CA2208367A1

CA2208367A1 - Cleansing compositions

Info

Publication number: CA2208367A1
Application number: CA002208367A
Authority: CA
Inventors: Iain Allan Hughes; Elizabeth Mary Ryan; Christopher David White
Original assignee: Individual
Current assignee: Procter and Gamble Co
Priority date: 1994-12-22
Filing date: 1995-11-21
Publication date: 1996-06-27
Also published as: BR9510282A; TR199501649A2; EP0799294A4; NZ297292A; MX9704723A; EP0799294A1; SK82597A3; KR100209999B1; GB9425932D0; CZ190697A3; CN1170427A; PL320868A1; AU709629B2; RU97112391A; HUT77704A; JPH10510833A; WO1996019554A1; TR199501649A3; AU4241996A

Abstract

A denture cleansing composition comprising an inorganic persalt bleaching agent, an effervescence generator and an aminoalkylsilicone. The composition provides improved antiplaque, cleansing and antibacterial activity together with excellent physical and in-use performance characteristics.

Description

WO 96/19554 PCT/IJS9~ 142 CLEANSING COMPOSITIONS

TECHNICAL FIELD

The present invention relates to cle~n~in~ compositions and especially to compositions for use in cle~n~ing dentures and the like. In particular, the invention relates to denture cle~n~in~ compositions having enhanced antiplaque activity together with excellent denture cle~n~ing performance, appearance, physical and dissolution characteristics, anti-bacterial efficacy and in-use performance characteristics.

BACKGROUND

Effervescent tablets and powders for cle~n~in~ dentures and the like are well known in the art. The aim of a denture cleanser product is to clean the denture as fully and as quickly as possible and especially to remove the accllmlll~tion of plaque, mucil~inous and bacterial deposits which collect while the denture is being worn. To wear a denture which has not been completely clP~n~-l of plaque and bacterial deposits is not only unhygenic but can also within a short space of time result in a detrimental effect on the mucous membrane. Moreover bacterial deposits can lead to so-called bacterial corrosion of the plastics material used to produce the denture with consequent color-change and malodor-formation.

It is known to include silicones in dentifrice compositions, allegedly to coat the teeth and prevent cavities and st~inin~. For in~t~nce, GB-A-689,679 discloses a mouthwash cont~ining an organopolysiloxane for preventing adhesion of, or for removing tars, stains, tartar and food particles from the teeth.

US-A-2,806,814 discloses dental preparations including, in combination, a higher aliphatic acyl amide of an amino carboxylic acid compound as an active and a silicone compound. The patent notes that silicone compounds have been proposed for prevention of adhesion or to facilitate the removal of tars, stains, tartar and the like from teeth. The silicone compound is said to act as a synergist in improving the antibacterial and W O96/19554 PCTrUS95115142 acid inhibiting activity of the active ingredient. Dimethyl polysiloxanes are said to be particularly effective.

US-A-3624120 discloses quaternary ammonium salts of cyclic siloxane polymers for use as cationic surfactants, bactericides and as anticariogenic agents.

Dentures of course are generally made of a plastics material such as acrylic and the problem of preventing plaque accllm~ tion or oi removing plaque from dentures is therefore fi-nrl~mentally different from the problem of plaque prevention and removal from dental enamal.

Accordingly, the present invention provides a denture cleanser having improved efficacy on plaque, mucilaginous and bacterial deposils and which at the same time provides excellent denture cle~ncin~ performance, appearance, physical characteristics, dissolution and in-use performance characteristics .

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a denture cle~ncing composition comprising an inorganic persalt bleaching agent, an effervescence generator and an aminoalkylsilicone as antiplaque agent.
The present invention also relates to the use of the defined aminoalkylsilicone as antiplaque agent in denture cle~n~ing compositions All percentages and ratios herein are by weight of total composition, unless otherwise indicated.

The cle~ncin~ compositions of the invention thus comprise three essential components, a bleaching agent, an aminoalkylsilicone and an effervescent base composition. Each of these will be discussed in turn.

The bleaching agent takes the form of an inorganic persalt and c an be selected from any of the well-known bleaching agents known for use in denture cleansers such as the alkali metal and ammonium persulfates, perborates, percarbonates and perphosphates and the alkali metal and ~lk~line earth metal peroxides. Examples of suitable bleaching agents include potassium, ammonium, sodium and lithium persulfates and perborate mono- and tetrahydrates, sodium pyrophosphate peroxyhydrate and magnesium, calcium, strontium and zinc peroxides. Of these, however, the alkali metal persulfates, perborates and mixtures thereof are prefered for use herein, highly preferred being the alkali metal perborates. Tntlee~l, it is a feature of the invention that the tablet compositions herein will provide excellent antimicrobial activity even in the absence of alkali metal persulfates.

The amount of bleaching agent in the total composition is generally from about S to about 70% preferably from about 10% to about 50%. In compositions comprising a mixture of alkali metal pers~llf~tes and perborates, the overall persulfate:perborate ratio is suitably from about 5:1 to about 1:5, more especially from about 2:1 to about 1:2.

The compositions herein also contain an aminoalkylsilicone antiplaque agent. In general terms, the aminoalkylsilicone is selected from noncyclic, hydrophobic amino~lkysilicones having a formula comprising two basic units:

1) (Rl)m(R)nsi~(4-m-n)l2 wherein m+n is 1, 2 or 3; n is 1, 2 or 3;
m is 0,1,2; and 2) (Rl)a(R2)bSiO(4 a b)/2 wherein a+b is 1, 2, or 3, and a and b are integers, wherein Rl and R2 are independently selected from H ,alkyl and alkenyl of about 1 to about 10 carbons optionally substituted with fluoro or cyano groups, hydroxy, alkoxy, and acetoxy, for example, wherein R1 and R2 are independently selected from methyl, ethyl, phenyl, vinyl, trifluolol,ropyl and cyanopropyl, and R is --R3--N--R5 or --R3--N--R5 X

W O96/19554 PCTrUS95/15142 wherein R3 is a divalent alkylene of about 1-20, preferably abowt 3-5 carbon atoms optionally substituted or interrupted by O atoms, ~4, R5 and R6 which may be the same or different are selected from H~ alkyl of about 1-20, preferably about 1-10, more preferably about 1~ carbons optionally substit~lte-l or interrupted by N and/or O atoms, and X~ is a monovalent anion such as halide, hydroxide, and tosylate, said aminoalkylsilicone including about 60~o or less, preferably from about 0.1-30%, more preferably from 0.2-10% and especially from about 0.5-2% of unit (1) on a repeating unit basis.

In a preferred embodiment, the aminoalkylsilicones comprise amodimethicones. Amodimethicones are polydimethylsiloxane polymers cont~inin~ aminoalkyl groups. The aminoalkyl groups may be present either pendant or at one or more ends of the polydimethylsiloxane chain Preferred are aminoalkylsilicones in which aminoalkyl moiety ~ is selected from (CH2)3NH2, (CH2)3NHCH2CH2NH2, (CH2)3N(CH2CH2OH)2, (CH2)3NH3+X-, and (CH2)3N(CH3)2(C18H37)+X-, and especially from (CH2)3NH2 and (CH2)3NHCH2CH2NH2. Also yrefelred are aminoalkyl silicones having an average molecular weight of about 5,000 and above, preîelably from about 5000 to about 100,000, more preferably from about 5000 to about 30,000.

Aminoalkylsilicone compounds suitable for use herein are well known.
Methods of preparing aminoalkylsilicones are given in, for example, US-A-2,930,809.

Examples of amodimethicones include Dow Corning's DC-929, DC-Q2-7224 and Q2-8075 and OSI's Magnasoft fluid, the latter being preferred.
These polymers comprise aminoalkyl groups affixed to a predomin~ntly polydimethylsiloxane structure. The typical structure of M~n~oft's aminoalkyl group-cont~ining units is -OSi(Me)C3H6NHCH2CH2NH2.

WO 96119554 PCTllJS9~ 142 The aminoalkylsilicone is generally present in a level of from about 0.01 % to about 25 %, preferably from about 0.1 % to about 5 ~, more preferably from about 0.5% to about 1.5~o by weight.

The denture cle~n.~ing compositions also incorporate an effervescence generator which in ~referled embodiments takes the form of a solid base material which in the presence of water releases carbon dioxide or oxygen with effervescence. The effervescence generator utilized in the compositions herein can be selected from ~enerators which are effective under acid, neutral or ~lk~line pH conditions, but preferably it consists of a combination of a generator which is effective or most effective under acid or neutral pH conditions and a generator which is effective or most effective under ~lk~line pH conditions. Effervescence generators which are effective under acid or neutral pH conditions include a combination of at least one alkali metal carbonate or bicarbonate, such as sodium bicarbonate, sodium carbonate, sodium sesquicarbonate, potassium carbonate, pot~sil-m bicarbonate, or mixtures thereof, in admixture with at least one non-toxic, physiologically-acceptable organic acid, such as tar~aric, fumaric, citric, malic, maleic, gluconic, succinic, salicylic, adipic or sulphamic acid, sodium fumarate, sodiurn or potassium acid phosphates, betaine hydrochloride or mixtures thereof. Of these, malic acid is preferred. Effervescence generators which are effective under ~lk~linP pH conditions include persalts such as alkali and ~lk~line earth metal peroxoborates as well as perborates, persulphates, percarbonates, perphosphates and mixtures thereof as previously described, for example, a mixture of an alkali metal perborate (anhydrous, mono- or tetrahydrate) with a monopersulphate such as Caroat R marketed by E I du Point de Nemours Co. and which is a 2:1:1 mixture of monopersulphate, potassium sulphate and potassium bisulphate and which has an active oxygen content of about 4.5 ~ .

In highly preferred compositions, the solid base material incorporates a (bi)carbonate/acid effervescent couple optionally in combination with a perborate/persulphate oxygen effervescence generator. The combination of generators is valuable for achieving optimum dissolution characteristics and pH conditions for achieving optimum cleaning and antimicrobial W O96/19554 PCTrU~95/15142 activity. The (bi)carbonate components generally comprise from about 5 % to about 65 %, preferably from about 25 % to SS % of the total composition; the acid components generally comprise from about 5% to about 50%, preferably from about 10% to about 30% of the total composition.

The compositions of the invention can be supplemented by other known components of denture cle~n~in~ formulations. An especially preferred additional component is an organic peroxyacid precursor, which in general terms can be defined as a compound having a titre of al least 1 .Sml of 0. lN sodium thiosulfate in the following peracid formation test.

A test solution is prepared by dissolving the following materials in 1000 mls distilled water:

sodium pyrophosphate (Na4P2o7- 1~H2~) 2.5g sodium perborate (NaBO2.H2O2.3H2O) having 10.4% available oxygen 0.615g sodium dodecylbenzene sulphonate 0.5g To this solution at 60~C an amount of activator is added such that for each atom of available oxygen present one molecular equivalent of activator is introduced.

The mixture obtained by addition of the activator is vigorously stirred and m~int~in~l at 60~C. After S minlltes from addition, a 100 ml portion of the solution is withdrawn and imme~ tely pipetted onto a mixture of 250 g cracked ice and 15 ml glacial acetic acid. Potassium iodide (0.4 g) is then added and the liberated iodine is immediately titrated with 0.1 N
sodium thiosulphate with starch as indicator until the first disappearance of the blue colour. The amount of sodium thiosulphate solution used in ml is the titre of the bleach activator.

The organic peracid precursors are typically compounds cont~inin.~ one or more acyl groups, which are susceptible to perhydrolysis. The preferred activators are those of the N-acyl or O-acyl compound type cont~ininP: a acyl radical R-CO wherein R is a hydrocarbon or substituted hydrocarbon group having preferably from about 1 to about 20 carbon atoms.
Examples of suitable peracid precursors include:

1) Acyl or~no~mides of the formula RCONR1R2, where RCO is carboxylic acyl radical, R1 is an acyl radical and R2 is an organic radical, as disclosed in US-A-3,117,148. Examples of compounds falling under this group include:

a) N,N - diacetyl~niline and N-acetylphth~limi~le;
b) N-acylhydantoins, such as N,N ' -diacetyl-5,5-dimethylhydantoin;
c) Polyacylated alkylene ~i~mines, such as N,N,N'N' -tetraacetylethylene~ mine (TAED) and the corresponding hexamethylene~ mine (TAHD) derivatives, as disclosed in GB-A-907,356, GB-A-907,357 and GB-A-907,358;
d) Acylated glycolurils, such as tetraacetylglycoluril, as disclosed in GB-A-1,246,338, GB-A-1,246,339 and GB-A-1,247,429.

2) Acylated sulphon~micles~ such as N-methyl-N-benzoyl-menth~ne sulphon~mi~le and N-phenyl-N-acetyl menthane sulphon~micle, as disclosed in GB-A-3,183,266.

3) Carboxylic esters as disclosed in GB-A-836,988, GB-A-963,135 and GB-A-1,147,871. Examples of compounds of this type include phenyl acetate, sodium acetoxy benzene sulphonate, trichloroethylacetate, sorbitol hexaacetate, fructose pentaacetate, p-nitrobenzaldehyde diacetate, isopropeneyl acetate, acetyl aceto hydroxamic acid, and acetyl salicylic acid. Other examples are esters of a phenol or substituted phenol with an alpha-chlorinated lower aliphatic carboxylic acid, such as chloroacetylphenol and chloroacetylsalicylic acid, as disclosed in US-A-3,130,165.

W O96/19554 PCTrUS95/15142 4) Carboxylic esters having the gernal formal Ac L wherein Ac is the acyl moiety of an organic carboxylic acid comprising an optionally substituted, linear or branched C6-C20 alkyl or alkenyl m,oiety or a C6-C20 alkyl-substituted aryl moiety and L is a leaving group, the conjugate acid of which has a pKa in the range from 4 to 13, for example oxybenzenesulfonate or oxybenzoate. Preferred compounds of this type are those wherein:
a) Ac is R3-CO and R3 is a linear or branched alkyl group cont~inin~ from 6 to 20, preferably 6 to 12, more preferably 7 to 9 carbon atoms and wherein the longest linear alkyl chain extending from and including the carbonyl carbon contains from 5 to 18, preferably 5 to 10 carbon atoms, R3 optionally being substit~lte~l (preferably alpha to the carbonyl m.oiety) by Cl, Br, OCH3 or OC2Hs. Examples of this class of material include sodium 3,5,5-trimethylhexanoyloxybenzene ~iulfonate, sodium 3,5,5-trimethylhexanoyloxybenzoate, sodium~ 2-ethylhexanoyl oxybenzenesulfonate, sodium nonanoyl oxybenzene sulfonate and sodium octanoyl oxybenezenesulfonate, the acyloxy group in each instance preferably being p-substituted;

b) Ac has the formula R3(AO)mXA wherein R3 is a linear or branched alkyl or alkylaryl group cont~inin.~ from 6 to 20, preferably from 6 to 15 carbon atoms in the alkyl moiety, Rs being optionally substituted by Cl, Br, OCH3, or OC2H~, AO
is oxyethylene or oxypropylene, m is from O to 100, X is 0, NR4 or CO-NR4, and A is CO, CO-CO, R6-CO, CO-R6-CO, or CO-NR4-R6-CO wherein R4 is Cl-C4 alkyl and lR6 is alkylene, alkenylene, arylene or alkarylene cont~ini~ from 1 to 8 carbon atoms in the alkylene or alkenylene moiety.
Bleach activator compounds of this type include carbonic acid derivatives of the formula R3(AO)mOCOL, succinic acid derivatives of the formula R30CO(CH2)2COL, glycollic acid derivatives of the formula R30CH2COL, hydroxypropionic acid derivatives of the formula R30CH2CH2COL, oxalic acid derivatives of the formula R30COCOL, maleic and fumaric acid derivatives of the formula R30COCH=CHCO]_, acyl aminocaproic acid derivatives of the formula R3CONR1(CH2)6COL, acyl glycine derivatives of the formula R3CONR1CH2COL, and amino-6-oxocaproic acid derivatives of the formula R3N(R1)CO(CH2)4COL. In the above, m is preferably from 0 to 10, and R3 is preferably C6-C12, more preferably C6-C1o alkyl when m is zero and Cg-C1s when m is non-zero. The leaving group L is as defined above.

5) Acyl-cyanurates, such as triacetyl- or tribenzoylcyanurates, as disclosed in US patent specification No. 3,332,882.

6) Optionally substituted anhydrides of benzoic or phthalic acid, for example, benzoic anhydride, m-chlorobenzoic anhydride and phthalic anhydride.

Of all the above, preferred are organic peracid precursors of types 1(c) and 4(a).

Where present, the level of peroxyacid bleach precursor by weight of the total composition is preferably from about 0.1% to about 10%, more ~refelably from about 0.5% to about 5% and is generally added in the form of a bleach precursor agglomerate.

The bleach precursor agglomerates preferred for use herein generally comprise a binder or agglomerating agent in a level of from about 5 % to about 40%, more especially from about 10~o to about 30% by weight thereof. Suitable agglomerating agents include polyvinylpyrrolidone, poly (oxyethylene) of molecular weight 20,000 to 500,000, polyethyleneglycols of molecular weight of from about 1000 to about 50,000, Carbowax having a molecular weight of from 4000 to 20,000, nonionic surf~ct~nts, fatty acids, sodium carboxymethyl cellulose, gelatin, fatty alcohols, phosphates and polyphosphates, clays, aluminosilicates and polymeric polycarboxylates. Of the above, polyethyleneglycols are highly preferled, especially those having molecular weight of from about 1,000 to about 30,000, preferably 2000 to about 10,000.

W O96/19S54 PCTrUS95/15142 Preferred from the viewpoint of optimum dissolution and pH
characteristics are bleach precursor agglomerates which comprise from about 10% to about 75%, preferably from about 20% to about 60% by weight thereof of peroxyacid bleach precursor, from about 5 % to about 60% preferably from about 5% to about 50%, more preferably from about 10% to about 40% of a (bi) carbonate/acid effervescent couple, from about 0% to about 20% of a peroxoboroate, and from about 5% to about 40%, preferably from about 10% to about 30% of an ag;glomerating agent.

The final bleach precursor granules desirably have an average particle size of from about 500 to about 1500, preferably from about 500 to about 1,000 um, this being valuable from the viewpoint of optimum dissolution pelrorlllance and aesthetics. The level of bleach precursor agglomerates, moreover, is preferably from about 1% to about 20%, more preferably from about 5% to about 15% by weight of composition.

The compositions of the invention can be in paste,~liquid, tablet, granular or powder form, although tablet-form compositions are highly ~referred herein. Compositions in tablet form can be single or multiple layered tablets.

The compositions of the invention can be supplemented by other usual components of denture cle~ncin~ formulations, especially surfactants, ch~l~tin~ agents, enzymes, flavorants, physiological cooling agents, antimicrobial compounds, dyestuffs, sweeteners, tablet binders and fillers, foam depress~nt~ such as dimethylpolysiloxanes, foam stabilizers such as the fatty acid sugar esters, preservatives, lubricants such as talc, m~n~sium stearate, finely divided amorphous pyrogenic silicas, etc. The free moisture content of the final composition is desirably less than about 1% and especially less than about 0.5%.

Tablet binders and fillers suitable for use herein include polyvinylpyrrolidone, poly (oxyethylene) of molecular weight 20,000 to 500,000, polyethyleneglycols of molecular weight of from about 1000 to about 50,000, Carbowax having a molecular weight of from 4000 to 20,000, nonionic surfactants, fatty acids, sodium carboxymethyl cellulose, WO 96119554 PCTIUS9~ 142 gelatin, fatty alcohols, clays, polymeric polycarboxylates, sodium carbonate, calcium carbonate, calcium hydroxide, magnesium oxide, m~nesium hydroxide carbonate, sodium sulfate, proteins, cellulose ethers, cellulose esters, polyvinyl alcohol, alginic acid esters, vegetable fatty materials of a pseudocolloidal character. Of the above, polyethyleneglycols are highly preferred, especially those having lmolecular weight of from about 1,000 to about 30,000, preferably from about 12,000 to about 30,000.

The surface active agent used in the compositions of the invention can be selected from the many available that are compatible with the other ingredients of the denture cleanser, both in the dry state and in solution.
Such materials are believed to improve the effectiveness of the other ingredients of the composition by aiding their penetration into the interdental surfaces. Also, these materials aid in the removal of food debris attached to the teeth. Between 0.1 and 5 percent by weight of the dry composition of a dry powder or granular anionic surface active agent, such as sodium lauryl sulfate, sodium N-lauroylsarcosinate, sodium lauryl sulfoacetate or dioctyl sodium sulfosuccinate or ricinoleyl sodium sulfosuccinate, may, for example, be included in the composition and preferably the surface active agent comprises between 0.5 and 4 percent of the composition.

Suitable cationic, non-ionic and ampholytic surface active agents include, for example, quaternary ammonium compounds such as ce~rltrimethyl~mmonium bromide, condensation products of alkylene oxides such as ethylene or propylene oxide with fatty alcohols, phenols, fatty amines or fatty acid alkanolamides, the fatty acid alkanol~mi-les themselves, esters of long-chained (Cg-C22) fatty acids with polyalcohols or sugars, for example glycerylmonostearate or saccharosemonolaurate or sorbitolpolyoxyethylenemono-or di-stearate, betaines, sulphobetaines or long-chain alkylaminocarboxylic acids.

Chelating agents beneficially aid cle~ning and bleach stability by keeping metal ions, such as calcium, m~nesium~ and heavy metal cations in solution. Examples of suitable chelating agents include sodium W O 96/19554 PC~rrUS9S/15142 tripolyphosphate, sodium acid pyrophosphate, tetrasodium pyrophosphate, aminopolycarboxylates such as nitrilotriacetic acid and ethylene~ mine tetracetic acid and salts thereof, and polyphosphonates and aminopolyphosphonates such as hydroxyethanediphosphonic aci~, ethylene~ mine tetramethylenephosphonic acid, diethylenetri~minepentamethylenephosphonic acid and salts thereof. The chelating agent selected is not critical except that it must be com~patible with the other ingredients of the denture cleanser when in the dry state and in aqueous solution. Advantageously, the chelating agent comprises between 0.1 and 60 percent by weight of the composition and preferably bet~,veen 0.5 and 30 percent. Phosphonic acid chelating agents, however, preferably comprise from about 0.1 to about 1 percent, preferably from about 0.1% to about 0.5 % by weight of composition.

Enzymes suitable for use herein are exemplified by proteases, ~lk~l~se~
amylases, lipases, dextranases, mutanases, glucanases etc.

Flavorants suitable for use in the compositions of the invention include wintergreen oil, oregano oil, bay leaf oil, peppermint oil, spearmint oil, clove oil, sage oil, s~s~fras oil, lemon oil, orange oil, anise oil, benzaldehyde, bitter almond oil, camphor, cedar leaf oil, marjoram oil, citronella oil, lavendar oil, mustard oil, pine oil, pine needle oil, rosemary oil, thyme oil, cinnamon leaf oil, and mixtures thereof.

Suitable antimicrobial compounds include thymol, menthol, triclosan, ~
hexylresorcinol, phenol, eucalyptol, benzoic acid, benzoyl peroxide, butyl paraben, methyl paraben, propyl paraben, salicylamides, and mixtures thereof.

The following Examples further describe and demonstrate the preferred embo~liments within the scope of the present invention.

96/19~54 PCT/US9~ 142 EXAMPLES I TO V

The following are representative denture cleansing tablets according tothe invention. The percentages are by weight of the total tablet. The tablets are made by compressing a mixture of the gr~n~ ted components in a punch and dye tabletting press at a pressure of about 105 kPa.

II III IV V
Malic Acid 12 10 15 - 14 Citric Acid - 10 - 15 Sodium Carbonate 10 8 10 6 10 Sulphamic Acid 5 - - 3 3 PEG 20,000 - 3 7 8 5 PVP 40,000 6 3 Sodium Bicarbonate 22 19 24.5 13 23 Sodium Perborate Monohydrate 15 12 16 30 15 Potassium Monopersulphate 15 18 13 - 14 Pyrogenic Silica - 3 Talc 2 EDTMPl FlavorS 2 1 2 1 2 M~n~coft Fluid4 1 5 0.5 10 Bleach Precursor Agglomerate 9 8 10 12 10 Bleach Precursor A~lomerate I II III IV V
TAED2 2 - 4 5 2.5 TMHoS3 2 3 Sulphamic Acid 2 2 2 2 3.5 Sodium Bicarbonate 0.5 0.2 0.2 0.5 2 PEG 6000 2.5 2 2.4 2.5 1.5 Dye - 0.8 1.4 2 0.5 1. Ethylene~ minetetramethylenephosphonic acid 2. Tetraacetylethylene ~ mine 3. Sodium 3,5,5-trimethylhexanoyloxybenzene sulfonate 4 M~n~oft Fluid 5 Peppermint-based flavor W O96/19554 PCTrUS95/15142 In Examples I to V above, the overall tablet weight is 3 g; diameter 25mm.

The denture cleansing tablets of Examples I to V display improved antiplaque efficacy together with excellent cleansing and anti-bacterial activity, cohesion and other physical and in-use performance characteristics .

Claims

1. A denture cleansing composition comprising an inorganic persalt bleaching agent, an effervescence generator and an aminoalkyl silicone.

2. A composition according to Claim 1 wherein the aminoalkylsilicone is a noncyclic, hydrophobic aminoalkylsilicone having a formula comprising two basic units:

1) (R1)m(R)nSiO(4-m-n)/2 wherein m+n is 1, 2 or 3; n is 1, 2 or 3; m is 0,1,2;and 2) (R1)a(R2)bSiO(4-a-b)/2 wherein a+b is 1, 2, or 3, and a and b are integers, wherein R1 and R2 are independently selected from H, alkyl and alkenyl of about 1 to about 10 carbons optionally substituted with fluoro or cyano groups, hydroxy, alkoxy, and acetoxy, and R is wherein R3 is a divalent alkylene of about 1-20 carbon atoms optionally substituted or interrupted by O atoms, R4, R5 and R6 which may be the same or different are selected from H, alkyl of about 1-20 carbons optionally substituted or interrupted by N
and/or O atoms, and X- is a monovalent anion, said aminoalkyl silicone including about 60% or less of unit (1) on a repeating unit basis.

3. A composition according to Claim 2 wherein the aminoalkyl silicone has a molecular weight of at least about 5,000, preferably from about 5000 to about 100,000.

4. A composition according to Claim 2 or 3 wherein R1 and R2 are independently selected from methyl, ethyl, phenyl, vinyl, trifluoropropyl and cyanopropyl.

5. A composition according to any of Claims 2 to 4 wherein R3 is a divalent alkylene having from 3 to 5 carbon atoms.

6. A composition according to any of Claims 2 to 5 wherein R is selected from (CH2)3NH2, (CH2)3NHCH2CH2NH2, (CH2)3N(CH2CH2OH)2, (CH2)3NH3+X-, and (CH2)3N(CH3)2(C18H37)+X-.

7. A composition according to any of Claims 1 to 6 wherein the aminoalkylsilicone is amodimethicone.

8. A composition according to any of Claims 1 to 7 comprising from about 0.01% to about 25%, preferably from about 0.1% to about 5% by weight of the aminoalkylsilicone.

9. A composition according to any of Claims 1 to 8 wherein the inorganic persalt bleaching agent comprises one or more bleaching agents selected from alkali metal persulfates, alkali metal perborates and mixtures thereof.

10. A composition according to any of the Claims 1 to 9 wherein the effervescence generator comprises a (bi)carbonate/acid effervescent couple.

11. A composition according to any of Claims 1 to 10 additionally comprising an organic peroxyacid bleach precursor.

12. A composition according to Claim 11 wherein the organic peroxyacid bleach precursor is selected from acylated polyalkyldiamines, especially tetraacetylethylenediamine, and carboxylic esters having the general formula AcL wherein Ac is the acyl moiety or an organic carboxylic acid comprising an optionally substituted, linear or branched C6-C20 alkyl or alkenyl moiety or a C6-C20 alkyl-substituted aryl moiety and L is a leaving group, the conjugate acid of which has a pKa in the range from 4 to 13.

13 Use of an aminoalkyl silicone as antiplaque agent in a denture cleansing composition.