CN112585252B

CN112585252B - Functionalized inorganic for improved delivery of benefit agents to fabrics

Info

Publication number: CN112585252B
Application number: CN201980053448.0A
Authority: CN
Inventors: K·阿查尔亚; S·S·希巴雷; A·萨卡; N·苏布拉马尼亚姆
Original assignee: Unilever IP Holdings BV
Current assignee: Unilever IP Holdings BV
Priority date: 2018-08-14
Filing date: 2019-08-07
Publication date: 2022-04-12
Anticipated expiration: 2039-08-07
Also published as: ZA202100630B; CN112585252A; EP3837339B1; BR112021002702A2; EP3837339A1; PH12021550177A1; WO2020035378A1

Abstract

The present invention relates to a laundry detergent composition comprising benefit agent-containing delivery particles, wherein at least 90% of the particles are less than about 20 μm, wherein said particles comprise at least 70 wt% inorganic material and from 0.1 to 20 wt% of at least one benefit agent, and wherein said particles are prepared by co-precipitating said inorganic material in situ in the presence of at least one benefit agent. The present invention also relates to a method for imparting a desired benefit to a fabric comprising the step of contacting the fabric with an aqueous solution comprising the aforementioned laundry detergent composition comprising a benefit agent delivery particle.

Description

Functionalized inorganic for improved delivery of benefit agents to fabrics

Technical Field

The present invention relates to compositions comprising insoluble inorganic delivery particles incorporating at least one benefit agent for improved delivery of the benefit agent to fabrics. The invention also relates to a method for preparing such particles, and to a method for treating a fabric with such a composition.

Background

On average, laundry detergent compositions may contain more than 30 different actives. Benefit agents are commonly added to laundry detergent compositions, whether for domestic or industrial use. In the case of laundry detergent powders, the benefit agent may be mixed with the detergent composition or adsorbed onto the surface of the particle or mixed with the particle before the particle is mixed into the laundry detergent powder composition.

Most of these actives and/or benefit agents are not effectively utilized for their delivery to the fabric, but are wasted along with the drained wash liquor. This sub-optimal delivery of actives and/or benefit agents may be due to dilute concentrations, harsh wash conditions, competition between actives for deposition onto fabrics, to name a few.

For example, shading dyes are often added to laundry detergent compositions to overcome the undesirable yellowing of white fabrics and to impart a favorable hue to the fabrics treated thereby. However, when incorporated into laundry detergent compositions by themselves, the hueing dye tends to go into solution immediately rather than onto the fabric. Most of the dissolved hueing dye flows away along the drain with the wash liquor, and very little dye is deposited on the fabric. Thus, a very small fraction of the hueing dye included in the detergent composition is used for its intended purpose.

One way to overcome this low performance disadvantage is to increase the concentration of benefit agents in the laundry detergent composition. However, this is not the most feasible solution due to higher consumer costs and the environmental impact of overdosing.

US2008/0207476 discloses particles containing carbonate, sulphate, perfume and layered silicate, said particles having a ratio of-1: 2 to a combination of carbonate and sulphate. The particles having the desired fragrance characteristics are used in detergents, fabric softeners and textile treatment. U.S. patent No. 6,133,215(CIBA, published 10/17/2000) discloses a fabric whitener in the form of white crystals, which is obtained when a polyol such as glycerol, ethylene glycol and/or other polyols is added to a solution of the fabric whitener in water or ethanol. Cyclodextrins are disclosed as adsorptive fillers/carriers and are added as solid materials during processing. The process of us patent No. 6,133,215 has been found to have some disadvantages including agglomeration and clumping of the cyclodextrin as it is added to the reaction vessel. The material obtained by the process of us patent No. 6,133,215 is not suitable for incorporation into detergent compositions.

Accordingly, there is a need for laundry treatment compositions comprising benefit agents which deposit onto fabrics while exhibiting delayed leaching kinetics, thereby ensuring effective utilization and more uniform distribution of the benefit agent on the fabric to impart the desired benefit to the treated fabric without causing undesirable effects.

It is therefore an object of the present invention to provide a laundry composition comprising benefit agent-containing delivery particles which exhibit delayed leaching kinetics of benefit agents incorporated into such particles in aqueous solutions of the aforementioned laundry compositions.

It is another object of the present invention to provide a composition that maximizes the utilization of benefit agents in laundry formulations to save costs and reduce the waste of benefit agents.

It is yet another object of the present invention to enable efficient delivery of benefit agents and thus uniform distribution of benefit agents.

Surprisingly, it has been found that the above objects can be achieved by a laundry detergent composition comprising a benefit agent delivery particle, wherein at least 90% of the particles are smaller than 15 to 20 μm, wherein the particle comprises at least 70 wt% of insoluble inorganic material; and 0.01 to 30 wt% of at least one benefit agent, and wherein the benefit agent delivery particles are prepared by co-precipitating the inorganic insoluble material in situ in the presence of at least one benefit agent.

Disclosure of Invention

Accordingly, the present invention provides a laundry detergent composition comprising a benefit agent delivery particle, wherein at least 90% of the particles are less than 20 μm, wherein the particles comprise at least 70 wt% insoluble inorganic material and from 0.01 to 30 wt% of at least one benefit agent, and wherein the particles are prepared by co-precipitating the inorganic insoluble material in situ in the presence of at least one benefit agent. Preferably, at least 90% of the particles have a size in the range of 15 μm to 20 μm.

It has been surprisingly found that the above-described particles formed by co-precipitating insoluble inorganic materials in situ in the presence of at least one benefit agent results in the benefit agent being incorporated or embedded into the particles thus formed. Further, incorporation of a benefit agent-containing delivery particle formed by the foregoing process in a laundry detergent composition in a specific amount not only delivers an enhanced benefit, but also reduces the need for the amount of benefit agent needed to obtain an enhanced action or benefit, as compared to laundry detergent compositions comprising a benefit agent adsorbed on the surface of a carrier particle or laundry detergent compositions comprising a benefit agent as such blended into the laundry detergent composition.

Thus, the compositions of the present invention not only provide the advantages of uniform distribution of benefit agents and the advantages of delivery enhanced benefits, but also achieve said advantages by utilizing significantly lower amounts of benefit agents, thereby reducing overall cost.

Without intending to be bound by theory, it is believed that incorporating at least one benefit agent into insoluble inorganic particles (wherein at least 90% of the particles are less than about 15 to 20 μm) during the in situ preparation of these particles delays the leaching of the benefit agent from the particles, resulting in effective and efficient deposition of the benefit agent onto the fabric during the laundry washing process.

Accordingly, the present invention provides laundry detergent compositions comprising benefit agent-containing delivery particles which provide improved dissolution characteristics of the benefit agent. The improved benefit agent dissolution profile ensures uniform distribution of the benefit agent on fabrics treated with the aforementioned compositions. In a second aspect, the present invention provides a method of making a benefit agent containing delivery particle comprising the steps of: precipitating the inorganic material in situ; and adding at least one benefit agent during in situ precipitation of the inorganic material; wherein the benefit agent is incorporated or embedded into the formed particles.

The benefit agent-containing inorganic delivery particle formed by the process of the present invention is incorporated into a surfactant-containing laundry detergent composition matrix powder.

In a third aspect, the present invention provides a method of imparting a desired benefit to a fabric comprising the step of contacting the fabric with an aqueous solution of a laundry detergent composition comprising a benefit agent-containing delivery particle of the present invention, wherein at least 90% of the particles are less than 20 μm, wherein the particles comprise at least 70 wt% inorganic material and from 0.01% to 30 wt% of at least one benefit agent, and wherein the particles are prepared by in situ precipitation of the inorganic material in the presence of at least one benefit agent. Preferably, at least 90% of the particles have a size in the range of 15 μm to 20 μm.

In yet another aspect, the present invention also relates to a composition comprising a benefit agent-containing delivery particle having a size of less than about 20 μm, wherein said particle comprises at least 70 wt% inorganic material and 0.01 to 30 wt% of at least one benefit agent.

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the invention may be used in any other aspect of the invention. The word "comprising" is intended to mean "including", but not necessarily "consisting of. In other words, the listed steps or options need not be exhaustive. It should be noted that the examples given in the following description are intended to illustrate the present invention, and are not intended to limit the present invention to those examples per se. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". Numerical ranges expressed in "x to y" format should be understood to include x and y. When multiple preferred ranges are described in the format "x to y" for a particular feature, it is to be understood that all ranges combining the different endpoints are also contemplated.

Detailed Description

The laundry detergent compositions herein are used to treat laundry items. Such compositions may be in solid form (either in the form of tablets or granules). Preferably, the laundry detergent composition herein is a granular laundry detergent composition.

Surfactant-containing laundry detergent composition matrix powders are used herein to describe all intermediates of the fabric treatment composition prior to the addition of the benefit agent-containing delivery particle of the present invention to a laundry detergent composition.

The present invention provides a laundry detergent composition for improved delivery of benefit agents to fabrics, the composition comprising: a benefit agent containing delivery particle, wherein the benefit agent containing delivery particle comprises an insoluble inorganic material and at least one benefit agent. The composition preferably comprises other optional ingredients.

Preferably, the insoluble inorganic material has a solubility in water of 20mg/L or less at 25 ℃, more preferably, the insoluble inorganic material has a solubility in water of 15mg/L or less at 25 ℃.

Benefit agent

The composition comprises at least one benefit agent. The benefit agent may be selected from polymers, bleaches, optical brighteners, hueing agents, perfumes, or combinations thereof.

Polymer and method of making same

Suitable polymers include carboxylate polymers, soil release polymers, anti-redeposition polymers, cellulosic polymers, care polymers, and any combination thereof.

The composition may comprise a carboxylate polymer, such as a maleate/acrylate random copolymer or a polyacrylate homopolymer. Suitable carboxylate polymers include polyacrylate homopolymers having a molecular weight of 4,000Da to 9,000Da, maleate/acrylate random copolymers having a molecular weight of 50,000Da to l00,000Da or 60,000Da to 80,000 Da. Another suitable carboxylate polymer is a copolymer comprising: (i) from 50 to less than 98 weight percent structural units derived from one or more carboxyl-containing monomers; (ii) from 1 to less than 49 weight percent structural units derived from one or more monomers comprising a sulfonate moiety; and (iii)1 to 49 wt% of structural units derived from one or more types of ether bond-containing monomers selected from the group consisting of monomers represented by formulas (I) and (II):

formula (I):

wherein in formula (I), R_oRepresents a hydrogen atom or CH₃Group, R represents CH₂Radical, CH₂CH₂A group or a single bond, X represents a number from 0 to 5, with the proviso that when R1 is a single bond, X represents a number from 1 to 5 and R1 is a hydrogen atom or a C1-C20 organic group;

formula (II)

Wherein in formula (II), Ro represents a hydrogen atom or CH₃Group, R represents CH₂Radical, CH₂CH₂A group or a single bond, X represents a number from 0 to 5, and R1 is a hydrogen atom or a C1-C20 organic group. It may be preferred that the polymer has a weight average molecular weight of at least 50kDa, or even at least 70 kDa.

Soil release polymers

The composition may comprise a soil release polymer. Suitable soil release polymers have a structure as defined in (I), (II) or (III):

(I)-[(OCHR1-CHR2)a-O-OC-A r-CO-]d

(II)-[(OCHR3-CHR4)b-O-OC-sAr-CO-]e

(III)-[(OCHR⁵-CHR⁶)_c-OR⁷]_f

wherein:

a. b and c are 1 to 200; d. e and f are 1 to 50;

ar is 1, 4-substituted phenylene;

sAr is SO substituted in the 5-position₃1, 3-substituted phenylene substituted with Me;

me is Li, K, Mg/2, Ca/2, Al/3, ammonium, mono-, di-, tri-or tetraalkylammonium, wherein the alkyl is C1-C18 alkyl or C2-C10 hydroxyalkyl, or mixtures thereof;

r1, R2, R3, R4, R5 and R6 are independently selected from H or C1-C18 n-or iso-alkyl; and R7 is a linear or branched C1-C18 alkyl group, or a linear or branched C2-C30 alkenyl group, or a cycloalkyl group having 5-9 carbon atoms, or a C6-C30 aryl group, or a C6-C30 arylalkyl group. Suitable soil release polymers are those made by Clariant and

polymer series,

SRN240 and

SRA 300. Other suitable soil release polymers are those made by Solvay and others

Sold in series of polymers, e.g.

SF2 and

anti-redeposition polymers

Suitable anti-redeposition polymers include polyethylene glycol polymers and/or polyethyleneimine polymers. Suitable polyethylene glycol polymers include random graft copolymers comprising: (i) a hydrophilic backbone comprising polyethylene glycol; and (ii) a hydrophobic side chain selected from the group consisting of: C4-C25 alkyl, polypropylene, polybutylene, vinyl esters of saturated C1-C6 monocarboxylic acids, C1-C6 alkyl esters of acrylic or methacrylic acid, and mixtures thereof. Suitable polyethylene glycol polymers have a polyethylene glycol backbone with randomly grafted polyvinyl acetate side chains. The average molecular weight of the polyethylene glycol backbone may be in the range of 2,000Da to 20,000Da, or in the range of 4,000Da to 8,000 Da. The molecular weight ratio of the polyethylene glycol backbone to the polyvinyl acetate side chains may be in the range of 1:1 to 1:5, or 1:1.2 to 1: 2. The average number of grafting sites per ethylene oxide unit may be less than 1 or less than 0.8, the average number of grafting sites per ethylene oxide unit may be in the range of 0.5 to 0.9, or the average number of grafting sites per ethylene oxide unit may be in the range of 0.1 to 0.5 or 0.2 to 0.4. A suitable polyethylene glycol polymer is Sokalan HP 22. Suitable polyethylene glycol polymers are described in WO 0S/007320.

Cellulose polymers

Suitable cellulosic polymers are selected from alkyl celluloses, alkyl alkoxyalkyl celluloses, carboxyalkyl celluloses, alkyl carboxyalkyl celluloses, sulfoalkyl celluloses, more preferably from carboxymethyl cellulose, methyl hydroxyethyl cellulose, methyl carboxymethyl cellulose and mixtures thereof.

Suitable carboxymethyl celluloses have a degree of carboxymethyl substitution of 0.5 to 0.9 and a molecular weight of 100,000Da to 300,000 Da. Suitable carboxymethylcellulose have a degree of substitution of greater than 0.65 and a degree of blockiness (degree of blockinee) of greater than 0.45, for example as described in WO 09/154933.

Care polymers

Suitable care polymers include cationically modified or hydrophobically modified cellulosic polymers. Such modified cellulose polymers may provide anti-wear benefits and dye lock benefits to the fabric during the wash cycle. Suitable cellulosic polymers include cationically modified hydroxyethyl cellulose. Other suitable care polymers include dye-locking polymers, such as condensation-polymerized oligomers produced by condensation of imidazole and epichlorohydrin, preferably in a ratio of 1:4: 1. Suitable commercially available dye-locking polymers are

FDI (cognis). Other suitable care polymers include amino-silicones, which can provide fabric feel benefits and fabric shape retention benefits.

Bleaching agent and bleaching catalyst

Suitable bleaching agents include sources of hydrogen peroxide, bleach activators, bleach catalysts, preformed peracids, and any combination thereof.

One particularly suitable bleaching agent comprises a source of hydrogen peroxide in combination with a bleach activator and/or bleach catalyst. Suitable sources of hydrogen peroxide include sodium perborate and/or sodium percarbonate. Suitable bleach activators include tetraacetylethylenediamine and/or alkyloxybenzene sulfonates.

The composition may comprise a bleach catalyst. Suitable bleach catalysts include oxaziridinium bleach catalysts, transition metal bleach catalysts, especially manganese.

Suitable preformed peracids include phthalimido peroxycaproic acid. Preferably, however, the composition is substantially free of preformed peracid. By "substantially free" it is meant that it is not intentionally added.

Optical brightening agent

Suitable optical brighteners include: distyrylbiphenyl compounds, e.g.

CBS-X, diaminostilbene disulfonic acid compounds, e.g.

DMS Pure Xtra and

HRH, and pyrazoline compounds, such as Blank:

SN, and coumarin compounds, e.g.

SWN. Preferred whitening agents are: 2- (4-styryl-3-sulfophenyl) -2H-naphtho [1,2-d]Triazole sodium, 4' -bis { [ (4-anilino-6- (N-methyl-N-2 hydroxyethyl) amino 1,3, 5-triazin-2-yl)]Amino } stilbene-2, 2 'disulfonic acid disodium salt, 4' -bis { [ (4-anilino-6-morpholino-1, 3, 5-triazin-2-yl)]Disodium amino } stilbene-2, 2 '-disulfonate and disodium 4,4' -bis (2-sulfostyryl) biphenyl. One suitable optical brightener is cjBrightener 260 which may be used in its beta or alpha crystalline form or a mixture of these forms.

Chelating agents

The composition may further comprise a chelating agent selected from the group consisting of diethylenetriaminepentaacetic acid, diethylenetriaminepenta (methylphosphonic acid), ethylenediamine-N ', N' -disuccinic acid, ethylenediamine tetraacetic acid, ethylenediamine tetra (methylenephosphonic acid) and hydroxyethane di (methylenephosphonic acid). Preferred chelating agents are ethylenediamine-N ', N' -disuccinic acid (EDDS) and/or hydroxyethane diphosphonic acid (HEDP). The composition preferably comprises ethylenediamine-N ', N' -disuccinic acid or salts thereof. Preferably, the ethylenediamine-N ', N' -disuccinic acid is in the form of the S, S enantiomer. Preferably, the composition comprises 4, 5-dihydroxy-m-benzenedisulfonic acid disodium salt. Preferred chelating agents may also be used as calcium carbonate crystal growth inhibitors, such as: 1-hydroxyethane diphosphonic acid (HEDP) and salts thereof; n, N-dicarboxymethyl-2-aminopentane-1, 5-dioic acid or its salt; 2-phosphonobutane-1, 2, 4-tricarboxylic acid and salts thereof; and combinations thereof.

Toner for developing electrostatic image

Suitable toners include small molecule dyes, typically falling into the color index (CJ) classifications of acidic, direct, basic, reactive (including hydrolyzed forms thereof) or solvent or disperse dyes, for example, as blue, violet, red, green, or black, and providing, either alone or in combination, a desired shade. Preferred such hueing agents include acid violet 50(AV50), direct violet 9, 66 and 99, solvent violet 13 and any combination thereof. Many toners are known and are suitably described in the art. Suitable toners may be alkoxylated.

Dye transfer inhibitors

Suitable dye transfer inhibiting agents include polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinylpyrrolidone, polyvinyloxazolidone, polyvinylimidazole, and mixtures thereof. Preferred are poly (vinylpyrrolidone), poly (vinylpyridine betaine), poly (vinylpyridine N-oxide), poly (vinylpyrrolidone-vinylimidazole) and mixtures thereof. Suitable commercially available dye transfer inhibitorsIncluding PVP-Kl5 and K30(Ashland),

HP165、HP50、HP53、HP59、HP56K、HP56、HP66(BASF)，

s-400, S403E, and S-100 (Ashland).

Perfume

Suitable perfumes comprise perfume materials selected from the group consisting of: (a) a perfume material having a ClogP of less than 3.0 and a boiling point of less than 250 ℃ (quadrant 1 perfume material); (b) a perfume material having a ClogP of less than 3.0 and a boiling point of 250 ℃ or higher (quadrant 2 perfume material); (c) a perfume material having a ClogP of 3.0 or higher and a boiling point below 250 ℃ (quadrant 3 perfume material); (d) a perfume material having a ClogP of 3.0 or more and a boiling point of 250 ℃ or more (quadrant 4 perfume material); and (e) mixtures thereof.

For perfumes, it may be preferred to be in the form of perfume delivery technology. Such delivery techniques also stabilize and enhance the deposition and release of perfume materials from laundered fabrics. Such perfume delivery technologies can also be used to further increase the duration of perfume release from laundered fabrics. Suitable perfume delivery technologies include: perfume microcapsules, pro-perfumes (pro-perfume), polymer assisted 30 delivery, molecular assisted delivery, fiber assisted delivery, amine assisted delivery, cyclodextrins, starch encapsulation accord, zeolites and other inorganic carriers, and any mixtures thereof. One suitable perfume microcapsule is described in WO 2009/101593.

Inorganic material

The inorganic material of the present invention may be any known inorganic compound. Examples of inorganic compounds which may be particularly suitably used include oxides of metals of groups III, IV or VIII of the periodic Table of the elements, such as aluminum, titanium, zirconium, hafnium, tin, lead, iron, cobalt and nickel; and oxides of semimetals of group III or IV of the periodic table, such as boron, silicon and germanium. (it should be understood that in this specification and the appended claims, the term "metal" also means such a semimetal.)

In one aspect of the present invention, a complex oxide may also be used. Examples include complex oxides of metals of groups III, IV or VIII of the periodic Table of the elements with each other, and complex oxides of the above metals with metals of group I, II or V. There is no particular limitation on the metal selected from the group consisting of I, II th and V group metals in the periodic table, but lithium, sodium, potassium, magnesium, calcium, strontium, barium, phosphorus, antimony, bismuth, vanadium, niobium and tantalum are generally preferred. Generally, in the above-mentioned composite oxide, the metal component of group III, IV or VIII of the periodic table is preferably the main component. Composite oxides containing at least 80 mol% of these metals are particularly preferred.

As the inorganic compound constituting the inorganic material, metal carbonates such as calcium carbonate and magnesium carbonate and metal sulfates such as barium sulfate and strontium sulfate can also be used. Preferably, the inorganic material is calcium carbonate.

In yet another aspect of the invention, the hydrophilic material of the invention is modified by a hydrophobic coating. Non-limiting examples of hydrophobic coatings are fatty acids, silicones, glycerides, esters, surfactants.

Laundry detergent compositions

Surface active agent

The laundry detergent compositions of the present invention comprise an anionic surfactant or a mixture of anionic surfactants. Anionic surfactants are included in the compositions to provide the primary cleaning action by emulsifying the oil attached to the substrate. Any non-soap anionic surfactant known in the art for use in laundry detergents may be used herein. Generally, these surfactants are described in well-known textbooks such as "Surface Active Agents", Vol.1, Schwartz & Perry, Interscience 1949; vol 2, Schwartz, Perry & Berch, Interscience 1958 and/or the latest version of "McCutcheon's Emulsifiers and Detergents", published by Manufacturing conditioners Company, or "Tenside-Taschenbuch", H.Stache, 2 nd edition, Carl HauserVerlag, 1981.

One suitable class of anionic surfactants are the water-soluble salts, in particular the alkali metal (e.g. sodium or potassium), ammonium and alkylolammonium salts of organic sulfuric monoesters and sulfonic acids (condensation products thereof having a branched or straight-chain alkyl group in their molecular structure and an alkyl moiety containing from 8 to 22 carbon atoms or alkylaryl groups containing from 6 to 20 carbon atoms).

Preferred anionic surfactants include higher alkyl aromatic sulfonates such as higher alkyl benzene sulfonates containing from 6 to 20 carbon atoms in the alkyl group, which may be straight or branched, particularly exemplified by higher alkyl benzene sulfonates or higher alkyltoluene, xylene or phenol sulfonates, alkylnaphthalene sulfonates, dipentylnaphthalene sulfonates and dinonylnaphthalene sulfonates; alkyl sulfates containing from 8 to 22 carbon atoms and alkyl ether sulfates containing from 1 to 10 ethylene oxide or propylene oxide units per molecule, preferably from 2 to 3 ethylene oxide units.

Non-limiting examples of anionic surfactants include any common anionic surfactant, such as linear or modified, e.g., branched alkyl benzene sulfonates, alkyl poly (ethoxylates), sodium lauryl ether sulfate, methyl ester sulfonates, primary alkyl sulfates, or mixtures thereof.

The non-soap anionic surfactant is present in the detergent composition at a concentration of from 5 to 60%, preferably not less than 10%, more preferably not less than 12%, still more preferably not less than 15%, but generally not more than 40%, preferably not more than 35%, or even not more than 30% by weight of the total composition.

The anionic surfactant of the present invention may be combined with another surfactant, typically selected from nonionic, cationic, amphoteric or zwitterionic surfactants.

In view of the anionic character of anionic surfactants, cationic, amphoteric or zwitterionic surfactants are added at a concentration that does not interfere with the performance of the composition.

Suitable nonionic surfactants include commercially known water-soluble aliphatic ethoxylated nonionic surfactants including primary and secondary aliphatic alcohol ethoxylates. This includes condensation products of higher alcohols (e.g., alkanols containing from about 8 to 16 carbon atoms in a straight or branched chain structure) with from about 4 to 20 moles of ethylene oxide, such as lauryl or myristyl alcohol with about 10 moles of Ethylene Oxide (EO), tridecyl alcohol with from about 6 to 15 moles of EO, myristyl alcohol with about 10 moles of EO per mole of myristyl alcohol, condensation products of EO with some (a cut of) coconut fatty alcohols of a mixture of fatty alcohols containing alkyl chains varying between 10 and about 14 carbon atoms in length, and wherein the condensates contain about 6 moles of EO per mole of total alcohol or about 9 moles of EO per mole of alcohol, and tallow alcohol ethoxylates containing from 6EO to 11EO per mole of alcohol.

Examples of the foregoing nonionic surfactants include, but are not limited to, Neodol (trade mark, from Shell) ethoxylates, which are higher aliphatic primary alcohols containing about 9 to 15 carbon atoms, such as C9 to C11 alkanols (Neodol 91-8 or Neodol 91-5) condensed with 4 to 10 moles of ethylene oxide, C12-13 alkanols (Neodol 23-6.5) condensed with 6.5 moles of ethylene oxide, C12-15 alkanols (Neodol 25-12) condensed with 12 moles of ethylene oxide, C14-15 alkanols (Neodol 45-13) condensed with 13 moles of ethylene oxide, and the like. Such ethoxamers have HLB (hydrophobic lipophilic balance) values of about 8 to 15 and give good O/W emulsification, whereas ethoxamers with HLB values below 7 contain less than 4 ethylene oxide groups and tend to be poor emulsifiers and poor detergents.

Suitable amphoteric surfactants include derivatives of aliphatic secondary and tertiary amines containing an alkyl group of 8 to 18 carbon atoms and an aliphatic radical substituted with an anionic water-solubilizing group, such as sodium 3-dodecylaminopropionate, sodium 3-dodecylaminopropanesulfonate and sodium N-2-hydroxydodecyl-N-methyltaurate.

Suitable cationic surfactants are quaternary ammonium salts according to the invention, characterized in that the ammonium salt has the general formula: R1R2R3R4N + X-, wherein R1 is C12 to C18 alkyl, R2, R3, and R4 are each independently C1 to C3 alkyl, and X is an inorganic anion. R1 is preferably a C14 to C16 straight chain alkyl, more preferably C16. R2-R4 are preferably methyl. The inorganic anion is preferably selected from halide, sulfate, hydrogen sulfate or OH-.

For the purposes of the present invention, quaternary ammonium hydroxides are considered to be quaternary ammonium salts. More preferably, the anion is a halide or sulfate, most preferably chloride or sulfate. Cetyl-trimethylammonium chloride is a specific example of a suitable compound and is commercially available in large quantities.

Another type of quaternary ammonium cationic surfactant is the benzalkonium halide class, also known as alkyldimethylbenzyl ammonium halides. The most common type is benzalkonium chloride, also known as alkyldimethylbenzyl ammonium chloride (or ADBAC).

Suitable zwitterionic surfactants include derivatives of aliphatic quaternary ammonium, sulfonium, and phosphonium compounds having an aliphatic group of 8 to 18 carbon atoms and an aliphatic group substituted with an anionic water-solubilizing group, such as 3- (N-dimethyl-N-hexadecylammonium) propane-1-sulfonic acid betaine, 3- (dodecylmethyl sulfonium) propane-1-sulfonic acid betaine, and 3- (cetylmethylphosphonium) ethanesulfonic acid betaine.

When present in the composition, the additional surfactant replaces from 0.5 to 15 wt%, preferably from 5 to 10 wt% of the anionic surfactant.

Builder

The laundry detergent compositions herein preferably also contain a builder, which is preferably a non-phosphate species; thus, the builder herein is preferably selected from aluminosilicate ion exchangers (zeolites), and water-soluble monomeric or oligomeric carboxylic acid sequestrants, such as citric acid, succinic acid, oxydisuccinate (oxydisuccinate) and mixtures of the foregoing.

Other suitable builder materials include alkali metal carbonates, bicarbonates and silicates, organic phosphonates, aminopolyalkylene phosphonates and aminopolycarboxylates, ethylenediaminetetraacetic acid and nitrilotriacetic acid.

Other suitable water-soluble organic salts are homo-or co-polymeric polycarboxylic acids or salts thereof, wherein the polycarboxylic acid comprises at least two carboxyl groups separated from each other by not more than two carbon atoms. Examples of such salts are polyacrylates of MW2000 to 5000 and copolymers thereof with maleic anhydride, such copolymers having a molecular weight of 20,000 to 70,000, especially about 40,000.

In a second aspect, the present invention relates to the preparation of a benefit agent containing delivery particle comprising the steps of: precipitating inorganic particles in situ; and adding a benefit agent during in situ precipitation of the inorganic particles, wherein the benefit agent is incorporated into the formed particles; and adding the formed benefit agent-incorporating inorganic particles to a surfactant-containing laundry detergent composition matrix powder.

Preparation of benefit agent containing delivery particles

The benefit agent containing delivery particles of the present invention are prepared in situ by various process routes.

Preferably, at least one benefit agent is already present in the same medium in which the insoluble inorganic material is present, for example a solution of calcium carbonate.

One such process route for forming the particles of the present invention involves bubbling carbon dioxide gas (which may be distilled off (drive off) during the calcination step) through the milk of lime. Milk of lime may be formed by dissolving calcium oxide or calcium hydroxide in water. The benefit agent may first be dissolved into water before the milk of lime is formed and carbon dioxide is purged through the solution at a specific flow rate. Carbon dioxide dissolves in the liquid to contribute carbonate ions. Since the milk of lime comprises a saturated solution of calcium hydroxide having a pH of about 12, calcium carbonate impregnated with the benefit agent is formed and precipitated out of solution.

Another such process route involves adding ice cold sodium carbonate solution to milk of lime, thereby forming insoluble calcium carbonate and soluble caustic soda. The benefit agent may be present in the milk of lime solution and upon addition of the sodium carbonate solution, calcium carbonate particles are formed which are doped or impregnated with the benefit agent. Alternatively, the benefit agent may be pre-dissolved in the sodium carbonate solution before it is added to the milk of lime.

A third such process route referred to herein involves the reaction of milk of lime with ammonium chloride to form a solution of calcium chloride and ammonium hydroxide. Then, the solution is heated, whereby ammonium hydroxide is decomposed into water and ammonia, and ammonia is distilled out of the solution as a gas. Residual solid impurities that do not react in solution are typically removed by conventional settling processes. The calcium chloride solution is then contacted with a sodium carbonate solution (preferably also free of solid matter), whereby calcium carbonate is precipitated and sodium chloride is formed.

The benefit agent may be pre-dissolved in the calcium chloride solution before the solution is contacted with the sodium carbonate solution. Alternatively, the benefit agent may be pre-dissolved in the sodium carbonate solution prior to contact with the calcium chloride solution. In either embodiment, the calcium carbonate particles with the benefit agent incorporated or impregnated therein are precipitated from solution.

The slurry with the precipitated calcium carbonate particles having the benefit agent embedded within the particles is then filtered, dried and comminuted or spray dried to obtain fine particles. The product from the above process is screened through a screen of the desired size and then the oversized granules are reprocessed with fresh material to further reduce the particle size to the desired range.

An alternative process route for the preparation of calcium carbonate is by reacting alkaline earth metal carbonates with calcium salts of hydrochloric or nitric acid. The source of carbonate may preferably be sodium or potassium ions.

The benefit agent may also be adsorbed onto preformed inorganic insoluble particles. The method includes the step of dissolving the benefit agent in water. Preformed calcium carbonate particles having the desired particle size are added to the same solution to form a slurry. Subsequently, the slurry is mixed for a sufficient time to ensure adsorption of the benefit agent onto the preformed calcium carbonate particles. The slurry is then filtered and dried to give the final particles, or spray dried to remove moisture to give the final particles with the benefit agent adsorbed thereon.

In one aspect of the invention, the inorganic insoluble benefit agent-containing delivery particle is further coated with a hydrophobic coating.

Alternatively, if preformed particles are used, the particles are first coated with a hydrophobic coating prior to mixing with the benefit agent. The coating may be carried out in a fluidized bed, pan granulator, concrete mixer, or the like. This helps to attach the benefit agent to the inorganic particles.

The diameters of benefit agent containing delivery particles obtained by the processing methods described herein were measured using a Malvern Mastersizer. The Malvern Mastersizer works according to the principles of the laser diffraction technique. For irregularly shaped particles, Malvern calculates the diameter using the principle of the Feret diameter method.

The size range of benefit agent containing delivery particles prepared by the process of the present invention is between 1 μm and 20 μm in diameter. Preferably, at least 90% of the particles have a size between 15 and 20 μm.

The benefit agent containing delivery particles of the present invention comprise at least 50 wt% inorganic material. Preferably, the benefit agent containing delivery particle of the present invention comprises at least 70 wt% inorganic material.

The benefit agent containing delivery particles of the present invention comprise between 0.1 wt% to 30 wt% of at least one benefit agent. Preferably, the benefit agent containing delivery particle of the present invention comprises between 0.1 to 20 wt% benefit agent.

The ratio of benefit agent to inorganic material is in the range of 0.1:100 to 20: 100. Preferably, the ratio of benefit agent to inorganic material is from 0.1:100 to 10: 100.

The ratio of laundry detergent composition to benefit agent containing delivery particle is from 100:0.1 to 100: 20. In a preferred embodiment, the ratio of laundry detergent composition to benefit agent containing delivery particle is from 100:0.1 to 100: 10.

In a third aspect, the present invention relates to a method of imparting a desired benefit to a fabric, said method comprising the step of contacting the fabric with an aqueous solution of a laundry detergent composition comprising: benefit agent delivery particles, wherein at least 90% of the particles are less than 20 μm, wherein the particles comprise at least 70 wt% inorganic material and 0.1 to 20 wt% of at least one benefit agent, and wherein the particles are prepared by precipitating the inorganic material in the presence of at least one benefit agent. Preferably, at least 90% of the particles have a size in the range of 15 μm to 20 μm.

Product form

The compositions of the invention may take different physical forms, such as solids, gels or pastes. Preferably, the composition of the invention is a solid. The solid rinse aid composition of the present invention is preferably a shaped solid article (e.g., a bar), a granule, or a powder. Preferably, the composition of the invention is in the form of granules.

The invention is further illustrated by the following non-limiting examples.

Examples

The preparation method comprises the following steps:

the calcium carbonate precipitate may be formed by bubbling carbon dioxide in a calcium hydroxide solution or by reacting sodium carbonate with calcium chloride or both optionally potassium carbonate with calcium chloride. The following reactions represent the above processes, respectively:

Ca(OH)₂+CO₂(g)＝CaCO₃+H₂o … … … reaction No 1.

Na₂CO₃+CaCl₂＝CaCO₃+2NaCl … … reaction No 2.

K₂CO₃+CaCl₂＝CaCO₃+2KCl … … reaction No 3.

In the preparation of the granules, all three reactions for the preparation of calcium carbonate have been used.

In preparing formulations a and B, calcium chloride was dissolved in water together with AV50 dye (benefit agent). To this was added a solution of sodium carbonate (formulation B) or potassium carbonate (formulation A) at a specified flow rate (18 ml/min).

Formulation C was prepared by dissolving AV50 in water, followed by the addition of calcium oxide to form a slurry. Carbon dioxide was purged through the slurry containing calcium oxide and AV50 at a flow rate of 5.4 liters/min.

Formulation 01 or the comparative formulation was prepared by dissolving AV50 in water, followed by the addition of preformed calcium carbonate. The slurry was mixed for 30 minutes.

The final slurry in all of these formulations was filtered, dried and pulverized to give the final granules. The diameter of the final particles was evaluated using a Malvern Mastersizer. These final granules were then physically blended with the Bluton CBUS to give an adjuvant mixture. Details of the formulation of the adjuvant mixture are given below.

A comparison of benefit agent containing delivery particles processed by different routes is mentioned in the table below, where the control is a physical blend of a soluble inorganic carrier and a benefit agent. All options are compared to it. Formulations A, B and C were granular calcium carbonate particles formed in situ with the benefit agent incorporated or embedded within these particles, and formulation 1 had preformed calcium carbonate particles with a particle size distribution within the above range, where the benefit agent was adsorbed only onto the surface of these particles, as opposed to being embedded within the particles.

Leaching characteristics:

generation of calibration maps

To generate a calibration curve, 10mg of AV50 dye was dissolved in 100ml of distilled water, which gave a concentration of 100ppm in the product. The 100ppm stock solution was diluted to prepare AV50 solutions of different concentrations. After preparation, the solution was scanned under UV spectrophotometry. In the spectrophotometer, the range is maintained from 800nm to 400 nm. Lambda of the spectrum was found_maxAt 560 nm. The peak values are obtained from the map to generate a calibration map. The slope is calculated from a line graph.

The method comprises the following steps: the leaching kinetics of the product were measured by adding 0.17g of particles formed by each of the different methods of the invention detailed herein to 1L of distilled water and stirring the water at a constant speed of 100rpm using an overhead stirrer. At regular intervals, the solution was withdrawn by syringe and collected in a Tarson tube. The tube was centrifuged at 1000rpm for 5 minutes, and the supernatant liquid was taken to measure the dye concentration using UV spectrophotometry (UV-sic, Perkin Elmer). A calibration curve was previously generated for measuring the concentration of the dye directly from the graph.

Particle size distribution:

the particle size distribution was measured in a Malvern Mastersizer using the Hydro mode. Water is used as the solvent. The particles were added to an analyzer and sonicated to remove any agglomerates. The particle size distribution is given in the table below.

Wherein D (0.1), D (0.5) and D (0.9) indicate that 10%, 50% and 90% of the total particles have a particle diameter within the specific range. D (4,3) means the volume weighted average of the distribution. When the distribution is not gaussian, D (4,3) is required.

It was observed that the particles prepared via the potassium carbonate or sodium carbonate route (formulations a and B, respectively) were smaller in size as reflected by their D (0.9) values compared to the particles formed via the lime route (formulation C) or preformed particles (comparative). In sodium and potassium, the particle size formed with potassium carbonate is smaller.

Performance evaluation:

the method comprises the following steps: washing experiments were performed in a Terg-o-meter. 500ml of water, kept at a hardness of 6FH by the addition of calcium chloride dihydrate and magnesium chloride hexahydrate, was used. Standard fabric WFK10 was selected for the experiments. Standard OMO detergent powders were used. Fabric cleaning compositions of the present invention comprising benefit agent-containing delivery particles formed by the various processing routes described herein were included at levels of 1.1% and at levels of 0.55%. During the experiment, 20 minutes of soaking, 15 minutes of washing and 2 rinses (2 minutes each) were maintained. The experiment lasted 10 wash cycles. The data are provided in the table below.

After washing, R460 and Lab values (both excluding UV and including UV) were measured using a Macbeth spectrophotometer. The Δ b values (relative to (w.r.t.) untreated fabric) were calculated. A more negative value indicates a higher degree of whiteness. The experiment was also performed at a 50% low particle dose and similar results were obtained.

The following conclusions were made:

■ at 100% inclusion levels, the in situ generated particles treated with potassium carbonate (formulation A) and sodium carbonate (formulation B) gave enhanced whiteness benefits compared to the particle blend and preformed particles.

■ the particles processed by the reaction of sodium and potassium carbonates with calcium chloride are superior in efficiency to the particles formed with the lime route in the in situ generated particles. This is mainly due to the fact that the particle size obtained in the former case is smaller than that obtained in the lime route.

■ at the 50% inclusion level, the particles made with sodium and potassium carbonate may retain better performance than the particles processed by the preformed route or the control.

Claims

1. A laundry detergent composition comprising:

-benefit agent delivery particles, wherein at least 90% of the particles are smaller than 20 μ ι η, wherein the particles comprise at least 70 wt% insoluble inorganic material and 0.1 wt% to 20 wt% of at least one benefit agent, and wherein the particles are prepared by precipitating the insoluble inorganic material in the presence of at least one benefit agent, wherein the insoluble inorganic material is calcium carbonate and the calcium carbonate is prepared by reacting an alkali metal carbonate with a calcium salt of hydrochloric or nitric acid.

2. A laundry detergent composition according to claim 1, wherein the benefit agent is selected from perfumes, shading dyes, dye transfer inhibitors, fabric substantive dyes, fluorescers, optical brighteners, antimicrobials, insect repellents, soil release polymers, fabric softeners, dye fixatives and mixtures thereof.

3. A laundry detergent composition according to claim 2, wherein the antimicrobial agent is selected from antifungal agents.

4. A laundry detergent composition according to any one of claims 1 or 3, wherein the laundry detergent composition comprises:

-1 to 30% by weight of a cationic, anionic, nonionic or amphoteric surfactant;

-10 to 50 wt% of a builder; and

-5 to 50% by weight of a filler.

5. A process for making a benefit agent containing delivery particle wherein at least 90% of said particles are less than 20 μ ι η, wherein said particle comprises at least 70 wt% insoluble inorganic material and from 0.1 wt% to 20 wt% of at least one benefit agent, said process comprising the steps of:

i. precipitating the inorganic particles in situ by reacting a carbonate of an alkali metal with a calcium salt of hydrochloric or nitric acid; and

adding the benefit agent during in situ precipitation of the inorganic particles; wherein the benefit agent is incorporated into the formed particles.

6. A process for making a laundry detergent composition comprising the steps of preparing a benefit agent containing delivery particle according to claim 5 and adding an inorganic particle incorporating said benefit agent to a surfactant containing matrix powder.

7. A method of imparting a desired benefit to a fabric comprising the step of contacting the fabric with an aqueous solution of a laundry detergent composition according to any of claims 1-4.

8. A composition comprising benefit agent containing delivery particles having an average size of less than 20 μ ι η, wherein the particles comprise at least 70 wt% insoluble inorganic material and 0.1 to 20 wt% of at least one benefit agent, wherein the insoluble inorganic material is calcium carbonate and the calcium carbonate is prepared by reacting an alkali metal carbonate with a calcium salt of hydrochloric or nitric acid.