IRRITATION MITIGATING SURFACTANTS

Abstract

Use of a furan-based surfactant in a detergent for reducing or preventing irritancy during use.

Claims

1-11. (canceled)

12. A method for treating a substrate comprising: forming a wash liquor comprising a detergent composition and water; and applying the wash liquor to the substrate, wherein the wash liquor comprises from 0.1 to 5 g/l of a furan-based surfactant.

13. The method according to claim 12, wherein the furan-based surfactant comprises a head group, a furan and a hydrophobic group connected to the furan by a linker.

14. The method according to claim 13, wherein the head group is selected from beta sulphonate, beta hydroxy sulphonate, beta sulphate, beta hydroxy sulphate, alpha sulphonate, alpha hydroxy sulphonate, alpha sulphate, alpha hydroxy sulphate, and mixtures or combinations thereof.

15. The method according to claim 13, wherein the linker is selected from a direct alkyl, carbonyl alkyl, hydroxy alkyl, carbonyl ether, hydroxy ether, carbonyl amide, hydroxy amide and ester, and mixtures or combinations thereof.

16. The method according to claim 13, wherein the hydrophobic group is a C10-C20 hydrophobic group.

17. The method according to claim 13, wherein the hydrophobic group is a linear alkyl chain comprising about 12-18 carbon atoms.

18. The method according to claim 12, wherein the wash liquor comprises from 0.1 to 2 g/l of the furan-based surfactant.

19. The method according to claim 12, wherein the detergent composition is a hand wash laundry detergent.

20. The method of claim 19, wherein the wash liquor comprises from 1 to 2 g/l of the furan-based surfactant.

21. The method according to claim 12, wherein the detergent composition is a hand dishwash detergent.

22. The method according to claim 12, wherein the detergent composition is a hard surface cleaner.

Description

EXAMPLES

[0337] The following are methods for making the furan-based surfactants described herein and using the various different linker groups described. For each example the order of steps may be interchangeable and alternative reagents may provide the most optimal conditions.

[0338] Direct Alkyl

[0339] Starting with chloromethyl furan the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0340] The Friedel-Crafts alkylation of the sulphonated furan using the corresponding alkyl halide yields the directly alkylated furan using a strong Lewis acid e.g. aluminium chloride as catalyst.

[0341] Exemplar Structures

##STR00010##

[0342] Carbonyl Alkyl

[0343] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0344] The Grignard reaction of an alkyl magnesium halide with the aldehyde moiety of the furfural yields the 2° alcohol. This is then oxidised in a second step to produce the carbonyl alkyl derivative. A solution of the Grignard reagent is prepared from the alkyl bromide and magnesium in dry solvent. The furfural is added with cooling. The resulting reaction mixture is quenched, and the hydroxyalkyl derivative is extracted and dried. The subsequent oxidation with manganese dioxide yields the product in 4 hrs with heating.

[0345] Exemplar Structures

##STR00011##

[0346] Hydroxy Alkyl

[0347] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0348] The Grignard reaction of an alkyl magnesium halide with the aldehyde moiety of the furfural yields the 2° alcohol. A solution of the Grignard reagent is prepared from the alkyl bromide and magnesium in dry solvent. The furfural is added with cooling. The resulting reaction mixture is quenched, and the product extracted and dried.

[0349] Exemplar Structures

##STR00012##

[0350] Carbonyl Ether

[0351] The linear and branched carbonyl ether derivatives are prepared from chloromethyl furfural following the typical 4-step route and methodology described below. The acid chloride is reacted with the appropriate alcohol to form the carbonyl ether. The sulphonation is achieved via a Strecker reaction.

##STR00013##

[0352] Example for sodium (5-((tetradecan-2-yloxy)carbonyl) furan-2-yl)methanesulfonate

[0353] General Procedure—Step 1: 5-(Chloromethyl)furfural (25.0 g, 172.9 mmol) and tert-butyl hypochlorite (93.35 g, 859.8 mmol, 5 eq) were vigorously stirred at room temperature for 24 hrs. The volatiles were evaporated at room temperature under reduced pressure to afford the crude product, 5-(chloromethyl)furan-2-carbonyl chloride (CMFCC) (38 g, 72% yield by .sup.1H NMR spectroscopy). This product was used in subsequent reactions as a crude mixture of calculated purity.

[0354] General procedure—Step 2: CMFCC (62% CMFCC w/w, 5.9 g, 33.3 mmol) was added to 2-tetradecanol (ROH), (10.72 g, 50 mmol, 1.5 eq). The mixture was stirred overnight at 50° C. (ensuring solid alcohols were melted), under a dry atmosphere until complete reaction was determined by TLC. Excess alcohol may be removed under high vacuum, the resulting dark residue was purified by column chromatography (silica gel, ethyl acetate:hexanes (1:9), Rf=0.24) to afford the furan ester as a yellow oil (7.65 g, 64% yield).

[0355] General Procedure Step—3: A flask was charged with the alkyl chloride (2.0 g, 5.6 mmol), sodium iodide (1.7 g, 1.1 mmol, 2 eq) and acetone (20 ml). The system was brought to reflux and stirred for an hour. Thereafter, the solution was filtered through a short path of Celite. The solvent was evaporated from the filtrate under reduced pressure. The resulting orange residue was triturated with ethyl acetate (50 ml), filtered through Celite. The resulting solution was washed with sodium metabisulfite solution (10% w/w in water, 2×50 ml), water (50 ml) and brine (50 ml). The combined organic phases were dried (MgSO.sub.4), filtered and evaporated to afford the alkyl iodide furan as a yellow solid (2.3 g, 93%).

[0356] General Procedure—Step 4: A flask was charged with the methyliodide furan ester (9.28 g, 20.69 mmol), sodium sulfite (3.91 g, 31.04 mmol, 1.5 eq), tetrabutylammonium iodide (764.4 mg, 2.07 mmol, 0.1 eq) and acetonitrile/water mixture (1:1, v:v; 50 ml). After stirring at 80° C. for 10 hrs, the solvent was removed, and the resulting product was extracted with methanol (100 ml) with sonication at 50° C. for 5 min. The supernatant was obtained from the resulting suspension after centrifugation (3500 rpm, 5 min). Methanol extraction of the residue was repeated twice. The combined methanol fractions were evaporated to dryness and the resulting solid was washed with ethyl acetate (100 ml) and collected via filtration to afford the sodium salt as white solid (5.5 g, 57% yield).

[0357] Exemplar Structures

##STR00014##

[0358] Carbonyl Amide

[0359] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0360] Oxidise the aldehyde group through to a carboxylic acid or form the acid chloride moiety. The corresponding alkylamine is then reacted directly with the acid chloride or with the acid using coupling chemistry e.g. N,N′-carbonyldiimidazole (CDI) and alkylamine.

[0361] CDI is added to a stirred suspension of furan acid (until the evolution of gas subsides). The amine is added and the reaction stirred overnight. The product is extracted and purified by chromatography.

[0362] Exemplar Structures

##STR00015##

[0363] Ester

[0364] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0365] First reduce the aldehyde moiety of furfural to form the hydroxyl methyl functionality using sodium borohydride. Then in a second step esterify the hydroxymethyl furan using the corresponding alkyl acid (plus coupling agent) e.g. CDI or the alkyl acid chloride with cooling in dichloromethane (with triethylamine).

[0366] Exemplar Structures

##STR00016##

[0367] Ether (Adjacent to the Furan Ring)

[0368] Using chloromethyl furan as the starting material. The ether linked alkyl chain can be prepared by bromination of the furan ring (e.g. using N-bromosuccinimide or bromine) followed by a reaction with the hydroxyalkanewith titanium isopropoxide in refluxing toluene.

[0369] The product is then sulphonated via the Strecker reaction using sodium sulfite.

[0370] Exemplar Structures

##STR00017##

[0371] Ether (1 C Removed from the Furan Ring)

[0372] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0373] Starting with chloromethyl furfural, the aldehyde moiety is first reduced through to the hydroxymethyl furan using sodium borohydride. In a second step this alcohol is deprotonated with a strong base e.g. sodium hydride to form the alkoxide which is trapped with the appropriate alkyl bromide.

[0374] Exemplar Structures

##STR00018##

[0375] Hydroxy Ether

[0376] Starting with chloromethyl furfural the sulphonated headgroup is introduced via sodium sulphite using a Strecker reaction.

[0377] The furfural is then reacted with the hydroxyalkane (which may need to be activated as the alkoxide) to yield the product.

[0378] Exemplar Structures

##STR00019##

[0379] Hydroxy Amine

[0380] The carbonyl amide described previously may be selectively hydrogenated with the appropriate catalyst.

[0381] Exemplar Structures:

##STR00020##

[0382] Materials

[0383] The following materials were used to demonstrate efficacy of the claimed furan-based surfactants: [0384] C12LEFS-C12 Linear Ester Furan Sulphonate [0385] C14LEFS-C14 Linear Ester Furan Sulphonate [0386] C12GEFS-C12 Guerbet Ester Furan Sulphonate [0387] C14MEFS-C14 Methyl Ester Furan Sulphonate

[0388] Images below are in the same order as the names/abbreviations above.

##STR00021##

[0389] Mildness

[0390] The mildness of the surfactants was tested by a colorimetric assay of their solubilisation of zein (corn protein) mixed with a blue dye and dried to the bottom of a 96 well plate, the greater the solubility the greater the Absorbance.

[0391] Measurements were made at 10, 5 & 1 g/I, SDS was used as a positive control (harsh) and Rhamnolipid (RL) and Water were used as negative controls (mild).

[0392] The concentrations of furan surfactant reflect the normal levels one might use in a detergent composition up to and over the normal level used. The use of 10 g/I is included as a parameter stretch and not a realistic amount used in a detergent.

[0393] Of all the detergents considered for furan surfactant, hand wash detergents are the most concentrated in use with around 1 to 2 g/I total detergent typically used in a wash liquor.

[0394] Samples were mixed, incubated at 40C for 30 minutes with agitation then read at 590 nm on a UV-Vis spectrophotometer.

[0395] FIGS. 1, 2 and 3 illustrate the improved mildness behaviour exhibited by furan-based surfactants.