WO2020109022A1

WO2020109022A1 - Preserved cleaning compositions

Info

Publication number: WO2020109022A1
Application number: PCT/EP2019/081362
Authority: WO
Inventors: Thomas Richard POINTON
Original assignee: Unilever NV; Conopco Inc
Current assignee: Unilever NV; Conopco Inc
Priority date: 2018-11-30
Filing date: 2019-11-14
Publication date: 2020-06-04
Anticipated expiration: 2021-05-30

Abstract

The present invention relates to a liquid detergent composition comprising a non-ionic surfactant; a short chain (C1 to C6), un saturated, organic acid or salt thereof having at least two carboxyl groups, and to a method of preparing such a composition and to the use of such a composition.

Description

PRESERVED CLEANING COMPOSITIONS

Field of the Invention

The present invention relates to the area of preservation chemicals for liquid detergent compositions, in particular to liquid detergent compositions for cleaning hard surfaces leaning compositions.

Background

In the cleaning industry, there is a constant need for preservation chemicals, especially preservation chemicals that are from natural sources, that are abundant and readily available.

A large number of antimicrobial active compounds are already employed in the cleaning compositions, but alternatives are continually sought after. Not all

antimicrobial agents have adequate preservation properties and thus the new for new preservation chemicals is particularly required. It is noted that substances used in the domestic cleaning compositions for domestic use must be:

- Toxicologically acceptable

Readily tolerated by the skin in case of skin contact via e.g. splashes

Stable

Largely and preferably completely odourless

inexpensive to prepare (i.e. employing standard processes and/or starting from standard precursors)

easy to formulate (i.e. preferably liquid) and should not be detrimental to the final product.

The present inventors have found a preservation chemical suitable for use with cleaning compositions in particular to hard surface cleaning compositions.

Description of the Invention

The present invention relates to a liquid detergent composition comprising:

a) 1 to 50% by weight of a non-ionic surfactant, b) 0.1 to 5% by weight of a preservation system comprising a short chain (Ci to Ce), unsaturated, organic acid or salt thereof having at least two carboxyl groups,

c) water; and

wherein the non-ionic surfactant provides at least 90 wt.% of the total amount by weight of surfactant contained in the composition;

wherein the short chain unsaturated organic acid is itaconic acid or salt thereof.

The invention further relates to a method of preserving a composition as defined herein by the use of; a short chain (C1 to C6), unsaturated, organic acid or salt thereof having at least two carboxyl groups.

Detailed Description of the Invention

Compositions of the invention comprise a short chain (C1 to C6), unsaturated, organic acid or salt thereof. The organic acid comprises two carboxyl groups. The unsaturation occurs on a side chain. The organic acid is itaconic acid or salt thereof.

Preferably the total level of short chain (C1 to C6), unsaturated, organic acid or salt thereof, in particular itaconic acid in the total composition is from 0.05 to 7 wt% of the total composition, more preferably 0.1 to 5 wt% most preferably from 0.2 to 3 wt%. Preferably, the composition comprises at least 0.5% by weight of itaconic acid.

The non-ionic surfactant is preferably selected from the group consisting of primary alcohol ethoxylates, secondary alcohol ethoxylates, alkylphenol ethoxylates, alkylaminoalkoxylates ethylene-oxide-propylene oxide condensates on primary alkanols, tertiary amino oxides and alkylpolyglycosyls.

Suitable alcohol ethoxylates are preferably selected from the NEODOL type (Shell),. Suitable NEODOL alcohol ethoxylates are NEODEL 91 (C9-C1 1 alcohols), NEODOL 23 (C12-13 alcohols), NEODOL 25 (C12-15 alcohols), NEODOL 45 (C14-15 alcohols), NEODOL 135 (C11-13-15 alcohols), NEODOL 1 , (C1 1 alcohol), NEODOL 3, (C13 alcohol), and NEODOL 5, (C15 alcohol).

Further suitable are preferably linear- and methyl-branched SAFOL type alcohol ethoxylates. The alcohol consists of approximately 55% C12 and 45% C13 carbon chain isomers. The alcohol derivatizes like highly linear alcohol and consists of approximately 50% linear and 50% branched isomers. Monobranched alcohols such as, ISALCHEM type alcohol ethoxylates, consist of a set of structural isomers which are all branched in the 2-alkyl position. Products in the range of C11 to C14/C15 are available from SASOL. ISOFOL alcohols are single isomer products available from C12 up to C32, from SASOL.

Yet further suitable alcohol ethoxylates are preferably selected from Imbentin alcohol ethoxylates (KOLB AG) and Lutensol TDA 10 (BASF), which is a 10-mole ethylene oxide adduct of tridecyl alcohol.

The non-ionic surfactant is preferably an alkylaminoalkoxylate according to the formula:

R-N(H)-(CH₂CH₂0)x-(CH₂CH₂CH₂0)y

where:

R is a linear or branched hydrocarbon radical containing

1 to 12 carbon atoms; and,

X and y are integer numbers selected so that the total molecular weight of the surfactant exhibits an average molecular weight of from about 2000 to about 8000.

Alternatively, the nonionic surfactant is preferably an alkylpolyoxyether according to the formula:

CxHy-0-(CH₂CH(CH₃)0)_m-(CH₂CH₂0)_n-H

where:

x is from 6-24;

y is from 17-49;

m is from 0-10 and n is from 1-40;

wherein the total molecular weight of the surfactant exhibits an average molecular weight of from about 500 to about 8000.

Suitable non-ionic surfactants include the condensation products of a higher alcohol (e.g., an alkanol containing about 8 to 18 carbon atoms in a straight or branched chain configuration) condensed with about 5 to 30 moles of ethylene oxide (n is from 5 to 30 and m is zero), for example, lauryl or myristyl alcohol condensed with about 16 moles of ethylene oxide (EO), tridecanol condensed with about 6 moles of EO, myristyl alcohol condensed with about 10 moles of EO per mole of myristyl alcohol, the condensation product of EO with a cut of coconut fatty alcohol containing a mixture of fatty alcohols with alkyl chains varying from 10 to about 14 carbon atoms in length and wherein the condensate contains either about 6 moles of EO per mole of total alcohol or about 9 moles of EO per mole of alcohol and tallow alcohol ethoxylates containing 6 EO to 11 EO per mole of alcohol.

Suitable examples of the non-ionic surfactant is lauryl alcohol condensed with 5, 6, 7, 8 and 9 moles of ethylene oxide (Laureth 5, Laureth 6, Laureth 7, Lauerth 8 and Laureth 9), condensates of 2 to 30 moles of ethylene oxide with sorbitan mono- and tri-Cio-C2o alkanoic acid esters having a HLB of 8 to 15, preferably polyoxyethylene (4) sorbitan monolaurate, polyoxyethylene (4) sorbitan monostearate, polyoxyethylene (20) sorbitan trioleate and polyoxyethylene (20) sorbitan tristearate.

Particularly preferred is lauryl alcohol condensed with 5, 6, 7, 8 and 9 moles of ethylene oxide (Laureth 5, Lauerth 6, Laureth 7, Laureth 8 and Laureth 9), more preferably lauryl alcohol condensed with 5, 7 and 9 moles of ethylene oxide (Laureth 5, Laureth 7 and Laureth 9).

Suitable example of non-ionic surfactants where m is 1 or greater are Plurafac type surfactants (BASF), where X is from 6 to 10, m is 3 and n is 6 to 8 C6-10-(PO)3(EO)6, the Lutensol series surfactants, for examples where X is 10 and m is 1 to 2 and n is 4 to 14 or the Ecosurf series of surfactants (DOW), for example where X is 6 to 12, m is 3 to 4 and n is 4 to 9.

The non-ionic surfactant is preferably, an amine oxide according to the formula:

R¹R²R³N-0,

where R¹ is an alkyl group of 8 to 20 carbon atoms and R² and R³ are each alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms. Preferably, wherein R¹ is a an alkyl group of 10 carbon atoms, R² and R³ are a (CFhCH^OH group. An especially preferred amine oxide is AO-14-2 from Tomah Products, Inc.

The non-ionic surfactant is preferably an alkylpolyglycosyl containing a C6-22 fatty alcohol residue, more preferably a Ce-ie fatty alcohol residue, wherein the glycosyl residue of the alkyl polyglycoside preferably comprises a linear oligo- or

polysaccharide. Preferably, the non-ionic surfactant is a rhamnolipids. Rhamnolipids are a class of glycolipid. They are constructed of rhamnose combined with beta- hydroxy fatty acids. Rhamnose is a sugar. Fatty acids are ubiquitous in animals and plants. The carboxyl end of the fatty acid end is connected to the rhamnose. Rhamnolipids are compounds of only three common elements; carbon, hydrogen, and oxygen. They are a crystalline acid.

Rhamnolipids may be produced by strains of the bacteria Pseudomonas aeruginosa. There are two major groups of rhamnolipids; mono-rhamnolipids and di-rhamnolipids.

Mono-rhamnolipids have a single rhamnose sugar ring. A typical mono-rhamnolipid produced by P. aeruginosa is L-rhamnosyl- -hydroxydecanoyl- -hydroxydecanoate (RhaCioCio). It may be referred to as Rha-CiO-CiO, with a formula of C26H48O9. Mono- rhamnolipids have a single rhamnose sugar ring. The lUPAC Name is 3-[3- [(2R,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan- 2-yl]oxydecanoyloxy]decanoic acid.

Di-rhamnolipids have two rhamnose sugar rings. A typical di-rhamnolipid is L- rhamnosyl-L- rhamnosyl- -hydroxydecanoyl- -hydroxydecanoate (Rha2CioCio). It may be referred to as Rha- Rha-C-io-C-io, with a formula of C32H ₅₈0i₃. The lUPAC name is 3-[3-[4,5-dihydroxy-6-methyl-3-(3,4,5-trihydroxy-6-methyloxan-2-yl)oxyoxan-2- yljoxydecanoyloxyjdecanoic acid.

The non-ionic surfactant provides at least 90 wt.% of the total amount by weight of surfactant contained in the composition. Preferably, the non-ionic surfactant provides at least 95 wt.% of the total amount by weight of surfactant contained in the composition, even more preferably, the non-ionic surfactant provides at least 100 wt.% of the total amount by weight of surfactant contained in the composition.

Preferably, the preservation system further comprises an additional preservation chemical selected from: aromatic alcohol, benzoic acid or a salt thereof, terpineol, geraniol, perillyl alcohol, menthol, terpinene, linalool, citronellol and mixtures thereof thereof.

The aromatic alcohol is preferably selected from group consisting of ethylvanillin, eugenol, thymol, P-hydroxybenzaldehyde, 4n butyl phenol, P-hydroxyacetophenone, vanillin, salicylic acid or salt thereof, o-cymen-5-ol, carvacrol and mixtures thereof. Preferably, the pH of the composition is in the range of 2 to 12, more preferably in the range of 2 to 1 1 , even more preferably in the range of 3 to 10, most preferably in the range 3 to 7. The composition further comprises water. Preferably 80 to 95%, more preferably 90 to 98 wt.%. Preferably not less than 80 wt.% water, still more preferably not less than 85 wt.%.

The composition preferably comprises less than 1 % by weight of silicone.

Optional Ingredients

The composition according to the invention may contain other ingredients which aid in the cleaning or sensory performance. Compositions according to the invention can also contain, in addition to the ingredients already mentioned, various other optional ingredients such as thickeners, colorants, preservatives, polymers, anti-microbial agents, perfumes, pH adjusters, sequesterants, alkalinity agents and hydrotropes. Typically, the compositions according to the invention comprise an alkyl fatty acid. Preferably, the alky fatty acid is a mixture of fatty acids comprising an alkyl fatty acid selected from the group consisting of lauric acid, caprylic acid, capric acid, myristic acid, palmitic acid, stearic acid and mixtures thereof. Mixtures of alkyl fatty acids are also known as coconut fatty acids, available from Croda (UK). Preferably alkyl fatty acids are present in a range of 0 to 1 wt.%, more preferably 0.01 to 0.5, even more preferably 0.05 to 0.25 wt.%. In a second aspect, the present invention relates to a. method for cleaning a hard surface comprising the steps of diluting 1 part of a composition according to claims 1- 10 with 2-50 parts water to provide a cleaning solution and contacting the hard surface with the cleaning solution. Hard surface’, as used herein, typically means utensils or kitchenware, kitchen tops, floors, sinks, tiles, kitchen floors and bathrooms.

In a third aspect, the present invention relates to a method of preserving a cleaning composition comprising the steps of combining a short chain (Ci to Ce), unsaturated, organic acid or salt thereof having at least two carboxyl groups, wherein the short chain unsaturated organic acid is itaconic acid or salt thereof, with a nonionic surfactant. The invention will now be illustrated by means of the following non-limiting examples.

Examples Liquid detergent compositions were prepared having the base formulation according to Table 1 :

Table 1

Citric acid, lactic acid and itaconic acid were added to the cleaning composition an amount of 1.0 wt.%, based on the weight of the composition.

Sample preparation Itaconic acid, lactic acid and citric acid were purchased from Sigma-Aldrich. Six samples of unpreserved conditioner were dosed with 0.5% and 1% (w/w) itaconic acid, citric acid and lactic acid separately. An unpreserved sample was kept as a control. Each dosed product was adjusted to pH 5 using 50% sodium hydroxide (Sigma- Aldrich).

Challenge test method

A modified challenge test method was performed on a subsample of both the unpreserved and each dosed product. The bacterial challenge test microorganisms are summarised in data tables with an inoculum level of 2.69 X 10⁷ CFU/G introduced into each sample. The microbial challenge pools were added to each sample container at a ratio of 1 :10 microorganism to product. Each inoculated product sample was mixed with a sterile spatula to ensure a homogenous distribution of the inocula throughout the product. Table 2: Microbial Challenge test pool and Inoculum levels

Both the inoculum level and the level of microorganism within each sample was quantified using a Total Viable Count (TVC) pour plate method after contact times as indicated in Table 3. A 1 :10 dilution was made with a subsample of each product, performed separately in Peptone (0.1 %)/ tween 80 (2%) neutralising agent. A 1 :10 and 1 :100 dilution of each subsample was performed and pour plates produced at each dilution using tryptone soya agar. Plates were incubated at 28°C for 48 hours and then examined for growth. Visible colonies were counted with the aid of a Quebec Colony Counter and recorded for analysis against the challenge test criteria.

Table 3: Microbial challenge test against Pseudomonas aeruginosa, Burkholderia cepacia and Pseudomonas putida log kill

Claims

1. A liquid detergent composition comprising:

a) 1 to 50% by weight of a non-ionic surfactant,

b) 0.1 to 5% by weight of a preservation system comprising a short chain (Ci to Ce), unsaturated, organic acid or salt thereof having at least two carboxyl groups,

c) water;

and wherein the non-ionic surfactant provides at least 90 wt.% of the total amount by weight of surfactant contained in the composition;

2. The composition according to any of the preceding claims wherein the pH is in the range of 2 to 12, more preferably in the range of 2 to 1 1 , even more preferably in the range of 3 to 10, most preferably in the range 3 to 7.

3. The composition according to any of the preceding claims, wherein the non-ionic

surfactant is selected from the group consisting of primary alcohol ethoxylates, secondary alcohol ethoxylates, alkylphenol ethoxylates, alkylaminoalkoxylates, alkylpolyoxyether, ethylene-oxide-propylene oxide condensates on primary alkanols, tertiary amino oxides alkylpolyglycosyls and mixtures thereof, preferably a primary or secondary alcohol ethoxylate.

4. The composition according to according to any of the preceding claims, wherein the non-ionic surfactant comprises an alkylaminoalkoxylate according to the formula:

R-N(H)-(CH₂CH₂0)x-(CH₂CH₂CH₂0)y

where:

R is a linear or branched hydrocarbon radical containing

1 to 12 carbon atoms; and,

5. The composition according to according to any of the preceding claims, wherein the nonionic surfactant comprises an alkylpolyoxyether according to the formula:

CxHy-0-(CH₂C(CH₃)CH0)n-(CH₂CH₂0)m-H

where: x is from 6-24;

y is from 17-49;

m is from 0-10 and n is from 1-40;

6. The composition according to according to any of the preceding claims, wherein the non-ionic surfactant comprises an amine oxide according to the formula:

R¹R²R³N-0,

where R¹ is an alkyl group of 8 to 20 carbon atoms and R² and R³ are each alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms.

7. The composition according to any of the preceding claims, wherein the non-ionic

surfactant comprises an alkylpolyglycosyl containing a Ce-22 fatty alcohol residue, more preferably a Ce-ie fatty alcohol residue, wherein the glycosyl residue of the alkyl polyglycoside preferably comprises a linear oligo- or polysaccharide.

8. The composition according to any of the preceding claims, wherein the non-ionic

surfactant is lauryl alcohol condensed with 5, 7 and 9 moles of ethylene oxide (Laureth 5, Laureth 7 and Laureth 9), condensates of 2 to 30 moles of ethylene oxide with sorbitan mono- and tri-Cio-C2o alkanoic acid esters having a HLB of 8 to 15, preferably polyoxyethylene (4) sorbitan monolaurate, polyoxyethylene (4) sorbitan monostearate, polyoxyethylene (20) sorbitan trioleate and polyoxyethylene (20) sorbitan tristearate.

9. The composition according to any of the preceding claims, wherein the preservative system further comprises an additional preservation chemical selected from an aromatic alcohol, benzoic acid or a salt thereof, terpineol, geraniol, perillyl alcohol, menthol, terpinene, linalool, citronellol and mixtures thereof.

10. The composition according to any of the preceding claims, comprising at least 0.5% by weight of itaconic acid.

1 1. The composition according to any of the preceding claims, comprising 60-90% by weight of water.

12. The composition according to any of the preceding claims, comprising less than 1% by weight of silicone.

13. A method for cleaning a hard surface comprising the steps of diluting 1 part of a composition according to claims 1-10 with 2-50 parts water to provide a cleaning solution and contacting the hard surface with the cleaning solution.

14. A method of preserving a cleaning composition comprising the steps of combining a short chain (Ci to Ce), unsaturated, organic acid or salt thereof having at least two carboxyl groups, wherein the short chain unsaturated organic acid is itaconic acid or salt thereof, with a nonionic surfactant.