GB2234982A

GB2234982A - Detergent laundry bars

Info

Publication number: GB2234982A
Application number: GB8918278A
Authority: GB
Inventors: Peter James Powers
Original assignee: Unilever PLC
Current assignee: Unilever PLC
Priority date: 1989-08-10
Filing date: 1989-08-10
Publication date: 1991-02-20
Also published as: BR9003931A; MY107061A; IN171325B; ZA906338B; GB8918278D0

Abstract

A method of making detergent laundry bars containing anionic detergent active, detergency builder and other ingredients in which method at least one component of a two-component hardening system is mixed with the detergent active prior to neutralisation, the two components being a polyvalent metal compound and a silaceous compound.

Description

DETERGENT COMPOSITION This invention relates to non-soap detergent laundry bars, used in certain countries for fabric washing and for cleaning surfaces. Such bars contain detergent active and detergent builder materials together with fillers and usually other components.

Such bars require an acceptable physical strength so that they retain their structural integrity during handling transport and use. The hardness of the bars, at the time of manufacture and subsequently, is an especially important property.

Techniques are known for enhancing the hardness of bars, generally consisting of including certain ingredients to promote hardness, or adding particular ingredients at a prescribed stage in manufacture.

We have now devised an alternative route for structuring and hardening bars by addition of ingredients during manufacture. This is advantageous in that it extends the range of possibilities available when deciding on a bar formulation. It is also advantageous in that - in certain forms of the invention - it is possible to achieve high levels of detergent active, and/or low pH, and/or high water content - the last of these can enable use of detergent actives with higher levels of water associated with them such as slurries and pastes.

In a first aspect this invention provides a method of making detergent laundry bars containing anionic detergent active, detergency builder and other ingredients, in which method a plurality of components including the detergent active and builder are mixed together and the mixture is formed into bars, characterised by mixing at least one component of a two-component hardening system with the acid form of at least some detergent active prior to neutralisation thereof and incorporating the other component of the said system before or after the neutralisation, the said two components being a polyvalent metal compound and a silaceous material, with the proviso that if silaceous material is mixed in before the neutralisation and the polyvalent metal compound is added after neutralisation, then the metal thereof is aluminium.

Thus the possibilities are: add polyvalent metal compound before neutralisation followed by silaceous material before or after the neutralisation; add silaceous material before neutralisation followed by polyvalent metal compound, also before the neutralisation; add silaceous material before neutralisation followed by an aluminium compound after the neutralisation.

In a second aspect this invention provides a detergent laundry bar produced by the above method. Suitable polyvalent metal compounds are salts having a polyvalent metal as cation or within the anion thereof.

We have found that with this method of making bars, it is possible to use a number of different forms of silaceous material including alkali metal silicate. Subject to the proviso above, it is possible to use a number of different polyvalent metal compounds including salts with aluminium as cation and salts which do not have aluminium as cation.

Although this invention achieves bar hardening by use of two components, that is to say the polyvalent metal compound and the silaceous material, it is preferred to incorporate a water soluble metal phosphate into the mixture before the polyvalent metal compound and the silaceous material come together. Preferably this water soluble phosphate is mixed with the acid form of the detergent active prior to neutralisation. Such incorporation of phosphate can provide an acceleration and enhancement of the bar hardening. It is then preferred that any such water soluble phosphate is added prior to the polyvalent metal compound.

In the less preferred forms of the invention where polyvalent metal compound and silaceous material come together in the absence of phosphate, some water soluble phosphate may nevertheless be added subsequently and will make some contribution to bar hardening.

Silaceous material can be added before or after neutralisation, but it is desirable to avoid neutralisation of alkaline silicate with the acid form of detergent active.

The essential and optional components for use in a bar made in accordance with this invention will now be discussed in turn.

Detergent active and builder components are well characterised in detergent bar technology. These components are described in "Surface Active Agents" by Schwartz and Perry (Interscience 1958).

Specific examples of anionic detergent actives useful in this invention are: linear and branched alkyl benzene sulphonates, alkane sulphonates, secondary alcohol sulphates, primary alcohol sulphates, alpha olefin sulphonates, alkyl ether sulphates, fatty acyl ester sulphonates, and mixtures of these. The invention is particularly applicable when at least part of the detergent active is alkyl benzene sulphonate, or a mixture thereof with fatty acyl ester sulphonate or primary alcohol sulphate.

Generally the amount of detergent active (reckoned as anhydrous) will be from 5 to 65 wt % of the total bar composition, preferably 10 to 45 or 55 wt %, based on the total composition. Preferably the amount of detergent active present before the hardening materials are added is such as to provide at least 5 wt % of the final bar composition.

Some detergent active from a category other than anionic, such as nonionic, amphoteric or zwitterionic may be included within these quantities. Preferably then the preparation of anionic detergent active is such as to provide at least 5 wt %, better at least 10 wt % of the total bar composition.

One group of detergency builders are water soluble phosphates, e.g. sodium tripolyphosphate, pyrophosphate, orthophosphate, and metaphosphates (also called glassy phosphates). Phosphates intended to act as builder, rather than to function in bar hardening in accordance with this invention can be added after both neutralisation and the addition of hardening materials.

Part of any phosphate added as hardening material prior to the silaceous material and/or polyvalent metal compound may also function as a detergency builder. Indeed the amount may be chosen so as to provide a surplus to function as builder.

Examples of other builders are water soluble carbonates, e.g. sodium carbonate used in excess of the quantity required for neutralisation; organic builders, e.g. sodium nitrilotriacetate, sodium tartrate, sodium citrate, trisodium carboxymethyl oxysuccinate, sodium oxydisuccinate, sodium sulphonated long-chain monocarboxylic acids, polymeric carboxylate builders such as polyacrylic acid, maleic acid copolymers and oxidised starch and cellulose; and aluminosilicate ion exchangers; e.g.

zeolite 4A.

The water soluble phosphate which is preferably added as hardening material may be orthophosphate, pyrophosphate, tripolyphosphate, glassy phosphate or other phosphate condensates. A description of the various phosphate condensates is given in "Phosphorus and its compounds" by J.van Waser. Any water soluble salt can be used, but sodium salts will generally be used, as the most readily available and cost effective. A mixture of phosphates may be used.

A preferred amount of this phosphate used as hardening material is from 1 to 20t reckoned as anhydrous phosphate by weight of the final bar composition, more preferably 3 to 12%.

Generally the total amount of detergency builder plus any phosphate functioning as a hardening material (both reckoned as anhydrous) lies in the range from 5 to 60 wt % preferably 8 to 45 wt 8 of the total bar composition. When phosphate is added before the silaceous material and/or polyvalent metal compound, the amount so added is preferably at least 1 wt % of the total bar composition.

The polyvalent metal compounds may contain various metals. Specific possibilities are aluminium which may for instance be introduced as aluminium sulphate, other salts with aluminium as cation or as sodium aluminate, magnesium which may be used as its sulphate or other salt with magnesium as cation and boron which may be introduced as boric acid or as a neutralised salt. Other group Ila, group lib, transition or lanthanide metal salts can be used but are not preferred.

A preferred amount of this polyvalent metal compound is from 0.5 to 12% reckoned as anhydrous material by weight of the final bar composition, more preferably from 2 to 10%.

The silaceous material may be any of: silica itself in finely divided form, e.g. micronised silica gels, precipitated silicas and silica aerosols; silicates, which may be water-soluble metal, alkaline or neutral silicates; polymeric silicates and amorphous synthetic sodium aluminosilicates such as Alusil N (ex J Crosfield); serpentine-kaolin, talc-pyrophyllite and smectite clays. Examples of such clays are kaolin, talc trioctahedral smectites such as saponite, and dioctahedral smectites such as montmorillonite. Smectite clays may be associated with sodium, calcium or other exchangeable cations.

The preferred amount of silaceous material is such as to introduce from 1 to 10% of silica into the bar composition and more preferably 2 to 8%, reckoned as anhydrous silica by weight of the final bar formulation.

The weight ratio of the polyvalent metal compound (reckoned as anhydrous) and the silaceous material (reckoned as anhydrous silica) preferably lies within the range 5 : 2 to 2 : 4.

If the silaceous material is a water soluble simple silicate it is preferred that it is added to a mixture which is not acidic, i.e. after any neutralisation of detergent active. Addition before neutralisation is possible, but the precipitation of silica in the acid environment may lead to formation of some particles of silica large enough to give an undesirable gritty feel to the bars.

If a clay such as a smectite is used, this can be added before neutralisation because hydrolysis and precipitation will not be a problem. Likewise, a finely divided silica can be added before neutralisation.

Built NSD bars often contain a proportion of filler which although generally chemically inert is significant in contributing to the properties of the bar. An appropriate range for such filler (if used) is 5 to 60t by weight of the composition. The filler may consist of water soluble salts such as sodium sulphate but possibly it includes waterinsoluble filler. The filler present may even all be water insoluble and accordingly the possible amount of water insoluble filler is 5 to 60 wt %. Examples of water insoluble fillers are calcite, aluminosilicate, dolomite, feldspar, calcium silicate and calcium sulphate, (and also clays such as talc, kaolin and bentonite if these are not complexed in accordance with this invention).

Other ingredients may also be present in the composition. These include sodium carboxymethyl cellulose and cellulose ethers, cellulose itself, starch, lather enhancing agents such as long chain alkanolamides and alcohols exemplified by coconut monoethanolamide, coconut diethanolamide and coconut alcohol, humectants such as glycerol, sorbitol and mono- and disaccharides, colouring materials, enzymes, fluorescers, opacifiers, germicides, desiccants such as calcium, magnesium and aluminium oxides, perfumes and bleaching agents. Alkanolamines may be included, as described in our UK published patent application 2184452A.

A built detergent bar in accordance with this invention will generally be substantially rigid, enabling it to be rubbed against an item of laundry. Of course if a bar is soaked in water or stored under conditions of excessive humidity it may lose its strength and become plastically deformable by hand pressure.

To prepare bars according to this invention, it is preferred to begin with the acid form of the detergent active, admix phosphate (if any is added before neutralisation) then one hardening component and next the other and neutralise or alternatively neutralise and thereafter add the other hardening component, then in succession mix in any other ingredients such as filler(s), any remaining phosphate and finally minor ingredients such as perfume. Mixing can be carried out in a high shear mixer and be followed by conventional extrusion and bar stamping.

Neutralisation is preferably effected by the known procedure of dry neutralisation, in which a carbonate (usually soda ash) is added to the acidic mixture.

Neutralisation in other ways, such as with very concentrated sodium hydroxide solution or a mixture of sodium hydroxide and soda ash, is also possible.

The invention will be further explained and illustrated by means of the following examples, in which all proportions and percentages are by weight unless otherwise stated.

In these examples, bars with the compositions given were manufactured on a conventional plant for the manufacture of NSD bars. This plant consisted of a sigma mixer, mill and vacuum plodder. The bars were tested for bar hardness immediately after extrusion (while the bar was still hot) after one hour and after 24 hours and intervals up to 1 week. The test was carried out by means of a penetrometer.

The penetrometer used was a SUR type PNR 10 (Sommer und Runge of Berlin DBR). The needle had a point angle of 9" 10' and was forced into a plane bar surface under a total load of 100g for 10 seconds.

Example 1 Bars were manufactured by the following procedure, in which mixing and neutralisation stages were all carried out in the above mentioned sigma mixer.

Sodium tripolyphosphate (450g) was mixed with linear C12 alkyl benzene sulphonic acid (Petrelab 550, average M.W.

321, 3.6Kg.). After mixing for 2 minutes aluminium sulphate hydrate il.lKg) was then added and mixing continued for a further 2 minutes. Silica gel (Gasil 23 ex Crosfield, 450g) was then added. After a further 5 minutes mixing neutralisation of the sulphonic acid was effected by adding excess sodium carbonate (2.92Kg) and some water (900g). On completion of neutralisation the other bar ingredients, namely more sodium tripolyphosphate (450g), sodium pyrophosphate (450g), calcite (5.03Kg), and the minor ingredients, fluorescer (36g), titanium dioxide (23g), pigment (50%, 6g) and perfume (38g) were added in succession while mixing continued. The ultimate dough was then milled and plodded to produce NSD bars.

These bars could readily be handled as they were produced.

The final composition of the bars in parts per 100, was: LAS (Petrelab 550) 25 Aluminium sulphate hydrate 7.4 Silica gel 3.0 Sodium carbonate 10.0 Sodium tripolyphosphate 6.0 Sodium pyrophosphate 3.0 Calcite 33.7 Minors 0.67 Total water 10.0 Penetrometer results were: Time Penetrometer reading (mm) 0 4.1 at 59"C 1 hour 1.5 24 hours 1.4 1 week 1.2 Example 2 and Comparative Examples 2A and 2B Using the procedure of Example 1, with all sodium tripolyphosphate added before neutralisation, one bar composition embodying the invention and two comparative compositions were prepared. The comparative compositions omitted aluminium sulphate and silica respectively.

The compositions in parts per 100 and the penetrometer results obtained with them are set out in the following Table 1. The bar with phosphate, plus aluminium salt plus silica had greater hardness (lower penetration) than either of the other two.

TABLE 1 Example No: 2 2A 2C Ingredient: LAS (Petrelab 550) 25.0 25.0 25.0 Sodium tripolyphosphate 9.0 9.0 9.0 Aluminium sulphate hydrate 7.4 7.4 Silica 3.0 - 3.0 Sodium carbonate 10.0 10.0 10.0 Added water 7.3 6.5 9.1 Calcite 33.2 36.9 41.6 Minors 0.67 0.67 0.67 Total water 11.3 10.6 10.1 Hardness Data Penetrometer Reading (mm) Time 0 3.1(54 C) 7.6(47"C) 12.3(59"C) 24 hours (RT) 1.4 4.2 4.2 1 week (RT) 1.31 2.9 3.5 Example 3 Bars were manufactured by the following procedure, utilising a sodium alkaline silicate solution as the silaceous material. All mixing stages including neutralisation were carried out in the sigma mixer.

Sodium tripolyphosphate (750g) was mixed with linear alkyl benzene sulphonic acid (Petrelab 550, average MW 321, 3.6Kg). After mixing for 2 minutes aluminium sulphate hydrate (1.1Kg) was added and mixing continued for a further 2 minutes. Neutralisation of the sulphonic acid was effected by adding an excess of light anhydrous soda ash (2.9Kg) and some water (500g). When the neutralisation was complete alkaline silicate solution (48%, 906g) was added and the dough mixed for a further 2 minutes at 60-650C. The other bar ingredients, namely more sodium tripolyphosphate (600g), calcite (5.1Kg), pigment (50%, 6g), fluorescer (36g), titanium dioxide (23g) and perfume (38g) were then added in sequence while mixing. The ultimate dough was milled and plodded to produce NSD bars.

These bars could readily be handled as they were produced.

The final composition of the bars in parts per 100, was: LAS (Petrelab 550) 25 Aluminium sulphate hydrate 7.4 Sodium alkaline silicate (48% solution) 6.1 Sodium carbonate 10.0 Sodium tripolyphosphate 9.0 Calcite 33.8 Minors 0.67 Added water 3.3 Impurities balance to 100% Total bar water content 10.7 Example 4 The procedure of Example 3 was repeated using pyrophosphate: the tripolyphosphate added before neutralisation was replaced with the same weight of sodium pyrophosphate as was the tripolyphosphate added after neutralisation.

Example 5 Bars were manufactured by the following procedure, using some preneutralised detergent active and neutralising the remainder of the detergent active during the procedure.

Sodium coconut alcohol sulphate powder (94%, 3575g) and water (1000g) were mixed together to produce a homogenous paste at 50-60"C in Sigma mixer. Alkylbenzene sulphonic acid of molecular weight 324 (97%, 2200g) and sodium tripolyphosphate (1000g) were then added and mixed together for 2 minutes. Aluminium sulphate hydrate (Al2 (SO4 )3 14.5HzO, 1480g) and silica gel (Gasil 23 ex Crosfield 600g) were then added sequentially and mixed in for a further 5 minutes. Sodium carbonate was then added in an amount (3.4Kg) which was in excess of that needed to neutralise all the acidic species. On completion of the neutralisation coconut alcohol (400g) was added followed by calcite (4.72Kg).After mixing for 2 minutes, sodium pyrophosphate (800g), sodium tripolyphosphate (1200g), fluorescer (48g) and titanium dioxide (30g) were added. Finally, after mixing for 2 minutes blue pigment (50%, 8g) water (60g) and perfume (80g) were added and mixed in to produce a dough with a homogeneous colour. The resultant dough was then milled and plodded to produce NSD bars.

Examples 6 to 39 A number of bar compositions were manufactured, following the procedure of Example 3 when a water soluble silicate was employed ana- following the procedure of Example 1 when silica itself or a clay was used. Alkyl benzene sulphonate and fatty acid ester sulphonate were added as acids and neutralised in situ. Other detergent actives were used in preneutralised form and were added to the acid form of alkyl benzene sulphonate or fatty acyl ester sulphonate as in Example 5.

The compositions and the penetrometer results for these bars are set out in the following tables which include the values for Examples 1,3,4 and 5. The amount of phosphate added before neutralisation is shown separately from the amount, if any, added after neutralisation. The bar constituents are listed in order of addition. Some comparative examples are included in these tables.

Example No: 3 6 7 3A* 4 8 9 LINEAR ALKYL (C12) BENZENE SULPHONATE 25 25 25 25 25 25 25 SODIUM ORTHOPHOSPHATE nil nil nil nil nil 4 nil SODIUM TRIPOLYPHOSPHATE 5 5 5 5 nil nil 3 SODIUM PYROPHOSPHATE nil nil nil nil 5 nil nil ALUMINIUM SULPHATE HYDRATE 7.4 nil nil 7.4 7.4 7.4 nil SODIUM ALUMINATE nil nil nil nil nil nil 6.0 MAGNESIUM SULPHATE HYDRATE nil 7.4 nil nil nil nil nil BORIC ACID nil nil 4.1 nil nil nil nil SODIUM CARBONATE 10 15 15 10 10 10 15 ADDED WATER 3.3 3.7 6.5 6.5 3.3 3.3 6.9 ALKALINE SILICATE (48% SOLUTION) 6.1 6.1 6.1 nil 6.1 6.1 nil SODIUM TRIPOLYPHOSPHATE 4 4 4 4 nil 5 6 SODIUM PYROPHOSPHATE nil nil nil nil 4 nil nil CALCITE 3 33.8 33.1 33.2 36.9 33.8 34.0 18.2 KAOLIN nil nil nil nil nil nil 13.9

MINORS AND RESIDUALS < BALANCE < ---------------BALANCE-------------- > TOTAL BAR WATER 10.7 9.7 10.4 10.6 10.7 10.7 7.8 PENETROMETER READING (mm) INITIAL (55-60"C) 3.2 4.7 3.8 7.4 4.0 8.0 4.3 24 HOUR (RT) 2.2 2.3 1.3 3.2 2.2 2.2 2.8 1 WEEK (RT) 1.9 1.6 1.0 2.9 1.8 1.5 1.6 * COMPARATIVE: no silaceous material.

Example No: 10 11 llA* 12 13 COCONUT FATTY ACYL ESTER SULPHONATE 16.8 16.8 16.8 16.8 16.8 SODIUM TRIPOLYPHOSPHATE 5.0 6.0 6.0 6.0 6.0 ALUMINIUM SULPHATE HYDRATE nil 14.8 nil 14.8 14.8 MAGNESIUM SULPHATE HYDRATE 7.4 nil nil nil nil KAOLIN nil nil nil nil 5.9 BENTONITE nil nil nil 5.9 nil SILICA nil 5.9 nil nil nil BRANCHED ALKYL (C12) BENZENE SULPHONATE 11.2 11.2 11.2 11.2 11.2 SODIUM CARBONATE 20 15 15 15 15 ADDED WATER nil 1.7 8.1 1.7 1.7 ALKALINE SILICATE (48% SOLUTION) 6.1 nil nil nil nil SODIUM SULPHATE 24.7 13.8 35.6 13.7 13.9 SODIUM PYROPHOSPHATE 3.0 3.0 3.0 3.0 3.0

MINORS AND RESIDUALS BALANCE < ------------BALANCE------------ > TOTAL BAR WATER 7.4 10.7 10.4 10.5. 10.5 PENETROMETER READING (mm) INITIAL (55-60 C) 8.2 3.0 13.0 3.6 3.3 24 HOUR (RT) 4.0 1.7 5.7 1.2 2.0 1 WEEK (RT) 1.8 0.6 5.0 0.7 1.0 * COMPARATIVE: no polyvalent metal compound.

Example No: 5 14 15 16 17 18 60/40 28t 20/80 40/60 60/40 60/40 PAS/ PAS FAES/ FAES/ FAES/ FAES/ ABS ABS ABS ABS PAS COCONUT PRIMARY ALCOHOL SULPHATE 16.8 28.0 nil nil nil 11.2 ADDED WATER 5.0 9.3 nil nil nil 3.0 COCONUT FATTY ACID ESTER SULPHONATE nil nil 5.6 11.2 16.8 16.8 BRANCHED ALKYL (C12) BENZENE SULPHONATE 11.4 nil 22.4 nil nil nil UREA nil 1.0 nil nil nil nil MONOETHANOLAMINE nil 1.0 nil nil nil nil SODIUM ORTHOPHOSPHATE nil nil nil nil nil nil SODIUM PYROPHOSPHATE nil nil nil nil nil nil SODIUM TRIPOLYPHOSPHATE 5 15 5 5 6 5 ALUMINIUM SULPHATE HYDRATE 7.4 7.4 2.8 11.1 14.8 7.4 SILICA 3.0 nil 1.5 4.5 5.9 3.0 BRANCHED ALKYL (C12) BENZENE SULPHONATE nil nil nil 16.8 11.2 nil SODIUM CARBONATE 10 10 15 15 15 15 WATER ADDED nil nil nil nil 1.7 nil COCONUT ALCOHOL 2.0 nil nil 1.0 2.0 nil ALKALINE SILICATE (84% POWDER) nil 3.5 nil nil nil nil (48% SOLUTION) nil nil nil nil nil nil ALUMINIUM SULPHATE HYDRATE nil nil nil nil nil nil CALCITE 23.6 13.0 38.8 23.1 11.0 27.9 SODIUM ORTHOPHOSPHATE nil 5 nil nil nil nil SODIUM PYROPHOSPHATE 4 nil 3 3 3 3 SODIUM TRIPOLYPHOSPHATE 6 nil nil nil nil nil

MINORS AND RESIDUALS BALANCE < -------------BALANCE------------ > TOTAL BAR WATER 9.2 14.7 3.5 6.4 11.0 7.4 PENETROMETER READING (mm) INITIAL (55-60"C) 5.0 6.4 4.2 4.6 3.1 8.7 24 HOUR (RT) 0.01 0.1 0.4 2.0 2.0 2.5 1 WEEK (RT) 0.01 0.01 0.2 1.3 1.7 1.8 Example No: 19 20 21 19A* 22 23 24 25 25% 28% 25% 25% 25% 25% 28% 28% LAS LAS LAS LAS LAS LAS 60/40 60/40 LAS/ LAS/ LES AOS LINEAR ALKYL (Cl2) BENZENE SULPHONATE 25 28 25 25 25 25 16.8 16.8 SODIUM LAURYL ETHER 2EO SULPHATE nil nil nil nil nil nil 11.2 nil ALPHA OLEFIN (C14/16) SULPHONATE nil nil nil nil nil nil nil 11.2 SODIUM TRIPOLYPHOSPHATE 5 5 6 5 6 5 11 11 ALUMINIUM SULPHATE HYDRATE 7.4 7.4 7.4 nil 7.4 7.4 7.4 7.4 SILICA nil nil 3.0 nil 3 nil 3 3 SODIUM CARBONATE 10 10 10 10 2 10 10 10 ADDED WATER 3.3 3.3 2.7 9.1 2.7 1.7 nil nil ALKALINE SILICATE (48% SOLUTION) 6.1 6.1 nil nil nil nil nil nil NEUTRAL SILICATE (38% SOLUTION) nil nil nil nil nil 7.7 nil nil SODIUM PYROPHOSPHATE nil nil 3 nil 3 nil 4 4 SODIUM TRIPOLYPHOSPHATE 4 4 nil 4 nil 4 nil nil CALCITE 33.8 30.8 33.7 41.1 43.9 33.9 26.2 25.7

MINORS AND RESIDUALS < - ---------BALANCE----------------- > TOTAL BAR WATER 10.7 10.7 10.4 10.6 10.4 10.6 9.4 11.2 PENETROMETER READING (mm) INITIAL (55-600C) 4.0 4.6 3.1 12.8 4.0 4.4 4.0 4.2 24 HOUR (RT) 2.2 2.3 1.4 8.2 1.5 2.3 2.6 3.0 1 WEEK (RT) 1.8 1.8 1.2 5.9 1.3 1.9 2.0 2.0 * COMPARATIVE: no silaceous material no polyvalent metal compound.

Example No: 26 27 28 29 30 31 BRANCHED ALKYL (C12) BENZENE SULPHONATE nil 45.0 56.0 64.0 18.0 nil LINEAR ALKYL (C12) BENZENE SULPHONATE 45.0 nil nil nil nil 55.0 COCONUT PRIMARY ALCOHOL SULPHATE nil nil nil nil 27.0 nil SODIUM TRIPOLYPHOSPHATE 6.0 6.0 6.0 6.0 6.0 6.0 ALUMINIUM SULPHATE HYDRATE 7.4 7.4. 8.8 7.4 7.0 10.0 SILICA 3.0 3.0 3.5 3.0 3.0 4.0 SODIUM CARBONATE 10 10 11.5 7.5 10 10 CALCITE 19.3 18.1 nil nil 19.3 2.9 SODIUM PYROPHOSPHATE 3.0 3.0 3.0 3.0 3.0 3.0

MINORS AND RESIDUALS < BALANCE - -- > TOTAL BAR WATER 4.6 4.7 5.7 5.2 4.6 6.0 PENETROMETER READING (mm) INITIAL (55-60"C) 8.5 3.8 4.0 3.7 8.1 8.5 24 HOUR (RT) 2.2 0.1 0.2 0.6 1.1 2.8 1 WEEK (RT) 1.5 0.1 0.1 0.4 0.5 1.6 Example No: 32 32A 32B* 32C* NO NO AL SULPHATE SILICA LINEAR ALKYL (C12) BENZENE SULPHONATE 25 25 25 25 SODIUM TRIPOLYPHOSPHATE 3 nil 3 5 ALUMINIUM SULPHATE HYDRATE 7.4 7.4 nil 7.4 SILICA 3 3 3 nil ADDED WATER 6.5 6.0 9.1 6.5 SODIUM CARBONATE 10 10 10 10 SODIUM TRIPOLYPHOSPHATE 6.0 nil 6.0 4.0 CALCITE 36.9 43.1 41.6 36.9

MINORS AND RESIDUALS < BALANCE < ---------------BALANCE--------------- > TOTAL BAR WATER 10.6 10.1 10.1 10.6 PENETROMETER READING (mm) INITIAL (55-60"C) 3.7 5.4 12.3 7.6 24 HOUR (RT) 1.7 3.0 3.5 4.2 1 WEEK (RT) 1.4 2.6 3.2 3.0 * COMPARATIVE Example No: 33 34 LINEAR ALKYL (C12) BENZENE SULPHONATE 25 25 SODIUM TRIPOLYPHOSPHATE 5 5 MAGNESIUM SULPHATE HYDRATE 7.4 BORIC ACID - 4.1 SILICA 3.0 3.0 SODIUM CARBONATE 10.0 10.0 ADDED WATER 5.0 5.0 SODIUM TRIPOLYPHOSPHATE 4.0 4.0 CALCITE 36.1 39.4

MINORS AND RESIDUALS < ----BALANCE---- > TOTAL BAR WATER 9.3 5.5 PENETROMETER READING (mm) INITIAL (55-60 C) 8.9 12.1 24 HOUR (RT) 2.8 3.4 1 WEEK'(RT) 1.8 1.9 Example No: 35 36 1 37 38 39 LINEAR ALKYL (C12) BENZENE SULPHONATE 25 25 25 25 25 25 SODIUM TRIPOLYPHOSPHATE 3 - 3 - 3 - ALUMINIUM SULPHATE HYDRATE 7.4 7.4 7.4 7.4 - - MAGNESIUM SULPHATE HYDRATE - - - - - 7.4 SILICA 3 3 3 3 3 3 SODIUM CARBONATE 10 10 10 10 10 10 ADDED WATER 6 6 6 6 6 6 ALUMINIUM SULPHATE HYDRATE - - - - 7.4 KAOLIN 13.8 13.8 - - - CALCITE 19.8 19.8 33.7 36.7 38.0 33.6 SODIUM TRIPOLYPHOSPHATE 6 9 3 3 3 9 SODIUM PYROPHOSPHATE - - 3 3 3 ADDED WATER 2.3 1.3 1.3 1.3 - 0.7

MINORS AND RESIDUALS < BALANCE < -------------BALANCE------------ > TOTAL BAR WATER 12.5 11.5 11.5 11.3 10 11.5 PENETROMETER READING (mm) INITIAL (55-60 C) 3.4 7.9 4.1 8.4 5.5 7.4 1 HOUR (RT) 1.7 4.3 1.5 4.6 4.5 24 HOUR (RT) 1.7 3.3 1.4 2.8 2.1 2.9 48 HOUR (RT) 2.2 2.4 1.8 2.3 1 WEEK (RT) 1.3 1.6 1.2 1.7 1.5 1.8

Claims

Claims 1. A method of making detergent laundry bars containing anionic detergent active, detergency builder and other ingredients, in which method a plurality of components including the detergent active and builder are mixed together and the mixture is formed into bars characterised by mixing at least one component of a two-component hardening system with the acid form of at least some detergent active prior to neutralisation thereof and incorporating the other component of the said system before or after the neutralisation, the said two components being a polyvalent metal compound and a silaceous material with the proviso that if silaceous material is mixed in before the neutralisation and the polyvalent metal compound is added after neutralisation, then the metal thereof is aluminium.
2. A method as claimed in claim 1 characterised by first mixing the polyvalent metal compound with the acid form of at least some of the detergent prior to neutralisation thereof.
3. A method as claimed in claim 1 or claim characterised by mixing the silaceous material after neutralisation.
4. A method as claimed in claim 1 characterised by mixing the silaceous material before neutralisation.
5. A method as claimed in claim 4 characterised by mixing the polyvalent metal compound before neutralisation.
6. A method as claimed in claim 4 characterised by mixing an aluminium compound after neutralisation.
7. A method as claimed in any preceding claim characterised by the mixing of a water soluble metal phosphate into the mixture prior to the mixing of both of the components of the hardening system.
8. A method as claimed in claim 7 characterised by mixing the water soluble metal phosphate with the acid form of at least some of the detergent active prior to neutralisation.
9. A detergent laundry bar produced by a method as claimed in any of the preceding claims.