its volume is readjusted to 500 ml with deionized water.

c - Fouling
7.5 g of PAH powder are introduced into the tea solution.
The whole is again brought to ∼ 80 ° C., with stirring for 45 minutes.
Heating and stirring are stopped, the medium cools with ambient air (up to ~ 40 ° C) before being filtered under vacuum.
The powder is washed with three times 20 ml of hot deionized water until the filtrate is colorless.
The filter and the powder are placed in an oven [T = 50-100 ° C] until the water has completely evaporated.
The powder recovered in the form of agglomerates is ground using a mortar and pestle.
Its new whiteness is measured (Ls, as, bs) with the Minolta CR-241.

B - Bleaching of dirty HA P powder
6.5 g of oxidizing solution (containing the equivalent of 0.3% of H ₂ O ₂ ) and 50 mg of contaminated PAH powder are transferred to a crystal polystyrene bottle of capacity - 40 ml.
The whole is placed on the PROMAX 2020 back-and-forth agitator for the desired time (15 min, 30 min, 1 hour, 2 hours, etc.) at the rate of 250 round trips.
The medium is then diluted by adding 20 ml of ethanol before being filtered.
The powder is washed with three times 30 ml of ethanol.
The whole filter + bleached powder is dried in the open air in a hood.
The new whiteness of the bleached powder can be measured (Lc), and the whitening power of the oxidizing solution can be calculated.

¤ Pouvoir blanchissant : Pb = Lc - Ls Lo - Ls x 100

11.1.4 Calculations
The bleaching power of the oxidizing compound is calculated from the value L given by the colorimeter, and obtained after the various treatments of the PAH powder.
L * represents the clarity of the sample, its values range between 0 and 100.
We thus define the different values:

• Lo, initial clarity before fouling.
• Ls, clarity after fouling.
• Lc, clarity after bleaching.

The whitening power is calculated as follows:

¤ Whitening power: Pb = Lc - Ls Lo - Ls x 100

11.2 Measurement of the whiteness Lc obtained in the test described in 11.1 above, with the peroxidized POS of Example 6

11.2.1. The bleaching of the PAH powder according to point 11.1.3 B above is carried out as follows:
6.5 g of oxidizing preparation containing 300 mg of peroxidized POS according to Example 6 dispersed in 6.2 g of inverted water by manual stirring.
and 50 mg of dirty PAH powder are transferred to a 40 mg crystal polystyrene bottle.
Then proceed as indicated in point 11.1.3. B.

11.2.2 Results Time (min) LC with water indicator Pb Lc with peroxidized POS Pb 0 50 0 50 0 15 49 0 69 45 60 49 0 69 45 120 49 0 70 48

Claims (12)

1. Polyorganosiloxanes (POSs) comprising siloxane units of following formula (I): RaEbGcSiO 4 - (a+b+c)2

   in which

   a + b + c = 0 to 3

   a, b, c = 0 to 3

   R corresponds to one or more identical or different radicals, R being chosen from monovalent hydrocarbonaceous groups, preferably from linear, branched and/or cyclic alkyls and/or aryls, and more preferably still from linear or branched C₁-C₄ alkyls and phenyl, xylyl and tolyl groups;

   E corresponds to one or more monovalent functional substituents, which are identical to or different from one another, chosen from (cyclo)aliphatic and/or aromatic hydrocarbonaceous groups and/or heterocyclic groups and carrying one or more acyl peroxide functional groups Fpo of formula

   

   with X corresponding to H, a halogen, preferably chlorine, or to a cation which makes it possible to form a salt with the acyl peroxide anion and which is preferably chosen from the elements from columns Ia and IIa of the Periodic Table, and each optionally comprising one or more Fpo-stabilizing functional groups Fstab which are identical to or different from one another and are chosen from functional groups capable of bonding via weak bonds with the Fpo functional groups;

   G corresponds to one or more functional substituents, identical to or different from one another, each comprising one or more Fpo-stabilizing functional groups Fstab which are identical to or different from one another and are chosen from functional groups capable of bonding via weak bonds with the Fpo functional groups;

   with the conditions according to which:

   (i). the concentration of [Fpo] functional groups, expressed by the ratio Fpo number Total number of silicon atoms in the POS is defined as follows:

   Δ 0 < [Fpo]

   Δ preferably   0.01 ≤ [Fpo] ≤ 1.0

   Δ and more preferably still   0.1 ≤ [Fpo] ≤ 0.6,

   (ii). the concentration as mol% of T siloxane units (a + b + c = 1) and/or Q siloxane units (a + b + c = 0) is defined as follows:

   Δ 0 ≤ [T and/or Q] ≤ 20

   Δ preferably   0 ≤ [T and/or Q] ≤ 10

   Δ and more preferably still   0 ≤ [T and/or Q] ≤ 8.
2. Polyorganosiloxanes according to claim 1, characterized in that, in the G substituent or substituents of the formula (I), the Fstabs correspond to functional groups which can generate weak bonds (hydrogen bonds) with Fpo and which are selected from the group consisting of:

   functional units comprising nitrogen and/or oxygen and/or fluorine and/or sulphur and/or phosphorus; carboxylic, carboxylate, amide, imide, sulphonamide, hydroxyl, alkoxy, amine or organofluorinated units being preferred;

   cationic units, preferably those comprising one or more quaternary ammoniums;

   chelating units comprising one or more ether functional groups and/or one or more amine functional groups, and/or phosphonate and/or sulphonate chelating units.
3. Polyorganosiloxanes according to either one of claims 1 and 2, characterized in that they correspond to the formula (II) given below:

   

   in which:

   R¹ and R³ independently represent a hydrogen, a hydroxyl or a monovalent residue corresponding to the same definition as that given for R above;

   R² independently represents hydrogen, a hydroxyl or a monovalent residue corresponding to the same definition as that given for R above;

      2 ≤ m + n + o ≤ 300

   preferably   3 ≤ m + n + o ≤ 50

   and more preferably still   5 ≤ m + n + o ≤ 20

      0 ≤ m ≤ 200

   preferably   1 ≤ m ≤ 100

   and more preferably still   1 ≤ m ≤ 10

      0 ≤ n ≤ 50

   preferably   1 ≤ n ≤ 10

   and more preferably still   2 ≤ n ≤ 4

      0 ≤ o ≤ 50

   preferably   1 ≤ o ≤ 10

   and more preferably still   2 ≤ o ≤ 4.
4. Polyorganosiloxanes according to claim 4,
   characterized in that:

   Δ R¹ and R³ = C₁-C₃ alkyl, preferably -CH₃

   Δ R² = C₁-C₃ alkyl, preferably -CH₃

   Δ the functional substituent or substituents E simultaneously comprise Fpo and Fstab functional groups.
5. Polyorganosiloxanes according to any one of the preceding claims, characterized in that E comprises, an Fpo percarboxylic acid functional group and an Fstab carboxylic acid functional group.
6. Process for the preparation of the POSs according to any one of claims 1 to 5, characterized in that it consists essentially in oxidizing polysiloxane precursors of the said POSs using at least one oxidizing agent preferably chosen from the group consisting of:
   H₂O₂, O₂, O₃ and their mixtures,
      these polysiloxane precursors being distinguished from the polyorganosiloxanes (POSs) in that they comprise one or more F' po functional groups which are Fpo precursors and are composed:
   of carboxyl residues:

   

   with X' corresponding to the same definition as that given for X in claim 1; and/or of acid anhydride residues:

   
7. Process according to claim 6, characterized in that the polyorganosiloxane precursors selected:

   carry F'po anhydride functional groups, the oxidation being carried out using H₂O₂ in the presence of a catalyst of strong base type, preferably potassium hydroxide,

   and/or carry F'po carboxylic functional groups, preferably benzoyl groups, the oxidation being carried out using H₂O₂ in the presence of a catalyst of strong acid type.
8. Process according to claim 7, characterized in that the polyorganosiloxane precursors carry F'po succinic anhydride functional groups connected to the silicon atoms via a -(CH₂)₃- linking unit.
9. Process according to any one of claims 6 to 8, characterized in that use is made of POS precursors with a molar purity ≥ 90%, preferably ≥ 95%.
10. Use of the polyorganosiloxanes (POSs) forming the subject-matter of any one of claims 1 to 8 or obtained according to the process forming the subject-matter of any one of claims 9 to 12 in a dental composition, as agent for bleaching the teeth.
11. Dental composition, in particular a dentifrice, characterized in that it comprises at least one polyorganosiloxane (POS) forming the subject-matter of any one of claims 1 to 5 or obtained according to the process forming the subject-matter of any one of claims 6 to 9 as bleaching agent.
12. Dental composition according to claim 11, characterized in that it comprises:

    from 0.1 to 40% by weight of at least one polyorganosiloxane (POS)

    from 5 to 40% by weight of at least one polishing agent

    and from 0.005 to 2% by weight of at least one fluorinated compound.