EP0821720B1 - Anti-foaming composition - Google Patents

Description

The present invention relates to anti-foam compositions comprising at least one nonionic defoaming surfactant as well as solubilizing agent.

Certain cleaning compositions in cleaning operations industrial cleaning such as cleaning bottles or washing soils can cause significant foam to form. She is in particular due to the presence of food soiling or residues of glue on the bottles. In order to reduce or even prevent, the formation of this foam, it is known to add to the cleaning composition one or more defoaming surfactants. These defoaming surfactants are generally of the non-ionic type. However, these defoaming surfactants have limited use due to their low solubility in highly concentrated alkaline cleaning compositions, which may include up to 50% by weight of soda or potash. Under these conditions, said defoaming surfactants are poorly soluble. In order to avoid having to decrease the concentration of alkaline agent at the expense of cleaning performance, it is known to combine the defoaming surfactant with solubilizing agents, such cumene sulfonates and xylene sulfonates or organic solvents.

Alkylpolyglycosides have also been described as agents solubilizers of nonionic defoaming surfactants. The alkylpolyglycosides are well-known nonionic surfactants. Their manufacturing process is for example described in patent application EP-A-0.077.167.

Patent application EP-A-0.489.777 describes compositions antifoam comprising alkylpolyglycosides including the alkyl chain has 6 to 12 carbon atoms. However, to date, the only alkylpolyglycosides marketed as solubilizers for defoaming nonionic surfactants, are 50-50 mixtures (by weight) alkylpolyglycosides having, respectively, an alkyl chain with 8 atoms of carbon and an alkyl chain with 10 carbon atoms. This type of agents solubilizers is marketed by the company UNION CARBIDE under the TRITON BG 10 brand.

A first object of the present invention consists of a anti-foam composition comprising a nonionic surfactant and a particular alkylpolyglycoside, having a good solubilizing power of the agent defoaming surfactant.

According to another aspect, the invention also relates to a composition cleaning agent comprising an anti-foaming composition based on (i) a nonionic defoaming surfactant and (ii) said particular alkylpolyglycoside.

• R représente un radical 2-éthylhexyle ;
• Z est le reste d'un sucre ; et
• n est compris entre 1 et 5.

The invention thus relates to an anti-foaming composition comprising at least one nonionic defoaming surfactant and at least one alkylpolyglycoside of formula (I): R (O) Z _n in which :

• R represents a 2-ethylhexyl radical;
• Z is the remainder of a sugar; and
• n is between 1 and 5.

It has been found that such an alkylpolyglycoside allows, in a way surprisingly, to reinforce the anti-foaming effect of said nonionic surfactant. There is therefore has a real synergy between the latter and the compound of formula (I).

The residue Z can be chosen from the residues of the following compounds : glucose, dextrose, sucrose, fructose, galactose, maltose, maltotriose, lactose, celobiose, mannose, ribose, dextran, tallose, xylose and levoglucosan. Among these compounds, dextrose, fructose and maltose are preferred, with glucose being most particularly preferred.

According to an advantageous aspect of the invention, n is between 1.1 and 2.

ou

n, m, identiques ou différents, étant compris entre 1 et 50. Un tensioactif non-ionique démoussant selon l'invention peut comporter un ou plusieurs groupes éthoxylés ou propoxylés, ces groupes étant distribués de manière séquencée ou aléatoire (random). Ces groupes éthoxylés ou propoxylés peuvent ou non être bloqués par un radical alkyle en C₄-C₈, de préférence un radical butyle, par un radical benzyle ou par l'oxyde de butylène. On entend par le terme "bloqué" le fait que ces groupes comportent en bout de chaíne non pas un atome d'hydrogène mais un radical tel que mentionné ci-dessus.The defoaming nonionic surfactants according to the invention are generally chosen from those comprising one or more groups chosen from mono-ethoxylated (OE) or polyethoxylated (POE) groups, of formula (CH ₂ CH ₂ O) _n , and the groups mono-propoxylated (OP) or polypropoxylated (POP), with formulas

or

n, m, identical or different, being between 1 and 50. A nonionic defoaming surfactant according to the invention can comprise one or more ethoxylated or propoxylated groups, these groups being distributed in a sequenced or random manner. These ethoxylated or propoxylated groups may or may not be blocked by a C ₄ -C ₈ alkyl radical, preferably a butyl radical, by a benzyl radical or by butylene oxide. The term "blocked" means the fact that these groups comprise at the end of the chain not a hydrogen atom but a radical as mentioned above.

• R représente un groupe hydrophobe choisi de préférence parmi les groupes alkyle, linéaire ou ramifié, ayant de 6 à 14 atomes de carbone;
• X représente un atome d'azote ou un atome d'oxygène ;
• OE représente un groupe oxyde d'éthylène (CH₂-CH₂O) ;
• OP représente un groupe oxyde de propylène CH₂-CH(CH₃)-O ou CH(CH₃)-CH₂-O;
• a représente un nombre entier compris entre 1 et 50 ;
• d représente un nombre entier compris entre 0 et 50 ;
• Y représente un atome d'hydrogène ou un groupe bloquant choisi parmi un radical alkyle ayant de 4 à 8 atomes de carbone, de préférence un radical butyle, un radical benzyle, un groupe oxyde de butylène; ou encore un groupe (OP)_bH ou [(OP)_b-(OE)_cH] dans lesquels b, c représentent indépendemment un nombre entier compris entre 1 et 50 ; et
• n est égal à 1 lorsque X représente un atome d'oxygène et n est égal à 2 lorsque X représente un atome d'azote.

Defoaming nonionic surfactants preferred in the context of the present invention can be represented by the general formula: RX - [(OP) _d - (OE) _a -Y] _n in which :

• R represents a hydrophobic group preferably chosen from alkyl groups, linear or branched, having from 6 to 14 carbon atoms;
• X represents a nitrogen atom or an oxygen atom;
• OE represents an ethylene oxide group (CH ₂ -CH ₂ O);
• OP represents a propylene oxide group CH ₂ -CH (CH ₃ ) -O or CH (CH ₃ ) -CH ₂ -O;
• a represents an integer between 1 and 50;
• d represents an integer between 0 and 50;
• Y represents a hydrogen atom or a blocking group chosen from an alkyl radical having from 4 to 8 carbon atoms, preferably a butyl radical, a benzyl radical, a butylene oxide group; or a group (OP) _b H or [(OP) _b - (OE) _c H] in which b, c independently represent an integer between 1 and 50; and
• n is equal to 1 when X represents an oxygen atom and n is equal to 2 when X represents a nitrogen atom.

The nonionic defoaming surfactants which are particularly preferred in the context of the present invention are chosen from the group consisting of polyethoxylated amines, polyethoxylated and polypropoxylated amines, polyethoxylated alcohols blocked by a C ₄ -C ₈ alkyl radical, preferably blocked with a butyl radical, or also blocked with a benzyl radical or butylene oxide, and polyethoxylated and / or polypropoxylated alcohols.

dans laquelle :

• R₁ est un radical alkyle, linéaire ou ramifié, comprenant 6 à 14 atomes de carbone, de préférence 8 à 10 atomes de carbone ;
• a, b et c, identiques ou différents, sont des entiers compris entre 1 et 10.

The particularly preferred defoaming nonionic surfactants are those of formula (II):

in which :

• R ₁ is an alkyl radical, linear or branched, comprising 6 to 14 carbon atoms, preferably 8 to 10 carbon atoms;
• a, b and c, identical or different, are integers between 1 and 10.

An anti-foaming composition according to the invention can be provided in concentrated or diluted form, ready to use.

When it is in concentrated form, it can comprise from 10 to 50% by weight of at least one compound of formula (I) and 20% to 70% by weight of at least one nonionic defoaming surfactant.

When in diluted form, it may include 0.004% to 10% by weight of at least one compound of formula (I) and 0.004% at 20% by weight of at least one nonionic defoaming surfactant.

This anti-foam composition generally comprises a compound of formula (I) and a nonionic surfactant defoaming in a weight ratio between 1/10 and 10/1, preferably between 1/5 and 5/1.

According to another aspect of the invention, it relates to the use an anti-foaming composition as defined above as an agent anti-foam.

According to yet another aspect of the invention, it relates the use of an alkylpolyglycoside of formula (I) above mentioned as agent solubilizer of a nonionic defoaming surfactant.

According to yet another aspect of the invention, it relates to cleaning compositions comprising an anti-foaming composition such as described above. This cleaning composition according to the invention comprises usually 2 to 50% by weight of one or more alkaline agents. The agent alkali used in these compositions is usually sodium hydroxide or potash. The cleaning compositions according to the invention can contain a content such as the anti-foaming composition that the concentration of defoaming nonionic surfactant in said composition cleaner is between 0.001 and 2% by weight.

The following examples are intended to illustrate the present invention.

Example 1

(i) on a préparé différentes solutions comprenant (% en poids) :

• tensioactif démoussant⁽¹⁾ :   0,006
• APG :   0,006
• base alcaline à 10 %⁽²⁾ :   3
• lait en poudre Régilait® en dispersion à 10 % :   7,5
• eau désionisée,   q.s.p. 100

⁽¹⁾ : alcool de formule (II) précitée, commercialisé par la société S.E.P.P.I.C., sous la marque SIMULSOL™ NW 342
⁽²⁾ : base alcaline comprenant (% en poids) : tripolyphosphate de sodium : 3,5 métasilicate de sodium 5H₂O : 4,2 carbonate de sodium anhydre : 2,3 eau désionisée, q.s.p. 100

(ii) On a soumis la solution à une agitation rotative, pendant trois minutes et on a mesuré la hauteur de mousse (en mm) formée, après un repos de 5 secondes. L'agitation était telle qu'une solution similaire, mais ne comprenant ni tensioactif démoussant, ni APG, formait une mousse d'une hauteur de 30 mm.

We tested the defoaming power of different alkylpolyglucosides (APG) of variable alkyl chain length according to the following procedure:

(i) various solutions were prepared comprising (% by weight):

• defoaming surfactant ⁽¹⁾ : 0.006
• APG: 0.006
• 10% alkaline base ⁽²⁾ : 3
• Régilait® milk powder 10% dispersion: 7.5
• deionized water, qs 100

⁽¹⁾ : alcohol of formula (II) above, sold by the company SEPPIC, under the brand SIMULSOL ™ NW 342
⁽²⁾ : alkaline base comprising (% by weight): sodium tripolyphosphate: 3.5 sodium metasilicate 5H ₂ O: 4.2 anhydrous sodium carbonate: 2.3 deionized water, qs 100

(ii) The solution was subjected to rotary stirring for three minutes and the height of foam (in mm) formed was measured after standing for 5 seconds. The agitation was such that a similar solution, but comprising neither defoaming surfactant nor APG, formed a foam with a height of 30 mm.

The results obtained are shown in Table I. APG (alkyl chain) Foam height (mm) n-hexyl 10.5 n-octyl 12.5 2-ethylhexyl 10 n-octyl + n-decyl (50/50 mixture by weight) 15.5

These results show that compositions according to the invention comprising an APG in which the alkyl chain is a 2-ethylhexyl radical, makes it possible to obtain a defoaming power greater than that obtained with a 50/50 mixture of C ₈ - APG - C ₁₀ or with APGs comprising an n-octyl or n-hexyl radical.

We can note that a composition not including APG but only the defoaming surfactant produces a foam height of 14 mm.

Example 2

• on a préparé 100 g d'une solution comprenant (en g) :
  • SIMULSOL™ NW 342   :   0,1
  • NaOH   :   5
  • H₂O,   q.s.p. 100
• la solution obtenue est biphasique et trouble ;
• on verse dans cette solution biphasique différents agents solubilisants consistant en des APG à différentes longueurs de chaíne alkyle ou des agents solubilisants classiques, à savoir le xylène sulfonate d'ammonium et le cumène sulfonate d'ammonium ;
• on interrompt l'introduction de l'agent stabilisant dès que la solution biphasique est devenue parfaitement limpide et monophasique ;
• le poids en agent solubilisant requis pour obtenir une solution limpide représente son pouvoir solubilisant.

The solubilizing power of different APGs was tested against SIMULSOL NW 342 according to the following procedure:

• 100 g of a solution were prepared comprising (in g):
  • SIMULSOL ™ NW 342: 0.1
  • NaOH: 5
  • H ₂ O, qs 100
• the solution obtained is biphasic and cloudy;
• is poured into this two-phase solution different solubilizing agents consisting of APGs at different lengths of alkyl chain or conventional solubilizing agents, namely xylene sulfonate ammonium and cumene sulfonate ammonium;
• the introduction of the stabilizing agent is interrupted as soon as the biphasic solution has become perfectly clear and monophasic;
• the weight of solubilizing agent required to obtain a clear solution represents its solubilizing power.

The results obtained are shown in Table II below: Solubilizing agent Weight (in g) of solubilizing agent to obtain a clear solution N-hexyl chain APG 3.5 2-ethylhexyl APG 0.96 xylene ammonium sulfonate 1.6 ammonium cumene sulfonate 3

These results show that an alkylpolyglucoside comprising a n-hexyl chain has a weak solubilizing power, and in any case less than that of a conventional solubilizing agent of the cumene and xylene type. On the contrary, a 2-ethylhexylalkyl polyglucoside has good potency solubilizing.

Claims (13)

1. Anti-foaming composition comprising at least one defoaming nonionic surfactant and at least one alkylpolyglycoside of formula (I): R(O)Z_n    in which:

   R represents a 2-ethylhexyl radical,

   Z is a sugar residue, and

   n is between 1 and 5.
2. Composition according to Claim 1, characterized in that Z is a glucose residue.
3. Composition according to either of Claims 1 and 2, characterized in that n is between 1.1 and 2.
4. Composition according to one of Claims 1 to 3, characterized in that the nonionic defoaming surfactant comprises one or more polyethoxylated, polypropoxylated or polyethoxylated and polypropoxylated groups.
5. Composition according to Claim 4, characterized in that the nonionic defoaming surfactant corresponds to the general formula: R-X-[(PO)_d-EO)_a-Y]_n in which:

   R represents a hydrophobic group preferably chosen from linear or branched alkyl groups having from 6 to 14 carbon atoms;

   X represents a nitrogen atom or an oxygen atom;

   EO represents an ethylene oxide group (CH₂-CH₂O);

   PO represents a propylene oxide group CH₂-CH(CH₃)-O or CH(CH₃)-CH₂-O;

   a represents an integer between 1 and 50;

   d represents an integer between 0 and 50;

   Y represents a hydrogen atom or a blocking group chosen from an alkyl radical having from 4 to 8 carbon atoms, preferably a butyl radical, a benzyl radical, a butylene oxide group; or alternatively a group (PO)_bH or [(PO)_b-(EO)_cH] in which b and c independently represent an integer between 1 and 50; and

   n is equal to 1 when X represents an oxygen atom and n is equal to 2 when X represents a nitrogen atom.
6. Composition according to Claim 5, characterized in that the nonionic defoaming surfactant is chosen from the group consisting of polyethoxylated amines, polyethoxylated and polypropoxylated amines, polyethoxylated alcohols blocked with a C₄-C₈ radical, preferably blocked with a butyl radical, or alternatively blocked with a benzyl radical or butylene oxide, and polyethoxylated and/or polypropoxylated alcohols.
7. Composition according to Claim 6, characterized in that the nonionic defoaming surfactant is a compound of formula (II):

   

   in which:

   R₁ is a linear or branched alkyl radical comprising 6 to 14 carbon atoms, preferably 8 to 10 carbon atoms;

   a, b and c, which may be identical or different, are integers between 1 and 10.
8. Composition according to one of Claims 1 to 7, characterized in that the weight ratio between the compound of formula (I) and the nonionic defoaming surfactant is between 1/10 and 10/1, preferably between 1/5 and 5/1.
9. Use of a composition according to one of Claims 1 to 8 as an anti-foaming agent.
10. Use of an alkylpolyglycoside of formula (I) as defined in any one of Claims 1 to 3, as a solubilizing agent for a nonionic defoaming surfactant.
11. A cleaning composition, characterized in that it comprises an anti-foaming composition according to one of Claims 1 to 8.
12. A cleaning composition according to Claim 11, characterized in that it comprises from 2 to 50% by weight of an alkaline agent.
13. A cleaning composition according to Claim 11 or 12, characterized in that it comprises from 0.001% to 2% by weight of a nonionic defoaming surfactant.