AU647681B2

AU647681B2 - Detergent compositions

Info

Publication number: AU647681B2
Application number: AU28546/92A
Authority: AU
Inventors: Johannes Hendrikus Maria Akkermans; Andrew Paul Chapple; William Derek Emery; Huig Euser; Michael Hull; Christophe Joyeux; Peter Cory Knight; Petrus Leonardus J. Swinkels
Original assignee: Unilever PLC
Current assignee: Unilever PLC
Priority date: 1991-11-26
Filing date: 1992-11-20
Publication date: 1994-03-24
Anticipated expiration: 2012-11-20
Also published as: ES2117969T3; PL296731A1; HK1014263A1; MX9206809A; HU216145B; NO302621B1; AU2854692A; CA2083331C; ATE166667T1; DE69225679T2; NO924557D0; CZ349592A3; MY109102A; CN1035066C; CN1073713A; NZ245202A; SK349592A3; EP0544492A1; JPH0739599B2; IN177823B

Abstract

A particulate high-density detergent composition having excellent flow properties comprises 15 to 50 wt% of a high-performance surfactant system - selected ethoxylated alcohol nonionic surfactant plus optionally a minor amount of primary alkyl sulphate - and from 20 to 60 wt% of zeolite. The ethoxylated nonionic surfactant preferably has a peaked ethoxylation distribution, and the zeolite may advantageously be maximum aluminium zeolite P. The composition is preferably prepared by an agglomeration process utilising a high-speed mixer/granulator.

Description

1 C3431 e '"DETERGENT COMPOSITIONS TECHNICAL FIELD The present invention is concerned with particulate detergent compositions that combine exceptionally good cleaning performance with high bulk density and excellent powder properties. The compositions contain a high 10 level of high-performance organic surfactant selected ethoxylated alcohol oip4s y plus am-nfAtA amount of alkyl sulphate and zeolite detergency builder, and are preferably prepared by an agglomeration process using a high-speed mixer/granulator.

BACKGROUND

Recently the trend in detergent powders has been towards increased bulk density, for example, above 600 g/l. These high-density or "concentrated" powders have been prepared by various processes, some involving post-densification of a spray-dried powder, and others based on dry mixing, agglomeration or other wholly non-tower processes.

2 C3431 The move to higher densities, and thus inherently less porous particles, has made the incorporation of high levels of mobile organic ingredients without loss of powder flow properties more difficult. However, it has become highly desirable to improve detergency performance by incorporating higher levels of surfactant, and by using surfactants having the greatest possible effectiveness against oily and fatty soils. One class of such surfactants consists of ethoxylated alcohols 10 having a relatively low degree of ethoxylation, and those are generally mobile liquids at ambient temperature.

In view of increasing environmental awareness, it has also become desirable to use alkyl sulphates in preference to the linear alkylbenzene sulphonates traditionally used in laundry detergents. Alkyl sulphates are readily biodegradable and can be obtained from renewable sources such as coconut and palm oil.

However, they are generally more difficult to process 20 into high quality detergent powders than are alkylbenzene sulphonates.

Nonionic surfactants, alkyl sulphates and mixtures of the two have been found to provide highly efficient detergency, but because of their mobility are difficult to incorporate, even at moderate levels, into free-flowing powders that will disperse in the wash liquor. When higher proportions of these surfactants are required in order to push detergency performance to ever higher levels, these difficulties would be expected to increase, and to be exacerbated even furth r In the highly concentrated, dense powders currently favoured by the consumer and the detergents industry.

3 C3431 The present inventors, however, have succeeded in formulating high bulk density free-flowing detergent powders combining excellent performance with good powder properties and dispersibility, despite their containing relatively high levels of high-performance mobile surfactants. The powders of the invention contain relatively high levels of zeolite builder, and may be prepared by a granulation process in a high-speed mixer/granulator. Especially good powder properties may 10 be obtained by use of a novel zeolite P as the builder; "and especially good detergency may be obtained by use of selected nonionic surfactants.

PRIOR ART S'.EP 265 203A (Unilever) discloses a surfactant blend mobile at a temperature within the range of from 20 to 80 C, comprising from 20 to 80 wt% of alkylbenzene sulphonate or alkyl sulphate, from 80 to 20 wt% of ethoxylated nonionic surfactant and from 0-10 wt% water.

The surfactant blend may be sprayed on to an absorbent particulate solid material, for example, spray-dried polymer-modified Burkeite, to give free-flowing detergent powder containing up to about 25 wt% of surfactant.

EP 436 240A (Unilever) discloses a similar mobile surfactant blend additionally containing a fatty acid soap. When sprayed onto an absorbent solid material, this blend gives powders having improved flow and dispensing properties.

GB 1 462 134 (Procter Gamble/Collins) discloses linear or predominantly linear ethoxylated primary alcohols of closely defined chain length, chain length distribution, ethylene oxide content, ethoxylation 4 C3431 AU(1) distribution and free alcohol content. These materials give improved oily soil detergency as compared with conventional commercially available materials.

EP 133 715A (Union Carbide) discloses an alkoxylation product mixture having an especially highly peaked distribution of alkoxylation species, in which a single prevalent alkoxylation species constitutes 20 to wt% and the amounts of species differing substantially from the prevalent species are strictly limited.

EP 384 070A (Unilever) discloses the use as a detergency builder of zeolite P having a silicon to aluminium ratio not greater than 1.33 (zeolite MAP).

This zeolite has been found to be a more effective and rapid binder of calcium ions than is conventional zeolite 4A.

EP 521 635A (Unilever), published on 7 January 1993, discloses free-flowing particulate detergent compositions based on zeolite MAP and containing high levels of liquid, viscous-liquid, oily or waxy components (for example, nonionic surfactants) while displaying excellent flow properties.

Example K of that application discloses a high bulk density powder consisting of 50 wt% zeolite 4A, 23.4 wt% sodium carbonate, and 26.6 wt% of the nonionic surfactant Synperonic A3 (synthetic C 12 1 5 alcohol having an average degree of ethoxylation of and Example 7 discloses a high bulk density powder consisting of 56.6 wto zeolite MAP, 13.3 wt% sodium carbonate, and 30.1 wt% Synperonic A3. These compositions are specifically disclaimed in the present application.

A

A~ A 4/1- Ar 5 C3431 AU(1) EP 544 635A (Unilever), with which the present application shares a common priority, claims a process for preparing a granular detergent composition having a bulk density of at least 650 g/l, which comprises treating a particulate starting material in a high speed mixer/densifier in the presence of a liquid surfactant composition comprising an alkyl sulphate (20-80 an ethoxylated nonionic surfactant (80-20 wt%) and water (0-20 wt%).

DEFINITION OF THE INVENTION The present invention provides a ,..ticulate detergent composition having a bulk density of at least 650 g/l, preferably at least 700 g/l and advantageously at least 800 g/l, comprising: from 15 to 50 wt% of a surfactant system consisting 20 essentially of: *e ethoxylated nonionic surfactant which is a primary C 8

-C

18 alcohol having an average degree of ethoxylation not exceeding 6.5 (from 60 to 25 95 wt% of the surfactant system), and (ii) primary C 8

-C

18 alkyl sulphate (from 5 to 40 wt% of the surfactant system); 30 from 20 to 60 wt% of zeolite, optionally other detergent ingredients to 100 wt%.

SVzT Q9> 6 C3431 AU(1) DETAILED DESCRIPTION OF THE INVENTION The particulate detergent composition of the invention is characterised by an especially high level of a high-performance organic surfactant system. At least wt% of the composition is constituted by the surfactant, and as much as 50 wt% may be present.

Compositions may advantageously contain at least 20 wt%, more advantageously at least 25 wt%, of the surfactant system.

The surfactant system consists essentially of ethoxylated alcohol having a relatively low degree of ethoxylation, with a lesser proportion (not exceeding 40 wt% of the surfactant system) of primary alkyl sulphate.

The proportion of primary alkyl sulphate preferably does not exceed 35 wt% (of the surfactant system), and 20 more preferably does not exceed 30 wt% of the surfactant system. Preferred proportions of alkyi sulphate in the surfactant system are from 5 to 35 wt%, and advantageously from 10 to 30 wt%.

e 25 Also preferred are surfactant systems in which the proportion of alkyl sulphate does not exceed 15 wt%.

The ethoxylated alcohol nonionic surfactant The ethoxylated alcohol nonionic surfactant employed in the detergent compositions of the present invention has a relatively low degree of ethoxylation, not exceeding 7 C3431 AU(1) The ethoxylated alcohol preferably has an average degree of ethoxylation within the range of from 3 to The preferred range for the average degree of ethoxylation of the nonionic surfactant is within the range of from 4 to 6.5, more preferably from 4 to 6 and most preferably from 4 to A mixture of differently ethoxylated materials may be used, provided that the overall degree of ethoxylation meets the stated requirements.

The HLB value of the nonionic surfactant preferably does not exceed 11.0, and more preferably does not exceed 10.5. Desirably the HLB value is within the range of from 9.5 to 10.5.

The chain length of the ethoxylated alcohol may generally range from C 8 to C 18 preferably from C 12 to

C

1 6 an average chain length of C 1 2 1 5 is preferred.

20 Especially preferred is ethoxylated alcohol consisting wholly or predominantly of C 1 2

-C

1 4 material.

The ethoxylated alcohol is preferably primary, but secondary alcohol ethoxylates could in principle be used.

25 The alcohol is preferably wholly or predominantly straight-chain. Suitable alcohols are S.vegetable-derived, for example, coconut, which is the most preferred material. Among the synthetic alcohols, 0* Ziegler alcohols are preferred to oxo-based alcohols.

*o su~ 8 C3431 According to a preferred embodiment of the invention, giving exceptionally good oily soil detergency, the ethoxylated alcohol (which of course is always a mixture of species having different numbers of ethylene oxide units) is a "narrow range" material having a distribution of ethoxylated species that is more highly peaked about a single prevalent value than is the case in conventional commercial nonionic surfactants. The content of unethoxylated material is also generally 10 lower, and may be reduced further by so-called "stripping".

"Narrow range" alkoxylates are described and claimed, for example, in EP 133 715A (Union Carbide) mentioned previously.

These are especially highly peaked mixtures having an average alkoxylation number of at least 4, in which at least one alkoxylation species (the "prevalent species") 20 constitutes about 20 to 40 wt% of the mixture; the proportion of species having 3 or more alkoxylation units above the mean is less than 12 wt%; and the species having 1 more and 1 less alkoxylation unit that the mean are each present in a weight ratio to the prevalent species of 0.6:1 to 1:1. Preferred product mixtures contain from 80 to 95 wt% of alkoxylation species having alkoxylation numbers within plus or minus 2 of the mean.

However, the term "narrow range" as used in the present specification also covers materials that are not so highly peaked as to meet the requirements of the Union Carbide patent claims, but yet are substantially more peaked than, for example, the commercially available ICI "Synperonic" (Trade Mark) ethoxylated alcohols.

9 C3431 The term therefore is defined herein as covering any ethoxylated alcohol product in which a single ethoxylation species constitutes 13 wt% or more, preerably 15 wt% or more, of the product. Conventional ethoxylates contain no more than about 10 wt% of any one ethoxylation species. The prevalent species preferably contains 4 or 5 ethoxylation units.

Preferred "narrow range" ethoxylated alcohol used in 10 the compositions of the invention may have any one or more of the following characteristics: at least 20 wt% of the ethoxylated alcohol may be constituted by a single ethoxylation species; .I at least one ethoxylation species (hereinafter the prevalent species) may constitute from 20 to 40 wt% of the ethoxylated alcohol, the proportion of species having 3 or more ethoxylation units above the mean being less than 12 wt%, and the species having 1 more and 1 less ethoxylation unit than the mean each being present in a weight ratio to the prevalent species of 0.6:1 to 1:1; from 80 to 95 wt% of the ethoxylated alcohol may be constituted by ethoxylation species having ethoxylation numbers within plus or minus 2 of the mean.

Differently defined "narrow range" ethoxylates are also described in GB 1 462 132 (Procter Gamble/ Collins): these are materials having an average degree of ethoxylation between 3.5 and 6.5, the amount of material having a degree of ethoxylation within the 2-7EO range being at least 63 wt%, and the amount of free alcohol not exceeding 5 wt%. These materials are also 10 C3431 suitable for use in the compositions of the present invention.

The following table shows the ethoxylation distribution of some commercially available coconut-based ethoxylates, both narrow-range (NRE7, NRE5 etc), and broad-range (E7, E3), the figures indicating the nominal average degree of athoxylation in each case.

0 It is within the scope of the invention to achieve Sthe preferred value of 4 to 6.5 for the average degree of ethoxylation by using a mixture of commercial materials, eg a (nominal) 3EO ethoxylate and a (nominal) 7EO ethoxylate, in appropriate proportions.

S. However, it is especially preferred to use a single commercial material, and the materials designated NRE4.6 and NRE4.2 are especially preferred, NRE4.2 being particularly favoured.

It is especially preferred, in accordance with the invention, to use wholly or predominantly straight-chain ethoxylated alcohol that is also "narrow range".

It may also be desirable to use a "narrow range" ethoxylate having a narrower distribution of chain length than do conventional commerci-l nonionic surfactants.

For example, the nonionic surfactants described in the aforementioned GB 1 462 134 (Procter Gamble/Collins) are such that at least 65 wt% of the material has a chain length within 1 carbon atom of the mean value.

"Narrow range" ethlxylates are now commercially available in Europe and North America, for example, from Vista, Union Carbide and Hoechst.

-11-s C3431 C3431 vn A4 F^-r coco-based nonionic surfactants NR.E7 0 1 2 3 4 6 7 8 9 11 12 13-15 16-23 Mean EQ (peak*) Mean EQ (mol) 1.70 1.20 2.*45 4.65 7 .10 12.30 16.10 17.80* 16.30 11.70 6.00 2.05 0.55 7 NRE5 1.95 1.10 2.35 5.85 13.60 20.20 21. 10* 17.60 10.70 3.95 1.00 0.40 NRE4. 6 2.55 1.40 3.25 8.*00 16.05 20. 55* 20.25 15.85 8.60 2.60 0.65 0.35 NRE4 2 3.80 2.25 5.15 11.85 19.80 20. 85* 18.35 12.05 4.70 0.95 0.30 5 NRE3 8.40 5.50 12.30 22.*25 24.25* 14.45 9.25 2.85 0.30 3 4.15 2.70 3.80 4.*80 5.55 5.45 6.20 6.75 7.15 7.25* 7.20 7.00 6.60 15.00 10.25 15.05 10.95 12.50* 12.20 10.40 6.95 6.75 6.15 5.30 4.30 3.30 2.40 1.65 2.10 5.96 5.20 5.96 5.204.86 4.27 3.0168729 6.87 2.99 12 C3431 AU(1) The primary alkyl sulphate The primary alcohol sulphate (PAS) that may constitute from 5 to 40 wt% of the surfactant system, may have a chain length in the range of C- C 18 preferably C12-C16, with a mean value preferably in the C 12 1 range. Especially preferred is PAS consisting wholly or predominantly of C 1 2

-C

1 4 material.

If desired, mixtures of different chain lengths may be used as described and claimed in EP 342 917A (Unilever).

As for the ethoxylated alcohol, predominantly or wholly straight-chain material, is preferred. PAS of vegetable origin, and more especially PAS from coconut oil (cocoPAS) is especially preferred. However, it is also within the scope of the invw-tion to use branched PAS as described and claimed in EP 439 316A (Unilever).

S The PAS is present in the form of the sodium or potassium salt, the sodium 'salt generally being preferred.

The zeolite detercency builder The amount of zeolite builder in the compositions of the invention may range from 20 to 60 wt%, usually from 30 25 to 55 wt% and suitably, in a heavy duty detergent composition, from 25 to 48 wt%.

Depending on the amount and composition of the surfactant system, the zeolite may be the commercially R available zeolite 4A now widely used in laundry detergent 13 C3431 powders. For example, the use of zeolite 4A can give powders having satisfactory flow properties when 17 wt% of surfactant consisting of 30 wt% PAS and 70 wt% nonionic surfactant is present.

However, as the total surfactant loading and/or the proportion of nonionic surfactant is or are increased, the more difficult it is to obtain acceptable powder flow properties. According to a preferred embodiment of the invention, the zeolite builder incorporated in the compositions of the invention is zeolite MAP as described and claimed in EP 384 070A (Unilever Case T3047).

Zeolite MAP is defined as an alkali metal aluminosilicate of the zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, and more preferably within the range of from 0.90 to 1.20.

specially preferred is zeolite MAP having a silicon 20 to aluminium ratio not exceeding 1.07. The calcium binding capacity of zeolite MAP is generally at least 150 mg CaO per g of anhydrous material.

In the present invention, the use of zeolite MAP has another advantage quite independent of its greater building efficacy: it enables more higher total surfactant levels, and more nonionic-rich surfactant systems, to be used without loss of powder flow properties.

Preferred zeolite MAP for use in the present invention is especially finely divided and has a d 50 (as defined below) within the range of from 0.1 to microns, more preferably from 0.4 to 2.0 microns and most preferably from 0.4 to 1.0 microns. The quantity "d 50 14 C3431 indicates that 50 wt% of the particles have a diameter smaller than that figure, and there are corresponding quantities "d 80 "d 9 0 etc. Especially preferred materials have a dg0 below 3 microns as well as a below 1 micron.

Sodium carbonate 10 The compositions in accordance with the invention may contain sodium carbonate, to increase detergency and to ease processing. Sodium carbonate may generally be present in amounts ranging from 1 to 60 wt%, preferably from 2 to 40 wt%, and most suitably from 2 to 13 wt%.

The optional powder structurant Powder flow may be improved by the incorporation of a small amount of a powder structurant, for example, a fatty acid (or fatty acid soap), a sugar, an acrylate or acrylate/maleate polymer, or sodium silicate.

The preferred powder structurant is fatty acid soap, suitably present in an amount of from 1 to 5 wt%. As will be discussed below in the context of processing, this is preferably incorporated as the free acid and neutralised in situ.

Powder flow properties The compositions of the invention are characterised by excellent flow properties, despite the high content of mobile high-performance organic surfactant.

15 C3431 For the purposes of the present invention, powder flow is defined in terms of the dynamic flow rate, in ml/s, measured by means of the following procedure. The apparatus used consists of a cylindrical glass tube having an internal diameter of 35 mm and a length of 600 mm. The tube is securely clamped in a position such that its longitudinal axis is vertical. Its lower end is terminated by means of a smooth cone of polyvinyl chloride having an internal angle of 150 and a lower outlet orifice of diameter 225 mm. A first beam sensor is positioned 150 mm above the outlet, and a second beam sensor is positioned 250 mm above the first sensor.

S"To determine the dynamic flow rate of a powder sample, the outlet orifice is temporarily closed, for example, by covering with a piece of card, and powder is poured through a funnel into the top of the cylinder until the powder level is about 10 cm higher than the upper sensor; a spacer between the funnel and the tube ensures that filling is uniform. The outlet is then opened and the time t (seconds) taken for the powder level to fall from the upper sensor to the lower sensor is measured electronically. The measurement is normally repeated two or three times and an average value taken.

If V is the volume (ml) of the tube between the upper and lower sensors, the dynamic flow rate DFR (ml/s) is given by the following equation: DFR V ml/s t The averaging and calculation are carried out electronically and a direct read-out of the DFR value obtained.

16 C3431 Compositions and components of the present invention generally have dynamic flow rates of at least 90 ml/s, preferably at least 100 ml/s.

Other optional ingredients Fully formulated laundry detergent compositions in accordance with the present invention may additionally 1" 0 contain any suitable ingredients normally encountered, for example, inorganic salts such as sodium silicate or sodium sulphate; organic salts such as sodium citrate; antiredeposition aids such as cellulose derivatives and acrylate or acrylate/maleate polymers; fluorescers; bleaches, bleach precursors and bleach stabilisers; proteolytic and lipolytic enzymes; dyes; coloured speckles; perfumes; foam controllers; fabric softening compounds.

S Preparation of the detergent compositions The compositions of the invention may advantageously be prepared by granulating the zeolite and surfactants in a high-speed mixer/granulator. If the surfactant system includes PAS, that may be incorporated either in salt form (generally as an aqueous paste), or as the free acid (for neutralisation in situ).

An especially preferred process includes the steps of: preparing the surfactant system in the form of a homogeneous mobile liquid blend, and 17 C3431 AU(1) (ii) agglomerating the mobile liquid surfactant blend with the zeolite and other solids present in a high-speed mixer/granulator.

The homogeneous mobile liquid blend may be prepared by mixing PAS paste with the nonionic surfactant.

Alternatively, the nonionic may be admixed during the neutralisation of PAS acid by alkali, for example in a loop reactor, as described and claimed in EP 507 402A (Unilever) filed on 31 March 1992 and published on 7 October 1992.

The high-speed mixer/granulator, also known as a high-speed mixer/densifier, may be a batch machine such as the Fukae (Trade Mark) FS, or a continuous machine such as the L8dige (Trade Mark) Recycler The process is described in more detail, and claimed, in our copending British Patent Application No. 91 25035.7 (Unilever) filed on 26 November 1991, from which the present application claims priority.

The process allows the incorporation of high levels of surfactant without loss of powder flow properties, 25 especially when the zeolite component of the composition is zeolite MAP and/or when soap is present as a V. structurant.

e *eoo *ee 18 C3431 If soap is to be included as a structurant, this is preferably incorporated in the mobile surfactant blend, either as such, or as the corresponding fatty acid (together with a suitable amount of alkali) for neutralisation in situ.

The other optional ingredients mentioned above may be incorporated at any suitable stage in the process. In accordance with normal detergent powder manufacturing practice, bleach ingredients (bleaches, bleach precursors and bleach stabilisers), proteolytic and lipolytic enzymes, coloured speckles, perfumes and foam control granules are most suitably admixed (postdosed) to the dense granular product after it has left the high-speed mixer/granulator.

Of course the compositions of the invention may also be prepared by other processes, involving spray-drying or non-tower technology or combinations of the two.

The invention is further illustrated by the following non-limiting Examples, in which parts and percentages are by weight unless otherwise stated, 19 C3431

EXAMPLES

The abbreviations used in the Examples indicate the following materials: CocoPAS Linear C 12 1 4 primary alcohol sulphate (sodium salt) derived from coconut oil, ex Philippine Refining Co.

E7(s) C13- 5 oxo alcohol 7EO, not "narrow range": Synperonic (Trade Mark) A7 ex

ICI

f* E3(s) C13-1 5 oxo alcohol 3EO, not "narrow range": Synperonic (Trade Mark) A3 ex

ICI

9.* E7 Coconut alcohol 7EO, not "narrow range" *oof:o 9 E3 Coconut alcohol 3EO, not "narrow range" NRE7(s) C 12 1 4 Ziegler linear "narrow range" alcohol 7EO: Alfonic (Trade Mark) 7 ex Vista NRE3(s) C 12 1 4 Ziegler linear "narrow range" alcohol 3EO: Alfonic (Trade Mark) 3 ex Vista NRE7 Coconut alcohol 7EO, "narrow range" 20 C3431 r NRE4.6 NRE4.2 NRE3 Zeolite 4A Zeolite MAP 15 Polymer

LAS

Perborate mono

TAED

Coconut alcohol 5EO, "narrow range" Coconut alcohol 4.6EO, "narrow range" Coconut alcohol 4.2EO, "narrow range" Coconut alcohol 3EO, "narrow range" Wessalith (Trade Mark) P powder ex Degussa Zeolite MAP prepared by a method similar to that described in Examples 1 to 3 of EP 384 070A (Unilever); Si:Al ratio 1.07.

Acrylic/maleic copolymer: Sokalan (Trade Mark) CP5 ex BASF Linear alkylbenzene sulphonate, sodium salt Sodium perborate monohydrate Tetraacetylethylenediamine, as 83 wt% granules Ethylenediaminetetramethylenephosphonic acid, calcium salt: Dequest (Trade Mark) 2041 or 2047 ex Monsanto (34 wt% active) Antifoam granules in accordance with EP 266 863B (Unilever) a r

EDTMP

Antifoam 21 C3431 EXAMPLES 1 TO 10 DETERGENCY Examples 1 to 4 Detergent compositions were following general formulation: prepared to the o o 1

J-

Surfactant system (see below) Zeolite 4A Polymer Carbonate Silicate Metaborate parts 17 32 4 14.5 0.5 16.5 84.50 20.11 37.86 4.73 17.16 0.59 19.53 100.00 S* 20 The surfactant systems were made up as follows Example CocoPAS E7(s) E3(s) NRE7(s) NRE3(s) Both mixtures of 30 parts of 7EO nonionic surfactant and 40 parts of 3EO nonionic surfactant had an average EO number of 4.7 and an HLB value of 10.1.

22 C3431 The percentage of the predominant ethoxylation species (4EO) in the NRE mix was estimated to be 14 wt%.

Detergencies (removal of radio-labelled triolein soil from polyester) were compared in the tergotometer using a 5 g/l product concentration, 240 (French) hard water and a wash temperature of 23 C. The results were as follows: Example triolein removal 1 42.2 2 47.4 3 59.8 4 61.6 Comparison of the results for Comparative Example A, Example 1 and Example 3 shows how increasing the ":":proportion of nonionic surfactant at the expense of PAS increases detergency: while comparison of the results 25 for Examples 1 and 2, and for Examples 3 and 4, shows the detergency benefit obtained by changing to "narrow range" ethoxylated alcohol. The outstandingly good result for Example 4 shows the benefit of combining these two measures.

23 C3431 Examples 5 to 7 A further detergency comparison was carried out, using test cloths carrying a number of different soils.

This experiment was carried out using a Miele (Trade Mark) computer-controlled washing machine, using a product concentration of 5 g/l, and a 30-minute wash at 0 C in 260 (French) hard water.

The compositions had the following general formulation: *parts Surfactant system (see below) 17.0 19.50 Zeolite 4A 30.5 35.00 Sodium carbonate 12.77 14.65 Sodium silicate 0.5 0.57 Sodium perborate monohydrate 16.25 18.65 TAED (83% granules) 7.25 8.32 :'20 EDTMP 0.37 0.42 Antifoam granules 2.50 2.87 87.14 100.00 '25 The surfactant systems were made up as follows Example CocoPAS E7(s) E3(s) NRE7(s) NRE3(s) 5 30 30 40 6 30 30 7 10 40 24 C3431 The results (expressed as reflectance changes at 460 nm) were as follows: Test cloth 1: kaolin and wool fat on polyester/cotton (WFK Reflectance change (delta R 460 Example 5 10.9 Example 6 11.8 Example 7 12.4 S* Test cloth 2: kaolin and wool fat on polyester (WFK Reflectance change (delta R 4 60 20 Example 5 21.4 Example 6 24.5 Example 7 27,5 Test cloth 3: kaolin and sebum on cotton (WFK Reflectance change (delta R 460 Example 5 16.5 Example 6 17.4 Example 7 18.8 25 C3431 Test cloth 4: kaolin and sebum on polyester (WFK Reflectance change (delta R 4 Example 5 18.7 Example 6 21.5 Example 7 25.1 Example 8 15 Using the same tergotometer procedure as in Examples S. 1 to 4, the detergencies of various surfactant mixtures containing different ethoxylated coconut alcohols were compared.

20 In each case the compositions were as given in Example 1, and the surfactant systems consisted of 30 wt% •cocoPAS, and 70 wt% ethoxylated alcohol. The ethoxylated alcohol component was made up 25 by mixing E7 and E3 (broad range) in varying proportions, or (ii) by mixing NRE7 and NRE3 (narrow range) in varying proportions, or (iii) by use of a single narrow range ethoxylate.

The true degrees of ethoxylation will be recognised from the Table given earlier in this specification.

26 C3431 Detergencies removal of radio-labelled triolein from polyester) as a function of degree of ethoxylation and starting ethoxylated alcohol are shown in the following Table.

(ii) (iii)

EO

(average) E7 E3 NRE7 NRE3 Single NRE 15 20 25 S. 1 *o* 0 oo 6.88 5.96 5.90 5.22 5.20 5.17 4.94 4.86 4.70 4.66 4.49 4.27 3.96 3.75 3.01 3.00 9.9 (E7) 14.1 (NRE7) 15.7 18.4 25.1 21.0 21.2 23.3 30.7 (NRE4.6) 26.4 31.1 35.7 (NRE4.2) 27.3 35.5 36.4 (NRE3) 28.5 (E3) These results illustrate the advantage of average degrees of ethoxylation of 6 or below; the improvements obtained by moving to narrow range ethoxylates; and the especial benefits of using a single, narrow range material, in particular NRE4.2.

27 C3431 Example 9 The procedure of Example 8 was repeated using a series of compositions having a more nonionic-rich surfactant system: 10 wt% cocoPAS and 90 wt% ethoxylated alcohol. The results are shown in the following Table.

(ii) (iii) 15 .:20 2 5

EQ

(average) 6.88 5.96 5.20 5.17 4.94 4.70 4.66 4.49 4.31 4.27 3.75 3.01 3 .00 E7 E3 NRE7 NRE3 Singrle NRE 22. 6 (E7) 34.3 (NRE7) 44.1 35.3 35.5 36.1 45.5 51.5 (NRE4.6) 44 43.*0 43.*1 53.5 (NRE4.2) 44.1 35.4 (NRE3) 37.2 (E3) Again the benefits of using narrow range ethoxylates, especially single materials, are apparent.

dn C/ kr-O C3431 lo be 31 EXAMPLES 1 POWDER PROPERTIES POWDER

PROPERTIES

Examples 11 and 12, Comparative Example A 1 09 *0 3 .0 Detergent base powders of high bulk density, consisting of the surfactant system, zeolite and (in some cases) sodium carbonate, were prepared by agglomeration in a Fukae FS100 batch high-speed mixer/granulator.

These powders are not intended as fully formulated detergent compositions, but are readily converted to such compositions by admixture (postdosing) of other components such as bleach ingredients, enzymes, lather control granules and perfume.

The surfactant system was as follows: wt% cocoPAS wt% E7(s) wt% E3(s) The compositions, in parts by weight and percentages, are shown below.

I

A 1D 1:' Surfactant Zeolite 4A Zeolite MAP Carbonate 17 (38.64) 27 (61.36) 17 (31.48) 27 (50.00) 17 (40.48) 25 (59.52) 10 (18.52) 44 (100.00) 54 (100.00) 42 (100.00) Q- C3431 A homogeneous liquid blend of the surfactants was prepared by neutralising PAS acid with sodium hydroxide solution in a loop reactor in the presence of the nonionic surfactants. Zeolite and (where present) sodium carbonate were dosed into the Fukae mixer, the liquid surfactant blend added and the mixture granulated.

The granular product was then dried using a fluidised bed.

In the case of Comparative Example A it proved impossible to obtain a granular product; the mixture formed a solid mass. The addition of 10 parts of sodium carbonate (Example 11) enabled a granular product to be Sprepared. With zeolite MAP (Example 12), at a slightly 15 lower level, the same amount (in parts actually a slightly higher percentage loading) of the surfactant eystem could be incorporated without the need for sodium carbonate, and a free-flowing granular product was obtained.

*eoo oooo* *o o C3431 Comparative Examples B to E Further attempts to prepare base powders containing zeolite 4A with differing amounts of surfactant (the same system as in Examples A, 11, and 12) and carbonate were unsuccessful: Compositions in narts by weiaht 15 oo o Surfactant Zeolite 4A Carbonate

C

15.3 27

D

17.2 27

E

18.5 27 0.

47.3 54.2 60.5 Compositions in percentaaes Surfactant Zeolite 4A Carbonate 32.50 67.50

C

32.35 57.08 10.57 31.73 49.82 18.45 30.58 44.63 24.79 Composition B produced a solid mass, while Compositions C, D and E initially produced free-flowing powders which, however, lost their flow on drying.

91 '.A4 d^A> af 31 2 ExamplII ~c 14 C3431 An experiment similar to that of Comparative Examples B to E, but using zeolite MAP, gave powders having good flow properties, even at substantially higher surfactant contents. The compositions and powder properties are shown below.

Compositions in parts by weight *1 20 oe Surfactant Zeolite MAP Carbonate 18.4 25 4.4 47.8 19.6 25 20.8 13.9 59.7 8.9 53.5 Compositions in percentages 25 Surfactant Zeolite MAP Carbonate 40.48 59.52 38.49 52.30 9.21 36.64 46.73 16.64 34.84 41.88 23.28 Powder properties Bulk density 794 817 829 867 DFR (ml/s) 100 93 56 72 C3431 is I Examples we..

C. 9 o* 15 20

C

'25 Compositions similar to those of Comparative Examples B to E were prepared, but this time fatty acid soap was present.

The method of preparation of these powders was slightly different from that used in previous Examples.

A homogeneous mobile blend was prepared by mixing PAS in sodium salt form (70 fatty acid, sufficient sodium hydroxide solution to neutralise the fatty acid, and the nonionic surfactants. Ingredients were dosed into the Fukae mixer in the order zeolite, carbonate, surfactant blend, granulation/densification was carried out as in previous Examples, and the products were finally dried using a fluidised bed.

Powders having excellent flow properties were obtained.

Compositions /4 parts narts Surfactant Zeolite 4A Carbonate 17 25.95 32 48.85 14.5 22.14 29.18 54.94 12.45 3.43 7 25 2 Soap 3.05 65.5 100.00 58.25 100.00 33 34 C3431 Powder properties Bulk density (g/l) DFR (ml/s) 918 122 872 143 These Examples, when compared to Comparative Examples C to F, show that the inclusion of fatty acid soap made it possible to produce good high density powders from formulations unprocessable in its absence.

J7 cnkd J Examples A MV 1 Compositions similar to those of Examples 16 and 17 were prepared, by the same method, but using zeolite MAP instead of zeolite 4A.

Compositions 2 25 parts parts Surfactant Zeolite MAP Carbonate 17 25.95 32 48.85 14.5 22.14 2 3.05 65.5 100.00 29.18 54.94 12.45 Soap 7.25 2 58.25 3.43 100.00 C3431.

Powder properties Bulk density 980 959 DFR (ml/s) 131 143 II I~ 14 Comparison of these Examples with ExmlsA 2t=shows that the inclusion of soap improved flow, but when, zeolite MAP was used it was not essential in order to obtain acceptable powders.

3 C3431 Examples 2 and 24, Comparative Examples F and G Detergent base powders generally as described in

II

Examples 4 =)1Sr and A were prepared using a different surfactant system: wt% cocoPAS wt% E7(s) wt% E3(s) The surfactant system was prepared as a homogeneous mobile blend by the method described in Examples q3d=; and A, and the other process steps were also carried out S: as in those Examples.

Compositions in parts by weight F 20 G 21 Surfactant 17 17 17 17 SZeolite 4A 27 27 Zeolite MAP 25 Carbonate 25 44 69 42 57 C3431 Compositions in percentages Surfactant Zeolite 4A Zeolite MAP Carbonate 38.64 61.36 24.64 39.13 40.48 29.82 59.52 43.86 26.32 36.23 1 In the case of Comparative Examples F and G it proved impossible to obtain a granular product; both mixture formed a solid mass. The addition of 25 parts of sodium carbonate to the zeolite 4A-based composition (Example 20) was required to enable a granular product to be prepared. With zeolite MAP (Example 21), only parts of sodium carbonate were required.

ooe o 37 as C3431 Examples 3. and 2, Comparative Example H 17 crnc\ \l Compositions similar to those of Examples 4 lz=a were prepared, but containing higher levels of zeolite.

Compositions in parts by weight .1 2 Surfactant 17 Zeolite 4A 32 Zeolite MAP Carbonate 49 Compositions in percentages Surfactant Zeolite 4A Zeolite MAP Carbonate

H

34.69 65.31 22 28.81 54.24 23 34.69 65.31 16.95 Composition H would not give a granular product: parts of sodium carbonate were required to produce a processable formulation. With zeolite MAP at this level, however, no carbonate was required despite the high percentage level of surfactant in this composition (Example 23).

3 C3431 A3 Example t, Comparative Examples J and K Formulations based on zeolite 4A, with and without soap, were prepared using the surfactant system of Examples 20 to 22. The fatty acid soap was incorporated by mixing fatty acid and an equivalent amount of sodium hydroxide solution into the surfactant blend (prepared as described in Example 11) before addition of the blend to the Fukae mixer.

20 5 Compositions in parts by weight Surfactant Zeolite 4A Carbonate 14.5 17 32 14.5 2 65.5 17 32 14.5 4 67.5 Soap 63.5 Compositions in Dercentaces Surfactant Zeolite 4A Carbonate 26.77 50.39 22.83 25.95 48.85 22.14 25.19 47.41 21.48 Soap 3.05 5.93 C3431 Composition J gave a non-flowing product both before and after drying, while Composition K initially gave a good product but lost its flow on drying. A larger amount of soap (Example4A) gave an excellent powder having a bulk density of 920 g/l and a dynamic flow rate of 109 ml/s.

Ah cand 9 Examples Compositions similar to those of Examples 24 and J but containing zeolite MAP and a higher level of surfactant were prepared.

Compositions 26 parts parts Surfactant 20,5 30.60 20.5 29.71 1 o 2 20 Zeolite MAP Carbonate 32 47.76 14.5 21.64 32 14.5 2 69.0 46.37 21.01 2.90 Soap 67.0 i i-\ C3431 AU(l) Powder properties Bulk density (g/1) 928 115 898 114 DFR (ml/s) ~i S

S.

S S

S.

S S a a.

S

a a

S

*555

S.

J4 C3431 AU(1) Example 26 A composition similar to that of Example 23 but containing a different nonionic surfactant, NRE5, was prepared. All solid components had a particle size lower than 200 microns.

The method of preparation was substantially as described in Example 10. The mean residence time of the granular detergent composition in the batch high-speed mixer/granulator was approximately 3 minutes.

Comosition Surfactant: PAS 8.3 19.5 43.7 Zeolite 4A Carbonate Water 16.2 12.1 100.0 The granular detergent composition obtained had a bulk density of about 770 g/l and a dynamic flow rate of 101 ml/s.

4- C3431 .7 ctnA aia Examples a-±r-=a2 Granular detergent compositions similar to that of Example.3 were prepared using a continuous high-speed mixer/granulator, the Ldige (Trade Mark) Recycler The liquid surfactant mix included fatty acid in combination with a stoichiometric amount of sodium hydroxide, which during the course of the mixing and densifying process formed soap.

The rotational speed was 1600 rpm and the mean residence time of the granular mixture in the Recycler was approximately 10 seconds.

The compositions of the granular materials leaving the Recycler were as follows.

31 32 Surfactant: PAS 8.5 8.3 19.4 18.8 Zeolite 4A 52.6 47.1 25 Carbonate Soap 2.9 2.9 Water 16.4 14.9 100.0 100.0 Bulk densities were about 700 g/l, particle sizes 500-600 microns, and powder properties were good.

C3431 Examples 33 to 35, Comparative Example M Fully formulated detergent powders were prepared to the formulations given below.

A

Base powders LAS 7.85 Coco PAS 5.20 5.20 1.70 E7(s) 3.92 5.20 E3(s) 5.23 6.60 NRE7(s) 5.20 6.80 NRE3(s) 6.60 8.50 Soap 2.00 2.00 2.00 2.00 Zeolite 4A 32.00 32.00 32.00 ~Zeolite MAP 32.00 99.*Carbonate 11.52 11.52 11.52 Fluorescers 0.81 0.81 0.81 0.81 SCNC 0.60 0.60 0.60 0.60 moisture 9.00 9.00 9.00 9.00 Postdosed 99*: Carbonate 11.52 Silicate 0.45 0.45 0.45 0.45 Perborate mono 15.00 15.00 15.00 15.00 TAED 7.75 7.75 7.75 7.75 EDTMP 0.37 0.37 0.37 0.37 Enzymes 1.00 1.00 1.00 1.00 Antifoam 2.50 2.50 2.50 2.50 Perfume 0.60 0.60 0.60 0.60 100.00 10.0 100.00 100.00 100.00 4k 4S C3431 Comparative Composition M is a high-performance concentrated powder based on a different surfactant system (LAS with nonionic surfactants) similar to that used in premium powders p:esently on sale in Europe.

Surfactant systems (wt%) LAS 46 Coco PAS 30 30 E7(s) 23 30 E3(s) 31 40 S. NRE7(s) 30 15 NRE3(s) 40 100 100 100 100 The total amount of (non-soap) surfactant in each 20 formulation was 17 wt%.

All base powders were prepared in the Fukae FS100 batch high-speed mixer/granulator mentioned previously.

25 Composition M was prepared as follows. Zeolite and .i carbonate (including an additional amount for neutralisation of LAS acid) were dosed into the Fukae mixer, followed by LAS acid, then a homogeneous surfactant blend (nonionic surfactant), fatty acid and an equivalent amount of sodium hydroxide solution). After granulation, the powder was dried using a fluidised bed, and the remaining ingredients postdosed.

4f C3431 Compositions 33 and 34 were prepared as follows.

Homogeneous surfactant blends were prepared by mixing PAS paste nonionic surfactant, fatty acid and an equivalent amount of sodium hydroxide solution. Zeolite and carbonate were dosed into the Fukae, followed by the surfactant blend. After granulation, the povders were dried using a fluidised bed, and the remaining ingredients postdosed.

Composition 35 was prepared similarly except that no carbonate was present during granulation.

Powder properties .15 .15 L 30 31 Bulk density 861 826 841 841 DFR 89 111 120 128 Detergency results Detergency was assessed in a Miele washing machine, in the presence of a soiled load, using a product concentration of 5 g/l, 260 (French) hard water, and a wash temperature of 30 C. The measure of detergency was the change in reflectance (460 nm) of a polyester test cloth soiled with kaolin and sebum (WFK Delta R46 16.2 15.0 15.7 17.2 C3431 AU(1) Examples 32 and 33 Further detergent powder formulations, containing zeolite MAP and coconut nonionic surfactants, are shown below.

Base powders Coco PAS E7 E3 Soap Zeolite MAP Fluorescers

SCMC

Moisture Postdosed Carbonate Silicate Perborate mono

TAED

EDTMP

Enzymes Antifoam Perfume 5.20 5.20 6.60 2.00 32.00 0.81 0.60 9.00 1.70 6.80 8.50 2.00 32.00 0.81 0.60 9.00

C

*n 11.52 0.45 15.00 7.75 0.37 1.00 2.50 0.60 11.52 0.45 15.00 7.75 0.37 1.00 2.50 0.60 100.00 100.00 Similar compositions may be formulated containing the narrow-range coconut nonionic surfactants NRE7 and NRE3, instead of the broad range materials E7 and E3, in the same proportions; or instead using one of the single materials NRE5, NRE4.6 or NRE4.2. j(7.