|Title of Invention||
A PARTICULATE LAUNDRY DETERGENT COMPOSITION
|Abstract||A particulate laundr^a detergent composition, comprising-. a major proportion of white or light-coloured particles and a minor proportion of visually contrasting bodies of significantly larger average particle size in at least one dimension than the average particle size of the white or light-coloured particles, the bodies being in the shape of small tablets or pastilles.|
|Full Text||FORM -2
THE PATENTS ACT, 1970 (39 of 1970)
(See Section 10)
HINDUSTAN LEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.
The present invention relates to a particulate laundry detergent for use in laundering fabrics by hand or machine.
BACKGROUND AND PRIOR ART
It is well known to include visually contrasting particles, for example, coloured speckles or noodles, in laundry detergent powders. These may be included as a cue to the consumer, to indicate the presence of some specific ingredient, for example, bleach, or may simply be present to give the product an attractive appearance.
In our co-pending application 71/MUM/2001 there is provided a particulate laundry detergent composition comprising a particulate laundry detergent composition comprising a major proportion of white or light-coloured particles and a minor proportion of visually contrasting particles of material capable of imparting colour and fluorescence to the resulting solution or dispersion when the composition is dissolved or dispersed in water, whereby the composition provides a coloured fluorescent solution or dispersion when dissolved or dispersed in water at a concentration within the range of from 1 to 10 g/1.
Thus the distinctive appearance is carried out into wash liquor itself.
The present inventors now propose the inclusion of contrasting bodies providing a greater visual contrast and impact than previously used speckles and noodles. These bodies can provide strong cues to the consumer, for example, to demonstrate the presence of a beneficial ingredient, even if present only in very small amounts.
US 4 082 682 (Colgate-Palmolive) discloses white or lightly coloured detergent powders containing contrastingly coloured elongated soap particles (noodles). The contrastingly coloured soap particles have length to diameter ratio of 3:1 to 10:1.
The present inventors have found that providing particles in uniform shape of tablets or pastilles provide better cue to the consumer regarding the complexities of the product and is cost effective.
DEFINITION OF THE INVENTION
The present invention provides a particulate laundry-
detergent composition comprising a major proportion of \white
DETAILED DESCRIPTION OF THE INVENTION
The visually contrasting bodies
The detergent compositions of the invention contain visually contrasting bodies. These may or may not contain detergent-functional ingredients.
It is essential that the visually contrasting bodies are significantly larger, in at least one dimension, than the bulk of the particles constituting the detergent composition. Preferably at least one dimension of the visually constrasting bodies, on average, is at least 2 times, preferably at least 5 times and more preferably at least 10 times as large as the average particle diameter of the detergent composition particles.
The visually contrasting bodies should also provide the greatest possible visual contrast, in colour, shape and size, to the bulk of the detergent composition, so that
visual impact is maximised. Because detergent particles are irregularly shaped, the visually contrasting bodies are preferably regular in shape. Because detergent particles have a relatively broad particle size distribution, the visually contrasting bodies are preferably uniform in size. They may, for example, all be of identical size and shape, but that is not essential. More than one size or shape may be present but if so these are preferably discrete and clearly defined rather than forming a continuum.
The visually contrasting bodies are preferably formed of brightly coloured material. Not all bodies need be the same colour.
As previously indicated, the visually contrasting bodies are preferably regular in shape. They may suitably possess a relatively high degree of symmetry. However some aesthetically pleasing shapes may not be highly symmetrical.
The visually contrasting bodies are small coloured tablet-
or pastille-shaped bodies. These may suitably be formed of
coloured compressed detergent ingredients or coloured
compressed detergent base powder- The tablet- or pastille-
shaped bodies may contain specific beneficial ingredients,
or may simply act as cues to indicate that these specific
ingredients are present elsewhere in the formulation.
The visually contrasting bodies need be present only at very low concentrations, for example, 0.02 to 1 wt%, preferably from 0.05 to 0.5 wt%, to make a significant visual impact.
The laundry detergent compositions of the invention also contain other conventional detergent ingredients. Essential ingredients are surfactants (detergent-active compounds) and detergency builders, and other conventional ingredients may optionally be present.
Detergent compositions of the invention may suitably
comprise from 5 to 60 wt% of/one or more dete'rqen^r*^
surfactants/and from 10 to 80 wt% of one or more detergency
builders, and optionally other detergent ingredients to
The detergent compositions will contain, as essential ingredients, one or more detergent active compounds (surfactants) which may be chosen from soap and non-soap anionic, cationic, nonionic, amphoteric and zwitterionic detergent active compounds, and mixtures thereof. Many suitable detergent active compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch.
The preferred detergent active compounds that can be used are soaps and synthetic non-soap anionic and nonionic compounds.
Anionic surfactants are well-known to those skilled in the art,. Examples include alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyl
chain length of C8-C15; primary and secondary alkylsulphates, particularly C8-C15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Sodium salts are generally preferred.
Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C8-C2o aliphatic alcohols ethoxylated with an average of from 1 to 2 0 moles of ethylene oxide per mole of alcohol, and more especially the C10-C15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide).
Cationic surfactants that may be used include quaternary ammonium salts of the general formula R1R2R3R4N+ X¬ wherein the R groups are long or short hydrocarbyl chains, typically alkyl, hydroxyalkyl or ethoxylated alkyl groups, and X is a solubilising cation (for example, compounds in which Rx is a C8-C22 alkyl group, preferably a C8-C10 or C12-C14 alkyl group, R2 is a methyl group, and R3 and R4, which may be the same or different, are methyl or hydroxyethyl groups); and cationic esters (for example, choline esters).
In an especially preferred cationic surfactant of the general formula R1R2R3R4N+ X-, R1 represents a C8-C10 or C12-C14 alkyl group, R2 and R3 represent methyl groups, and R4 presents a hydroxyethyl group.
Amphoteric surfactants, for example, amine oxides, and zwitterionic surfactants, for example, betaines, may also be present.
Preferably, the quantity of anionic surfactant is in the range of from 5 to 50% by weight of the total composition. More preferably, the quantity of anionic surfactant is in the range of from 8 to 3 5% by weight.
Nonionic surfactant, if present, is preferably used in an amount within the range of from 1 to 20% by weight.
The total amount of surfactant present is preferably within the range of from 5 to 60 wt%.
The compositions may suitably contain from 10 to 80%, preferably from 15 to 70% by weight, of detergency builder. Preferably, the quantity of builder is in the range of from 15 to 50% by weight.
The detergent compositions may contain as builder a crystalline aluminosilicate, preferably an alkali metal aluminosilicate, more preferably a sodium aluminosilicate (zeolite).
The zeolite used as a builder may be the commercially available zeolite A (zeolite 4A) now widely used in laundry detergent powders. Alternatively, the zeolite may be maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070B (Unilever) , and commercially available as Doucil (Trade Mark) A24 from Crosfield Chemicals Ltd, UK.
Zeolite MAP is defined as an alkali metal aluminosilicate of zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, preferably within the range of from 0.90 to 1.20.
Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The particle size of the zeolite is not critical. Zeolite A or zeolite MAP of any suitable particle size may be used.
Also preferred according to the present invention are phosphate builders, especially sodium tripolyphosphate. This may be used in combination with sodium orthophosphate, and/or sodium pyrophosphate.
Other inorganic builders that may be present additionally or alternatively include sodium carbonate, layered silicate, amorphous aluminosilicates.
Organic builders that may be present include polycarboxylate polymers such as polyacrylates and acrylic/maleic copolymers; polyaspartates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-di-and trisuccinates, carboxymethyloxysuccinates, carboxy-methyloxymalonates, dipicolinates,
hydroxyethyliminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts.
Organic builders may be used in minor amounts as supplements to inorganic builders such as phosphates and zeolites.
Especially preferred supplementary organic builders are citrates, suitably used in amounts of from 5 to 3 0 wt %, preferably from 10 to 25 wt %; and acrylic polymers, more especially acrylic/maleic copolymers, suitably used in amounts of from 0.5 to 15 wt %, preferably from 1 to 10 wt%.
Builders, both inorganic and organic, are preferably present in alkali metal salt, especially sodium salt, form. Detergent compositions according to the invention may also suitably contain a bleach system, although non-bleaching formulations are also within the scope of the invention.
The bleach system is preferably based on peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, capable of yielding hydrogen peroxide in aqueous solution. Suitable peroxy bleach compounds include organic peroxides such as urea peroxide, and inorganic persalts such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Preferred inorganic persalts are sodium perborate monohydrate and tetrahydrate, and sodium percarbonate. The peroxy bleach compound is suitably present in an amount of from 5 to 35 wt%, preferably from 10 to 25 wt%.
The peroxy bleach compound may be used in conjunction with a bleach activator (bleach precursor) to improve bleaching action at low wash temperatures. The bleach precursor is suitably present in an amount of from 1 to 8 wt%, preferably from 2 to 5 wt%.
Preferred bleach precursors are peroxycarboxylic acid precursors, more especially peracetic acid precursors and peroxybenzoic acid precursors; and peroxycarbonic acid precursors. An especially preferred bleach precursor suitable for use in the present invention is N,N,N',N'-tetracetyl ethylenediamine (TAED).
A bleach stabiliser (heavy metal sequestrant) may also be present. Suitable bleach stabilisers include ethylenediamine tetraacetate (EDTA) and the polyphosphonates such as Dequest (Trade Mark), EDTMP.
The detergent compositions may also contain one or more enzymes. Suitable enzymes include the proteases, amylases, cellulases, oxidases, peroxidases and lipases usable for incorporation in detergent compositions.
Preferred proteolytic enzymes (proteases) are catalytically active protein materials which degrade or alter protein types of stains when present as in fabric stains in a hydrolysis reaction. They may be of any suitable origin, such as vegetable, animal, bacterial or yeast origin. Proteolytic enzymes or proteases of various qualities and origins and having activity in various pH ranges of from 4-12 are available. Proteases of both high and low isoelectric point are suitable.
Other enzymes that may suitably be present include lipases, amylases, and cellulases including high-activity cellulases such as Carezyme ex Novo.
In particulate detergent compositions, detergency enzymes are commonly employed in granular form in amounts of from about 0.1 to about 3.0 wt%. However, any suitable physical form of enzyme may be used in any effective amount.
Antiredeposition agents, for example, cellulose esters and ethers, for example sodium carboxymethyl cellulose, may also be present.
The compositions may also contain soil release polymers, for example sulphonated and unsulphonated PET/POET polymers, both end-capped and non-end-capped, and polyethylene ..glycol/polyvinyl alcohol graft copolymers such as Sokolan (Trade Mark) HP22.
Especially preferred soil release polymers are the
sulphonated non-end-capped polyesters described and claimed,
in WO 95 32997A (Rhodia Chimie) .
Other ingredients that may be present include solvents, hydrotropes, fluorescers, photobleaches, foam boosters or foam controllers (antifoams) as appropriate, sodium carbonate, sodium bicarbonate, sodium silicate, sodium sulphate, calcium chloride, other inorganic salts, flow aids such as silicas and amorphous aluminosilicates, fabric conditioning compounds, and perfumes.
Powders of low to moderate bulk density may be prepared by spray-drying a slurry, and optionally postdosing (dry-mixing) further ingredients. "Concentrated" or "compact" powders may be prepared by mixing and granulating processes,
for example, using a high-speed mixer/granulator, or other non-tower processes. In both types of powder, the visually contrasting bodies may be incorporated by postdosing (dry mixing).
The invention will now be illustrated in further detail by means of the following Examples, in which parts and percentages are by weight unless otherwise stated. Trade marks are indicated by an asterisk.
EXAMPLES 1 to 3
Preparation of small coloured tablets of coloured compressed detergent base powder
A detergent base powder was prepared by conventional spray-drying techniques to the following formulation:
Ingredient weight %
Sodium linear alkylbenzene sulphonate 36.72
Sodium tripolyphosphate 22.18
Sodium alkaline silicate 10.71
Sodium sulphate 15.45
Acrylate/maleate copolymer (Sokalan* CP5 ex BASF) 3.06
Sodium carboxymethyl cellulose 0.57
Water and minor impurities to 100.00
Small coloured tablets were prepared by impregnating the detergent base powder with a suitable dye and pressing isng the plastic cover of a microtitre plate (11.5 x 7.8 cm). The depressions in the cover were filled with coloured powder which was pressed down using a small press. The resulting mini-tablets, about the size of artificial sweetener tablets, were released by bending the cover.
Example 1: red mini-tablets
The detergent powder was impregnated with 1 wt% of Octocolor* Red 7 CaLake C4307 (ex Warner Jenkinson Europe Lts) before the pressing of the mini-tablets.
Example 2: green mini-tablets
The detergent powder was impregnated with 1 wt% of 5206680 Siccomet* Griin P 74260 (ex BASF) .
Example 3: blue mini-tablets with bleach
To the detergent formulation above was added 4 wt% of the bleach N,N'-phthaloylaminoperoxycaproic acid (PAP). The powder was compressed and formed into mini-tablets as described above.
Detergent powder containing mini-tablets
A detergent base powder having the following formulation was prepared by a fluid bed granulation technique:
Ingredient Weight %
Sodium linear alkylbenzene sulphonate 19
Sodium carbonate (light soda ash) 36.3
Sodium tripolyphosphate 34.3
Red, green and blue mini-tablets (Examples 1 to 3) were dry-mixed with the powder to give the following final composition:
Component weight %
Detergent base powder (as above) 99.7
Red mini-tablets (Example 1) 0.1
Green mini-tablets (Example 2) 0.1
Blue mini-tablets with bleach (Example 3) 0.1
The coloured mini-tablets made a strong visual impact despite their low concentration.
1 A particulate laundr^a detergent composition, comprising-.
a major proportion of white or light-coloured particles and a minor proportion of visually contrasting bodies of
significantly larger average particle size in at least one dimension than the average particle size of the white or light-coloured particles, the bodies being in the shape of
small tablets or pastilles.
2 A composition as claimed in claim 1, wherein the
visually contrasting bodies have at least one dimension
which, on average, is at least 2 times, preferably at least
5 times, more preferably at least 10 times as large as the
average particle diameter of the white- or light-coloured
detergent composition particles.
3 A composition as claimed in claim 1 or claim 2, wherein the visually contrasting bodies are of regular shape.
4 A composition as claimed in any preceding claim, wherein the visually contrasting bodies are of uniform size and shape.
5 A composition as claimed in any preceding claim, wherein the visually contrasting bodies are of brightly coloured material.
6. A composition as claimed in any preceding claim, wherein the visually contrasting bodies are of regular three-dimensional shape.
7. A composition as claimed in any preceding claim, wherein the visually contrasting bodies are composed of a coloured compressed detergent ingredient.
8. A composition as claimed in claim 7, wherein the visually contrasting bodies are composed of coloured compressed detergent base.
9. A composition as claimed in any preceding claim, which comprises from 5 to 60 wt% of one or more detergent-active material, from 10 to 80 wt% of one or more detergency builder, from 0.02 to 1 wt% of the visually contrasting bodies, and optionally other detergent ingredients to 100 wt%
10. A particulate laundry detergent composition substantially as hereinbefore described in
Dated this 23rd day of January 2001
|Indian Patent Application Number||73/MUM/2001|
|PG Journal Number||41/2007|
|Date of Filing||23-Jan-2001|
|Name of Patentee||HINDUSTAN LEVER LIMITED|
|Applicant Address||HINDUSTAN LEVER HOUSE, 165/166, BACKBAY RECLAMATION, MUMBAI|
|PCT International Classification Number||N/A|
|PCT International Application Number||N/A|
|PCT International Filing date|