GB2171113A

GB2171113A - Laundry detergent bars

Info

Publication number: GB2171113A
Application number: GB08603565A
Authority: GB
Inventors: Peter James Powers
Original assignee: Unilever PLC
Current assignee: Unilever PLC
Priority date: 1985-02-15
Filing date: 1986-02-13
Publication date: 1986-08-20
Also published as: OA08202A; BR8600613A; PH22030A; GB2171113B; GB8503980D0; IN164296B; GB8603565D0; MY101999A

Abstract

Built laundry bars containing fatty acid ester sulphonates are manufactured by a process which includes admixing with the other bar components a chlorine bleach (preferably hypochlorite) in an amount effective to bleach the fatty acidester sulphonate.

Description

SPECIFICATION Bleaching detergent materials Fieldofinvention This invention relates to the bleaching of fatty acid ester sulphonates for inclusion as a detergent material in built laundry bars. Built laundry bars, which are usableforfabricwashing and cleaning surfaces, are a widely used product in a number of countries.

The provision of fatty acid estersulphonates (FAES) with a good colour is a necessary requirement in the manufacture of a commercial product. This invention is directed to improving the colour of FAES containing built laundry bars to insure such products have a good final colour.

Commercial built detergent bars contain detergent active and detergent builder materials together with optional components, for example abrasives, fillers, perfumes, alkaline salts, for example silicates, and bleaching agents.

General description ofinvention The invention provides a process forthe manufacture of built laundry bars containing from about 5% to about 45% by weight of non soap detergent active material and from about 5% to 60% by weight of detergent builder. The laundry bars will contain at least about 5% by weight of fatty acid (C8 to C22) ester (C1 to C4) sulphonate as all or part of the detergentactive material. In this manufacturing procedure the fatty acid ester sulphonic acid is neutralised and then mixed with the other components,the characterising feature ofthe invention being the addition of an effective bleaching amount of a chlorine bleach with the other components.

The chlorine bleach is preferably an alkali metal or alkaline earth metal hypochlorite, especially sodium hypochlorite butalsothe lithium, calcium or magnesium salt; an N-chloroamine such astrichlorocyanuric acid (TCCA) or sodium dichloroisocyanurate dihydrate (Na DCCA 2H2O); or gaseous chlorine passed into the alkaline mass of mixed components. Two or more different chlorine bleaches may if desired be employed in the process ofthe invention.

As already indicated, hypochloride bleaches are especially preferred. In general a concentrated solution of sodium hypochlorite is preferably used because the amount of water introduced into the product istherebykepttoaminimum. For example, sodium hypochlorite solution is available commercially in some countries at 14% and 10% w/wconcentrations: the former, which has an available chlorine content of 14.5%, is preferred for use in the present invention.

The use of a solid hypochlorite, for example, calcium hypochlorite (bleaching powder), is also feasible to obtainbieaching. However,theuseofthismaterial or the analogous magnesium salt introduces hardness ions into the composition with consequent reduction in the effectiveness of the builder component in the composition.

Fatty acid ester sulphonates have the general formula R1CH(SOM)COOR2 where R1 is a branched, for example, derived from petroleum, or straight chain alkyl group containing from 8 to 22 carbon atoms and R7 is an alkyl group containing 1 to 4 carbon atoms. M isacation providingwatersolublepropertiesforthe detergent active and will usually be selected from ammonium, potassium and sodium. Preferably the level offatty acid estersulphonate in the product bar is above about 10% byweightand more preferably above about 20% by weight.

The process ofthe invention may be utilisedto manufacture bars ofwhich fatty acid ester sulphonate forms eitherthe whole or only part ofthe detergentactive system. Other detergent-active materials that may advantageously be present in bars manufactured in accordance with the invention are listed below under "Components".

The quantity of chlorine bleach utilised is designed to provide optimum bleaching of the ester sulphonate detergent active without providing a residual quantity in the product: the presence of bleach-sensitive adjuncts, for example, fluorescers, requires that there be no free bleach species remaining in the product.

The quantity of bleaching agent required will of course depend on the bleaching agent selected. For sodium hypochlorite (14.5% available chlorine), the preferred amount is from 2 to 46% by weight based on the fatty acid ester sulphonate, for example about 24% by weight. For solid calcium hypochlorite (55% available chlorine), the preferred amount is from 0.4 to 15% by weight, for example, from 9 to 12.5% by weight. For trichlorocyanuric acid (90% available chlorine), the preferred amount is from 0.3 to 8% by weight, for example, from 3.5% to 5.5% by weight If more dilute solutions or impure samples having lower available chlorine contents are used, correspondingly larger amounts will be required.

The product prepared bythis process required less pigment because of its lighter colour and bar odour is reduced; the feel characteristics of the product in use are satisfactory.

Prior literature The bleaching of fatty acid ester sulphonate materials for use in detergent formulations is the subject of a number of literature disclosures. These disclosures are, however, directed to the bleaching of the sulpho- nic acid or sulphonate as a separate component for a detergent composition before the detergent material is mixed with othercomponents. Documentswhich disclose the bleaching of neutralised fatty acid ester sulphonate with hypochlorites are GB 2141 706, GB 2 089793B,US3354187,GB1050534,US3485856,GB 1 063 431, DE 1 234709 and US 3142691 (Henkel).

Components Detergent-active and builder components are well charncterised in detergent bartechnology. These components are described in "Surface Active Agents" by Schwartz and Perry (lnterscience 1949) and Volume II by Schwartz, Perry and Berch (Interscience 1958).

The detergent-active materials usable in the present invention in admixture with fatty acid ester sulphon- ates may be found in the general classes of anionic, nonionic, amphoteric, betaine and zwitterionic actives. Specific examples of detergent-active materials arelinearalkyl benzenesulphonates,alkanesulphonates, secondary alcohol sulphates, branched alkyl benzene sulphonates, alkyl sulphates, olefin sulphonates, monocarboxylic acid salts, ethoxylated alcohols and above all, primary alcohol sulphates.

Especially preferred for use in bars prepared according to the invention are C8-C22 primary alcohol sulphates and linear or branched C8-C15 akylbenzene sulphonates.

Examples of builder components are: water soluble phosphate salts, for example, sodium tripolyphosphate, pyrophosphate and orthophosphate; water soluble carbonates, for example, sodium carbonate, organic builders, for example, sodium nitrilotriacetate, sodium tartrate,trisodium carboxymethyl oxysuccinate, sodium oxydisuccinate, sodium sulphonated long-chain monocarboxylic acids; and ion exchange materials, for example, aluminosilicates.

Other ingredients, for example, silicates such as sodium alkaline silicate, starch, sodium carboxymethyl cellulose, colouring materials, fluorescers, opacifiers, germicides, enzymes, perfumes, bleaching agents and fillers, for example, sodium sulphate, talc, calcite and bentonite, may optionally be present.

Specific description ofthe invention The invention will now be described infurtherdetail in the following non-limiting Examples.

EXAMPLE 1 A laundry bar product with the following composi tionwas prepared: Weight % Coconut fatty acid methyl ester sulphonate (Ksalt) 31 Watersolublecarbonate salts 13 Sodium phosphate builder salts 8 Aluminium sulphate (calculated as anhydrous salt) 4.2 Sodium alkaline silicate 2.9 Sodium hypochloride (as 14% solution) 7.5 Fillers 20 Water 10.0 Minors and impurities 3.4 This product was manufactured using thefollowing process. Fatty acid ester sulphonic acid (29%) and water (2.25%) were mixed for2 minutes and then the kaolin was added and mixed for 2 minutes. Potassium carbonate (9.6% ) was added over a period of time to control the rate of reaction.The neutralisation step took 10 to 15 minutes afterwhich thetemperature of the mix was between 55 and 70"C. Hypochlorite bleach was added and the mixing continued for up to 15 minutes until the dough was an acceptable white colour. Alkaline silicate, sodium carbonate (13.2%) and aluminium sulphate tetradecahydrate were then added sequentially and mixed in, followed by the remaining bar ingredients. In thefinal stages a dispersed blue pigment and a perfume were added and mixed in. After milling. the productwas ultimately extruded in barform.

EXAMPLE 2 A laundry bar product with the following composition was prepared: Weight % Coconut fatty acid estersulphonate (K salt) 21.7 Coconut alkyl sulphate (Na salt) 9.3 Potassium carbonate 4.0 Sodiumalkalinesilicate 2.9 Sodium carbonate 13.2 Aluminium sulphate (calculated as anhydrous salt) 4.2 Trichlorocyanuricacid 0.83 Kaolin 5.0 Sodium phosphate builder salts 8.0 Fillers 19.17 Water 8.5 Minors and impurities 3.1 This product was manufactured using the following process. Fatty acid ester sulphonine acid (21%) and water (2.25%) were mixed for 2 minutes and then the kaolin was added and mixed for 2 minutes. Potassium carbonate (8.4% ) was added over a period of time to control the rate of reaction.The neutralisation step took 10 to 15 minutes after which the temperature of the mix was between 55 and 65 C.The sodium coconut alkyl sulphate was then added and mixed in for3 minutes. Trichlorocyanuric acid, slurried with the same amountofwater,wasthen added and the mixing continued fora further 5 minutes. Alkaline silicate, sodium carbonate (17.0%) and aluminium sulphatetetradecahydrate were then added sequentiallyand mixed in, followed bythe remaining bar ingredients. In the final stages a dispersed blue pigment and a perfume were added and mixed in.

After milling,the productwas ultimately extruded in barform.

EXAMPLE 3 A laundry bar product with the following composition was prepared: Weight % Coconutfattyacid estersulphonate (K salt) 21.7 Coconutalkyl sulphate (Na salt) 9.3 Potassium carbonate 5.0 Sodium alkaline silicate 2.9 Sodium carbonate 5.0 Aluminium sulphate (calculated as anhydrous salt) 4.2 Calcium hypochlorite 2.0 Kaolin 5.0 Sodium phosphate buildersalts 12.0 Fillers 18.9 Water 11.0 Minors and impurities 3.0 This product was manufactured using the following process. Fatty acid ester sulphonic acid (21% ) and water (2.25%) were mixed for 2 minutes and then the kaolin was added and mixed for 2 minutes. Potassium carbonate (9.4%) was added over a period oftime to control the rate of reaction.The neutralisation step took 10 to 15 minutes afterwhich the temperature of the mix was between 55 and 65"C. The sodium coconutalkyl sulphatewasthen added and mixed in for3 minutes. Bleaching powder (calcium hypochlorite), slurried with the same amount of water, was then added and the mixing continued for a further 5 minutes. Alkaline silicate, sodium carbonate (11.2% ) and aluminium sulphate tetradecahydrate were then added and mixed sequentially, followed by the remaining bar ingredients. In the final stages a dispersed blue pigment and a perfumewere added and mixed. After milling, the productwas ultimately extruded in barform.

EXAMPLE 4 A laundry bar product with the following composi tionwas prepared: Weight % Coconut fatty acid ester sulphonate (K salt) 26.35 Coconutalkyl sulphate (Na salt) 4.65 Sodium tripolyphosphate 20.0 Aluminium sulphate (calculated as anhydrous salt) 4.2 Sodium alkaline silicate 2.9 Potassium carbonate 5.0 Sodium carbonate 5.0 Calcite 12.5 Kaolin 5.0 Trichlorocyanuricacid 1.0 Water 10.0 Minor ingredients and impurities 3.4 The product was manufactured using the following process. Fatty acid estersulphonicacid (25.5%) and water (2.25%) were mixed for2 minutes and then kaolin was added and mixed for 2 minutes. Potassium carbonate was added over a period oftime to control the rate of reaction.The neutralisation step took 10 to 15 minutes afterwhich the temperature ofthe mix was between 55 and 65"C. Sodium coconut alkyl sulphate was then added and mixed from 3 minutes. Trichlorocyanuric acid, slurried with the same mass of water, was then added and the mixing continued for a further 5 minutes. Sodium alkaline silicate, sodium carbonate and aluminium sulphate tatradecahydrate were then added and mixed in for 10 minutes, followed by the calcite filler and phosphate builder. In the final stages a dispersed blue pigment and a perfume were added.

Once homogeneous the dough was milled and the productwasextruded in bar form.

EXAMPLE 5 A laundry bar product containing a different phosphate builder, sodium pyrophosphate, was prepared: Weight % Coconut fatty acid ester sulphonate (K salt) 15.5 Coconut alkyl sulphate (Na salt) 15.5 Sodium pyrophosphate 15.0 Aluminium sulphate (calculated as anhydrous salt) 2.1 Sodium alkaline silicate 1.5 Potassium carbonate 7.0 Calcite 23.8 Kaolin 5.0 Trichlorocyanuric acid 0.6 Water 11.0 Minoringredients and impurities 3.0 This product was manufactured using the following process. Fatty acid ester sulphonic acid (15%) and water (1.5%) were mixedfor2 minutes and the kaolin was added and mixedfor2 minutes. Potassium carbonate (10.0%) was added over a period oftime to control the rate of reaction.The neutralisation step took 10 to 15 minutes afterwhich the temperature of the mix was between 55 and 65"C. Sodium coconut alkyl sulphate was then added and mixed for 3 minutes. Trichlorocyanuric acid, slurried with the same mass of water, was then added and the mixing continuedforafurther5 minutes. Sodium silicate, potassium carbonate (3.4%) and aluminium sulphate were then added and mixed in for 10 minutes, followed bythe calcitefillerand phosphate builder. In the final stages dispersed blue pigment and a perfume were added. Once homogeneous the dough was milled and the product was extruded in barform.

EXAMPLE 6 Alaundrybarproductwiththefollowing composi- tion was prepared: Weight % Coconut fatty acid ester sulphonate (K salt) 29.45 Coconut alkyl sulphate (Na salt) 1.5 Sodium tripolyphosphate 6.0 Potassium carbonate 10.0 Sodium carbonate 3.7 Calcite 23.7 Kaolin 10.0 Trichlorocyanuricacid 1.5 Water 10.0 Minoringredientsand impurities 4.15 This product was manufactured using the following process. Fatty acid ester sulphonic acid (28.5%) and water (2.5%) were mixed for 2 minutes and then part of the kaolin (5%) was added and mixed for 2 minutes.

Potassium carbonate (15.7%)wasadded over a period of time to control the rate of reaction. The neutralisation step took 10 to 15 minutes after which thetemperature of the mix was between 55 and 65"C.

Sodium coconut alkyl sulphate was then added and mixed for 3 minutes. Trichlorocyanuric acid, slurried with the same mass of water, was then added and the mixing continued for a furtherS minutes. Sodium carbonate was then added and mixed in for 3 minutes, followed by the calcite filler, the remaining kaolin (5%) and the phosphate builder. In the final stages dispersed blue pigment and a perfume were added. Once homogeneous the dough was milled and the product was extruded in barform.

EXAMPLE 7 A laundry bar containing alkylbenzene sulphonate and a mixed phosphate builder was prepared: Weight % Coconut fatty acid ester sulphonate (Na salt) 24.8 Alkylbenzene sulphonate (Na salt)* 6.2 Sodium pyrophosphate 6.0 Sodiumtripolyphosphate 2.0 Aluminium sulphate (calculated as anhydrous salt) 1.9 Sodium alkaline silicate 1.3 Sodium carbonate 12.0 Calcite 20.4 Kaolin 9.4 Calcium hypochlorite 3.0 Water 8.7 Minor ingredients and impurities 4.3 * branched chain; Oronite (Trade Mark) 56 This product was manufactured using the following process. Alkyl benzene sulphonic acid (6.0%), fatty acid estersulphonic acid (24.0%) and water (2.5%) were mixed for 2 minutes and then kaolin was added and mixed for 2 minutes. Sodium carbonate (14.6%) was added over a period of time to control the rate of reaction. The neutralisation step took 10 to 15 minutes after which the temperature of the mix was between 55 to 65"C. Calcium hypochlorite, slurried with the same mass of water was then added and the mixing continuedforafurther5 minutes. Sodium alkaline silicate, sodium carbonate (5%) and aluminium sulphate were then added and mixed in for 10 minutes, followed bythecalcitefillerand phosphate builder. In the final stages a dispersed blue pigment and a perfume were added. Once homogeneous the dough was milled and the product was extruded in bar form.

Claims

1. A process forthe manufacture of built laundry bars containing from 5% to 45% byweight of non-soap detergent-active material and from 5% to 60% by weight of detergent builderwith fatty acid ester sulphonate forming at least 5% ofthe product, in which process fatty acid estersulphonate is mixed with the other components, and a chlorine bleaching agent is added with the other components in an amount effective to bleach the fatty acid ester sulphonate present.

2. A process as claimed in claim 1, wherein the chlorine bleaching agent is a hypochlorite.

3. A process as claimed in claim 2, wherein the chlorine bleaching agent comprises sodium hypochlorite, used in concentrated aqueous solution form in an amount corresponding to from 2 to 46% by weight (based on the fatty acid ester sulphonate) of a solution having an available chlorine content of 14.5%

4. A process as claimed in claim 2, wherein the chlorine bleaching agent comprises calcium hypochlorite, used in solid form in an amount corresponding to from 0.4 to 15% by weight (based on the fatty acid estersulphonate) of material having an available chlorine content of 55%.

5. A process as claimed in claim 1, wherein the chlorine bleaching agent istrichlorocyanuric acid, used in an amount corresponding to from 0.3 to 8% by weight (based on the fatty acid ester sulphonate) of material having an available chlorine content of 90%.

6. A process as claimed in any one of claims 1 to 5, wherein a C8-C22 primary alkyl sulphateand/ora linear or branched C8-C15 alkylbenzene sulphonate is also mixed with the fatty acid ester sulphonate.

7. A process as claimed in claim 1, carried out substantially as described in any one of Examples 1 to 7 herein.

8. A built laundry bar whenever manufactured by a process as claimed in any one of claims 1 to 7.