GB2528693A

GB2528693A - Detergent formulation

Info

Publication number: GB2528693A
Application number: GB1413368.0A
Authority: GB
Inventors: Perrine Ducrocq; Jennifer Cazes; Vanessa Sors; Dirk Veryser; Colin Litten-Brown
Original assignee: Robert McBride Ltd
Current assignee: Robert McBride Ltd
Priority date: 2014-07-29
Filing date: 2014-07-29
Publication date: 2016-02-03
Also published as: GB201413368D0

Abstract

A detergent formulation for removing organic soils, comprising the following surfactants at the following relevant weight concentrations with respect to their total weight: (i) 24-26% of an amine oxide, (ii) 11-13% of a betaine, and (iii) 62-64% of a blend of (a) an alpha-olefin sulfonate or an alkyl sulfonate with (b) an alkyl ether sulfate. The relative weight ranges for the blend constituents are 8-70%, preferably 10-50%, for the sulfonate part and 30-92%, preferably 50-90%, for the sulfate part. The amine oxide is preferably a coco amido alkyl more preferably propyl amine oxide. Likewise, the betaine is preferably a coco amido alkyl more preferably propyl betaine. Furthermore, the sodium salts of the sulfonate and sulfate parts are preferred. The detergent composition has a pH of 6.5-8.5, preferably 7.5. It is particularly suitable for the removal of burnt food matter from metal, wood, glazed ceramic, plastic, glass and PTFE surfaces.

Description

DETERGENT FORMULATION

Field of the invention

The present invention relates to detergent base formulations and detergent formulations comprising such base formulations for the removal of organic soils. The present invention relates more particularly to a detergent base formulations and compositions for the removal of hydrated and temperature-dehydrated organic soils from rigid surfaces such as metal, wood, glazed ceramic, plastic, glass and PTFE.

Organic soils may be lipidic, proteinaceous, carbohydrate-based or a combination of the above and may also contain a mineral content or other organic substances. Soils derived from materials intended for human consumption may range from simple materials to complex mixtures.

Specifically it refers to the use of formulations that are used in diluted form and intended for use without automatic or mechanical augmentation of the decontamination process.

Many objects are used in the preparation and consumption of food products and these objects, which can be constructed from a variety of materials and in a variety of shapes can become contaminated with the food product being prepared or consumed.

While the contamination may be easy to remove under normal decontamination processes if the contaminated surface has been subjected to heat then the organic material may be dehydrated or chemically altered / burnt in such a way that its adherence to the surface is increased.

Formulations for the removal of such soils are well known and widely used in the domestic environment in a non-mechanical manual process.

Such formulations commonly contain anionic surfactants and these can be selected from a wide range of options but generally the bulk feed-stock of the surfactants will derive from either natural or synthetic! petrochemical sources.

Anionic surfactants are also available from a variety of suppliers with many of the specific grades of surfactant being offered by multiple suppliers and others being offered by only a few.

In recent years the fluctuations in the price of petrochemicals and thus the bulk feed stocks have meant that the price of anionic surfactants has varied widely. This can mean that during one part of the year materials derived from natural feed-stocks are cheaper than those derived from petrochemical I synthetic sources whereas in another part of the year the natural-derived surfactants are more expensive.

As well as rapid variability in the relative price of natural versus synthetic-derived surfactants there can also be variability in the availability of materials from individual suppliers as over-demand from other customers uses up short-term stocks.

When manufacturing any kind of decontaminant formulation it is normal that the precise breakdown of the formulation is fixed, that there are commercial deals with preferred' suppliers who have been validated for quality and that the price of the formulation and expected decontaminant properties are pre-defined and fixed.

The process of introducing a new formulation is time-consuming and often involves time-scales that are greater than the micro-fluctuations in surfactant price and availability and thus there is usually no possibility to re-formulate in response to such changes.

The result in short-term fluctuations in surfactant price can mean that a product with a fixed selling price, whether that is to a distributor, retailer or direct to the end consumer generates less profit if the cost of goods increases.

What is needed is a flexible formulation that can be quickly adjusted in production within certain specifications but which has no significant impact on decontaminant performance and hazard / safety classification. This would allow the manufacturer to adjust the ratio of anionic surfactants in reaction to fluctuations in price to act as a buffer in the cost of the formulation and maintain a constant evel while at the same time maintaining a pre-determined level of performance.

It is an object of the present invention to obviate or mitigate the abovementioned disadvantages.

Summary of the Invention:

According to a first aspect of the present invention there is provided a detergent formulation for the removal of organic soils, the formulation comprising the following surfactants: (i) 24-26 wt% of an amine oxide surfactant, (H) 11-13 wt% of a betaine surfactant, and (Hi) 62-64 wt% in total of a blend of (a) alpha olefin sulphonate or a alkyl sulphonate, and (b) an alkyl ether sulphate, the weight percentages being based on the total weight of surfactants (i), (H), and (Hi).

In all cases the relative amounts refer to 100% of each respective component, whereas in practice suitable materials may be sourced in dilute form so the inclusion level of the surfactant as purchased would need to be adjusted depending on the active level.

The ratio of the surfactants in the blend can be adjusted within certain levels to allow equivalent product performance but flexibility with respect to formulation costs depending on fluctuations of the relative prices of the two anionic surfactants.

The adjustment in the level of the surfactants in the blend is also such that it does not result in any alteration in the classification of the formulation from the point of view of safety labelling.

The blend preferably comprises 8-70 wt% alpha olefin sulphate or alkyl sulphonate and 30-92 wt% alkyl ether sulphate based on the total weight of the blend.

More preferably, the blend comprises 10-50 wt% alpha olefin sulphate or alkyl sulphonate and 50-90 wt% alkyl ether sulphate.

Preferably the detergent formulation comprises 62.75-63.25 wt% of the blend; 24.4-24.8 wt% of the amine oxide surfactant; and/or 12.1-12.5 wt% of the betaine surfactant based on the total weight of surfactants (i), (H), and (iii).

The betaine surfactant is preferably of the general formula I:

R N

H

in which: ft is a C320 alkyl group (preferably C13.12); and xis 1-4 (preferably 3); R2 is a C13 alkyl group (preferably methyl); and R3 is a C13 alkyl group (preferably methyl).

R2 and R3 may be the same as one another, or may be different. Such compounds of general formula I above are typically produced from reactions involving naturally derived substrates (such as fatty acids derived from coconuts, which are incorporated in part as the ft group above). As a result, the betaine surfactant may be present as a mixture of compounds of the general formula I above, in which ft may have a range of values. The preferred betaine surfactant for use in the present invention is coco amido propyl betaine (of the general formula I above in which ft is C10.12, x is 3, and both F{2 and 1% are methyl).

The amine oxide surfactant is of the general formula II: RLNkN( in which: R4 is a C320 alkyl group (preferably C1012); and y is 1-4 (preferably 3); R5 is a C3 alkyl group (preferably methyl); 1% is a C13 alkyl group (preferably methyl); and represents a dative bond.

Again, R5 and R5 may be the same as one another, or may be different. As with the products of general formula I, compounds of general formula II above are also typically produced from reactions involving naturally derived substrates (such as fatty acids derived from coconuts, which are incorporated in part as the R4 group above).

As a result, the amine oxide surfactant may be present as a mixture of compounds of the general formula II above, in which R4 may have a range of values. The preferred amine oxide surfactant for use in the present invention is coco amido propyl amine oxide (of the general formula II above in which R4 is C1012, y is 3, and both R5 and R6 are methyl).

The alkyl group of the alkyl sulphonate is preferably a C1220 alkyl group, more preferably a C1417 alkyl group. The alkyl sulphonate is preferably a sodium alkyl sulphonate.

The alkyl group of the alkyl ether sulphate is preferably a lauryl (C2 alkyl) group.

The ether is preferably 2E0 or 3E0. The alkyl ether sulphate is preferably a sodium alkyl ether sulphate.

The detergent formulation may comprise a total of 5-50 wt% of surfactants (i), (H), and (Hi) and 50-95 wt% water based on the total weight of the detergent formulation. Preferably, the formulation may comprise 5-40 wt% (more preferably 8-wt%) of surfactants (i), (H), and (Hi) based on the total weight of the detergent formulation.

The formulation may comprise a total of at least 95 wt% of surfactants (i), (H), and (Hi) based on the total weight of the detergent formulation.

According to a second aspect of the present invention there is provided a method of cleaning a soiled substrate, the method comprising applying the formulation according to the first aspect of the invention to a substrate. The method may further comprise a step of rinsing the substrate after application of the formulation.

The detergent formulation may further comprise one or more viscosity modifiers (preferably thickeners, sodium chloride and/or ethanol), dyes, foam modifiers (preferably polymeric foam modifiers), fragrances, preservatives, pH adjusters (preferably sodium hydroxide and/or citric acid), chelating agents and/or biocides.

The detergent formulation preferably has a pH of 6.5 -8.5, more preferably about 7.5.

The total amount of base added to the final formulation can range from 5% total active matter to 40% total active matter, the remainder of the formulation being composed of water and optional viscosity modifying agent (such as thickener, sodium chloride, ethanol or any other viscosity modifier), foam modifier (for example various polymers), dye, fragrance, pH adjuster (such as sodium hydroxide or citric acid), chelating agents, biocides and preservative. Preferably the formulation would have a pH of 7.5± 1.0.

The anionic surfactant alpha olefin sulphonate will subsequently be referred to as AOS and the other anionic surfactant alkyl ether sulphate will subsequently be referred to as AES.

It has surprisingly be found that the ratio of AOS to AES within the formula can be changed from 8% AOS 92% AES to a ratio of 70% AOS to 30% AES with no significant impact on performance within a formulation at the same total active level.

The preferred ratios of the two anionic surfactants are either 10% AOS 90% AES or 50% AOS: 50% AES.

The ratio of AOS to AES can be varied depending on the relative purchase price of each of the two surfactants to maintain uniform inclusion costs of the total anionic component of the formulation whilst maintaining the same level of decontaminant removal towards hydrated and temperature-dehydrated organic soils.

It is preferred that such formulations have a total active content of between 8% -30%.

Thus, the preferred range of surfactants in the flexible formulation can be given for any desired level of total active material (TAM) in the preferred base active formulation where the TAM is between 5-50% as: E Amine oxide surfactant + betaine surfactant + Total anionic surfactant Where for a composition with the ratio of non-ionic surfactant amphoteric surfactant total anionic surfactant of A B C where A, B and C are expressed as percentages and total 100:

TAM

Amine oxide surfactant content in final formulation = ______ X A

TAM

Betaine surfactant content in final formulation = ______ X B

TAM

Total anionic surfactant content in final formulation = ______ X C And further where for a desired ratio of AOS (RAOS) to the ratio of AES (100-RAOS) the amount of each surtactant (i.e. the relative proportions of the two materials within the total anionic surfactant content in the final formulation) is: Total AOS content TAM / RAOS = XI X C in final formulation 100 100 Total AES content TAM (100RAOS) = Xk XC in final formulation 100 100 It is also possible to replace the alkyl olefin sulphonate with sodium paraffin sulphonate though the use of alkyl olefin sulphonate is preferred.

Further features of the invention are defined in the appended claims and appendix.

Examples:

The formulations are evaluated by means of a standard method where ceramic sheets are artificially soiled with a pre-made lipidic soil and then the test formulations used to remove the soil by means of the method described below: The proteinaceous / lipidic soil used contains a lipidic mixture which is composed of equal parts of beef tallow, coconut fat, butter, olive oil, sunflower oil, lard and margarine which are heated together in a beaker at 60°C and mixed together before being divided and stored in portions of 289g.

For the soil composition 450g of demineralised water is heated to 60CC and to this 50g of milk powder and stir for one minute. Once the milk powder has dispersed 170g of flour is added and again the mixture is stirred for one minute to mix the flour in uniformly. Next, one 289g portion of the lipidic mixture is added and allowed to disperse with mixing for one minute. Finally, 41g of cream is added and the mixture is given a final mix for one minute before being stored at 60CC for one hour prior to use.

Test ceramic plates are heated for one hour at 60°C after which 3.00g ±0.05g of the soil is placed in the middle of the plate by means of a pipette and allowed to flow such that it covers the middle of the plate evenly.

The test plates are stored in a refrigerator for at least 12 hours and removed from the refrigerator at least 10 minutes prior to use.

A semi-automatic dishwasher machine (SAD) is used to ensure uniform cleaning of plates. The device comprises a brush which is thoroughly cleaned prior to use in a neutral detergent with care taken not do disrupt the bristles.

To 5 litres of hard water at 50°C is introduced into the SAD and 2.0000g ±0.0005g of the test formula is added. Foam is generated using a pump running for 30 seconds at a flow rate of 10 litres per minute.

The SAD is programmed so that the brush stirs for 15 seconds and then pauses for 15 seconds. The SAD is started and the first plate introduced into the holder. When the brush finishes stirring the plate is removed and replaced with another. The test is continued until the point where the foam collapses and the result quoted in terms of the number of plates that can be washed until this point.

Table 1 below shows the results for two different ratios of AOS and AES at eight different levels of total active matter (TAM) within the formulation. In all cases it can be seen that the number of plates that can be washed before the foam collapses is either the same or within an acceptable level of error similar. The figure far the number of plates is the average of a number of separate evaluations.

Thus, the total number of plates that can be effectively washed using this technique is dependent mainly on the total active matter within the formulation and not the relative proportions of AOS and AES allowing for flexibility within the formulation to vary these materials depending on raw material pricing and availability at any given moment in time.

Table 1 -Plate Wash Test Results Number of plates % TAM in Formula Ratio of AOS Ratio of AES washed 10 35

_________________ ________________ ________________ 50 34 10 41

13 _________________ ________________ ________________ 50 40 10 44

________________ _______________ _______________ 50 46 10 45

17 ________________ _______________ _______________ 50 46 10 47 18 ________________ _______________ _______________ 50 45 10 48

___________________ ___________________ ___________________ 50 48 10 50

23 ___________________ ___________________ ___________________ 50 51 10 60 28.5 50 61 An alternative test method uses a soil which has lipidic, carbohydrate and proteinaceous content which is dehydrated I burnt after application to a soil making removal under normal decontamination procedures more difficult than the conditions experienced in the plate wash test.

For this burnt soil test a soil is used which is composed of 8.46% margarine, 6.34% plain flour, 1.06 % instant coffee, 12.68% granulated sugar, 21.14% tomato ketchup, 6.77% egg yolk and 43.55% water. These ingredients are mixed together until homogenous.

The substrate used are rectangular Pyrex dishes onto which lOg of soil is evenly applied with a brush across the base of the dish ensuring as far as possible even coverage. The dish is then placed in an oven at 200°C for 10 minutes to bake the soil before being removed and stored at room temperature for 2 hours to cool.

For the test, Bog of test formulation is applied evenly over the burnt soil and the dish is placed in a large bowl and 5 litres of water at 50°C poured over the dish. The diluted formulation is allowed to soak for 15 minutes after which time the dishes are moved laterally within the dilute formulation for 1 minute to introduce a degree of gentle agitation.

The dish is then removed from the dilute formulation and dipped in clean water five times to remove any excess soil before being left to dry for at least 12 hours.

Soil removal is assessed by expert panellists on a scale of 0-10 where 0 represents no soil removal and 10 represents complete soil removal. The test is repeated at least in triplicate.

Under such test conditions the performance of the 90:10 and 50:50 anionic ratios are similar and the level of soil removal is proportional to the total active matter content of the formulation with greater soil removal seen at greater total active matter content.

APPENDIX

Emboctments of the invention will now be described in the following paragraphs.

1. A formulation for the removal of organic soils from articles used in food preparation and consumption in a non-mechanised process in which the formulation is composed of a base active formulation containing 24-26% (with a preferred amount of 24.6%) of a non-ionic surfactant, 11-13% (with a preferred amount of 12.3%) of an amphoteric surfactant and 62-64% (with a preferred amount of 63.1%) in total of a blend of two anionic surfactants.

2. A formulation as described in embodiment 1 where the two anionic surfactants are preferably alpha olefin sulphonate and sodium alkyl ether sulphate.

3. A formulation as described in embodiment 1 where the non-ionic surfactant is preferably coco amido propyl amine oxide 4. A formulation as described in embodiment 1 where the amphoteric surfactant is preferably coco amido propyl betaine.

5. A formulation as described in embodiments 1 and 2 where the ratio of alpha olef in sulphate to sodium alkyl ether sulphate is between 8% alpha olefin sulphate: 92% sodium alkyl ether sulphate to a ratio of 70% alpha olef in sulphate to 30% sodium alkyl ether sulphate.

6. A formulation as described in embodiment 5 where the ratio of alpha olefin sulphate to sodium alkyl ether sulphate can be adjusted with no drop in decontaminant-removal performance.

7. A formulation as described in embodiment 1 where the total active matter level of total surf actant content is between 5 and 40%.

6. A formulation as described in any one of embodiments 1 to 7 where the bulk of the formulation is composed of water and can optionally contain viscosity modifiers, dyes, foam modifiers, fragrance, preservative, pH adjusters, chelating agents or biocide.

9. Formulations for the removal of hydrated and temperature-dehydrated organic soils from rigid surfaces such as metal, wood, glazed ceramic, plastic, glass and PTFE in which the formulation contains in addition to a primary non-ionic surfactant and a primary amphoteric surfactant two secondary anionic surfactants, the ratio of which can be adjusted from 50:50 of surfactant A to surf actant B to a ratio of 90:10 surfactant A to surfactant B with any combination in between while maintaining the same contaminant-removal properties.

Claims

CLAIMS: 1. A detergent formulation for the removal of organic soils, the formulation comprising the following surtactants: (i) 24-26 wt% of an amine oxide surfactant, (ii) 11-13 wt% of a betaine surfactant, and (Hi) 62-64 wt% in total of a blend of (a) alpha olefin sulphonate or a alkyl sulphonate, and (b) an alkyl ether sulphate, the weight percentages being based on the total weight of surfactants (i), (ii), and (Hi).
2. The detergent formulation as claimed in claim 1 wherein the blend comprises 8-wt% of the alpha olefin sulphate or alkyl sulphonate, and 30-92 wt% of the alkyl ether sulphate based on the total weight of the blend.
3. The detergent formulation as claimed in claim 2 wherein the blend comprises 10-50 wt% of the alpha olefin sulphate or alkyl sulphonate and 50-90 wt% of the alkyl ether sulphate based on the total weight of the blend.
4. The detergent formulation as claimed in any one of claims 1 to 3 comprising 62.75-63.25 wt% of the blend based on the total weight of surfactants (i), (H), and (Hi).
5. The detergent formulation as claimed in any one of claims 1 to 4 comprising 24.4-24.8 wt% of the amine oxde surfactant based on the total weight of surfactants (i), (H), and (Hi).
6. The detergent formulation as claimed in any one of claims 1 to 5 comprising 12.1-12.5 wt% of the betaine surfactant based on the total weight of surfactants (i), (H), and (iii).
7. The detergent formulation as claimed in any one of claims 1 to 6 wherein the betaine surfactant is coco amido alkyl betaine.
8. The detergent formulation as claimed in claim 7 wherein the coco amido alkyl betaine surfactant is coco amido propyl betaine.
9. The detergent base formulation as claimed in any one of claims 1 to 8 wherein the amine oxide surfactant is coco amido alkyl amine oxide.
10. The detergent base formulation as claimed in claim 9 wherein the coco amido alkyl amine oxide surfactant is coco amido propyl amine oxide.
11. The detergent base formulation as claimed in any one of claims 1 to 10 wherein the alkyl sulphonate is a sodium alkyl sulphonate.
12. The detergent base formulation as claimed in any one of claims 1 to 11 wherein the alkyl ether sulphate is a sodium alkyl ether sulphate.
13. The detergent formulation as claimed in any one of claims 1 to 12 comprising a total of 5-50 wt% of surfactants (i), (ii), and (Hi) and 50-95 wt% water based on the total weight of the detergent formulation.
14. The detergent formulation according to claim 13 comprising 5-40 wt% of surfactants (i), (U), and (Hi) based on the total weight of the detergent formulation.
15. The detergent formulation according to claim 14 comprising 8-30 wt% of surfactants (i), (ii), and (Hi) based on the total weight of the detergent formulation.
16. The formulation as claimed in any one of claims 13 to 15 further comprising one or more viscosity modifiers (preferably thickeners, sodium chloride and/or ethanol), dyes, foam modifiers (preferably polymeric foam modifiers), fragrances, preservatives, pH adjusters (preferably sodium hydroxide and/or citric acid), chelating agents and/or biocides.
17. The formulation as claimed in any one of claims 13 to 16 having a pH of 6.5 -8.5.
18. The formulation as claimed in any one of claim 17 having a pH of about 7.5.
19. The formulation as claimed in any one of claims ito 12 comprising a total of at least 95 wt% of surfactants (i), (H), and (Hi) based on the total weight of the detergent formulation.
20. A method of cleaning a soiled substrate, the method comprising applying the formulation according to any preceding claim to the substrate.
21. The method of claim 20, further comprising rinsing the substrate after application of the formulation.
22. The method according to claim 20 or 21, wherein the formulation applied is as claimed in any one of claims 13 to 18.