EP4526414A1

EP4526414A1 - Concentrated fabric conditioner

Info

Publication number: EP4526414A1
Application number: EP23721621.3A
Authority: EP
Inventors: Dhanalakshmi THIRUMENI; Jayashree Anantharam Vadhyar
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Priority date: 2022-05-19
Filing date: 2023-04-20
Publication date: 2025-03-26
Also published as: WO2023222322A1; CN119173618A

Abstract

A concentrated fabric conditioner formulation comprising: 10 wt.% to 85 wt.% fabric softening active; and a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids.

Description

CONCENTRATED FABRIC CONDITIONER

Field of the Invention

The present invention is in the field of concentrated fabric conditioners. of the Invention

Concentrated fabric conditioners are fabric conditioners containing high levels of fabric softening actives. Such formulations are challenging to formulate as suitable consumer products due to the high levels of actives leading to issues such as stability. One particularly challenging aspect for concentrated formulations is preservation. Many well-known preservatives are either insoluble in non-aqueous solvents or lead to turbidity I precipitation in a concentrated fabric conditioner composition. Fungus such as Aspergillus brasiliensis are particularly important to preserve against. of the Invention

It has been found that by using a preservative combination of at least two ingredients selected from: aromatic alcohols and/or carboxylic acids, a stable formulation can be obtained, and preservation efficacy is improved.

Accordingly in one aspect of the present invention is provided a concentrated fabric conditioner formulation comprising: a) 10 wt.% to 85 wt.% fabric softening active; b) Preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids.

The invention further relates to a method of preserving a concentrated fabric conditioner wherein aromatic alcohol and carboxylic acid are added to the concentrated fabric conditioner.

In a further aspect of the present invention is provided a use of aromatic alcohol and carboxylic acid to preserve a concentrated fabric conditioner. Detailed of the Invention

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 present invention may be utilised in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight/weight percentages unless otherwise indicated. 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 the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

Fabric softening active

The fabric conditioners described herein comprise fabric softening actives. The fabric softening actives are cationic materials. The fabric conditioners described herein preferably comprise quaternary ammonium compounds (QAC).

The QAC preferably comprises at least one chain derived from fatty acids, more preferably at least two chains derived from a fatty acid. Generally fatty acids are defined as aliphatic monocarboxylic acids having a chain of 4 to 28 carbons. Fatty acids may be derived from various sources such as tallow or plant sources. Preferably the fatty acid chains are derived from plants. Preferably the fatty acid chains of the QAC comprise from 10 to 50 wt. % of saturated C18 chains and from 5 to 40 wt. % of monounsaturated C18 chains by weight of total fatty acid chains. In a further preferred embodiment, the fatty acid chains of the QAC comprise from 20 to 40 wt. %, preferably from 25 to 35 wt. % of saturated C18 chains and from 10 to 35 wt. %, preferably from 15 to 30 wt. % of monounsaturated C18 chains, by weight of total fatty acid chains. The preferred quaternary ammonium fabric softening actives for use in compositions of the present invention are so called "ester quats" or ester linked quaternary ammonium compounds. Particularly preferred materials are the ester-linked triethanolamine (TEA) quaternary ammonium compounds comprising a mixture of mono-, di- and tri-ester linked components. Typically, TEA-based fabric softening compounds comprise a mixture of mono, di- and tri ester forms of the compound where the di-ester linked component comprises no more than 70 wt.% of the fabric softening compound, preferably no more than 60 wt.% e.g., no more than 55%, or even no more that 45% of the fabric softening compound and at least 10 wt.% of the monoester linked component.

A first group of quaternary ammonium compounds (QACs) suitable for use in the present invention is represented by formula (I): wherein each R is independently selected from a C5 to C35 alkyl or alkenyl group; R¹ represents a C1 to C4 alkyl, C2 to C4 alkenyl or a C1 to C4 hydroxyalkyl group; T may be either O-CO. (i.e. an ester group bound to R via its carbon atom), or may alternatively be CO-O (i.e. an ester group bound to R via its oxygen atom); n is a number selected from 1 to 4; m is a number selected from 1, 2, or 3; and X- is an anionic counter-ion, such as a halide or alkyl sulphate, e.g. chloride or methylsulfate. Di-esters variants of formula I (i.e., m = 2) are preferred and typically have mono- and tri-ester analogues associated with them. Such materials are particularly suitable for use in the present invention.

Suitable actives include soft quaternary ammonium actives such as Stepantex VT90, Rewoquat WE18 (ex-Evonik) and Tetranyl L1/90N, Tetranyl L190 SP and Tetranyl L190 S (all ex-Kao).

Also suitable are actives rich in the di-esters of triethanolammonium methylsulfate, otherwise referred to as "TEA ester quats".

Commercial examples include Praepagen™ TQL (ex-Clariant), and Tetranyl™ AHT-1 (ex-Kao), (both di-[hardened tallow ester] of triethanolammonium methylsulfate), AT-1 (di-[tallow ester] of triethanolammonium methylsulfate), and L5/90 (di-[palm ester] of triethanolammonium methylsulfate), (both ex-Kao), and Rewoquat™ WE15 (a di-ester of triethanolammonium methylsulfate having fatty acyl residues deriving from C10-C20 and C16-C18 unsaturated fatty acids) (ex-Evonik).

A second group of QACs suitable for use in the invention is represented by formula (II):

(R’ HCH^-CH-TR' X- (II) CHjTR² wherein each R¹ group is independently selected from C1 to C4 alkyl, hydroxyalkyl or C2 to C4 alkenyl groups; and wherein each R² group is independently selected from C8 to C28 alkyl or alkenyl groups; and wherein n, T, and X- are as defined above.

Preferred materials of this second group include 1 ,2 bis[tallowoyloxy]-3- trimethylammonium propane chloride, 1 ,2 bis[hardened tallowoyloxy]-3- trimethylammonium propane chloride, 1 ,2- bis[oleoyloxy]-3-trimethylammonium propane chloride, and 1 ,2 bis[stearoyloxy]-3- trimethylammonium propane chloride. Such materials are described in US 4, 137,180 (Lever Brothers). Preferably, these materials also comprise an amount of the corresponding monoester.

A third group of QACs suitable for use in the invention is represented by formula (III): wherein each R¹ group is independently selected from C1 to C4 alkyl, or C2 to C4 alkenyl groups; and wherein each R² group is independently selected from C8 to C28 alkyl or alkenyl groups; and n, T, and X- are as defined above. Preferred materials of this third group include bis(2-tallowoyloxyethyl)dimethyl ammonium chloride, partially hardened and hardened versions thereof.

A particular example of the third group of QACs is represented the by the formula (IV): A fourth group of QACs suitable for use in the invention are represented by formula (V)

Ri and R2 are independently selected from C10 to C22 alkyl or alkenyl groups, preferably C14 to C20 alkyl or alkenyl groups. X- is as defined above.

The iodine value of the quaternary ammonium fabric conditioning material is preferably from 0 to 80, more preferably from 0 to 60, and most preferably from 0 to 45. The iodine value may be chosen as appropriate. Essentially saturated material having an iodine value of from 0 to 5, preferably from 0 to 1 may be used in the compositions of the invention. Such materials are known as "hardened" quaternary ammonium compounds.

A further preferred range of iodine values is from 20 to 60, preferably 25 to 50, more preferably from 30 to 45. A material of this type is a "soft" triethanolamine quaternary ammonium compound, preferably triethanolamine di-alkylester methylsulfate. Such ester-linked triethanolamine quaternary ammonium compounds comprise unsaturated fatty chains.

If there is a mixture of quaternary ammonium materials present in the composition, the iodine value, referred to above, represents the mean iodine value of the parent fatty acyl compounds or fatty acids of all the quaternary ammonium materials present. Likewise, if there are any saturated quaternary ammonium materials present in the composition, the iodine value represents the mean iodine value of the parent acyl compounds of fatty acids of all of the quaternary ammonium materials present.

Iodine value as used in the context of the present invention refers to, the fatty acid used to produce the QAC, the measurement of the degree of unsaturation present in a material by a method of nmr spectroscopy as described in Anal. Chem., 34, 1136 (1962) Johnson and Shoolery.

A further type of softening compound may be a non-ester quaternary ammonium material represented by formula (VI): R¹

Rl— — ⁺— R² (VI) wherein each R¹ group is independently selected from C1 to C4 alkyl, hydroxyalkyl or C2 to C4 alkenyl groups; R² group is independently selected from C8 to C28 alkyl or alkenyl groups, and X- is as defined above.

Preferably the fabric conditioners of the present invention comprise more than 10 wt. % ester- linked quaternary ammonium compound, preferably more than 15 wt. % ester-linked quaternary ammonium compound, more preferably more than 25 wt. % ester-linked quaternary ammonium compound, most preferably more than 35 wt.% ester-linked quaternary ammonium compound, by weight of the composition. Preferably the fabric conditioners of the present invention comprise less than 85 wt. % ester-linked quaternary ammonium compound, more preferably less than 80 wt. % ester-linked quaternary ammonium compound, most preferably less than 70 wt. % ester-linked quaternary ammonium compound by weight of the composition. Suitably the fabric conditioners comprise 10 to 85 wt. % ester-linked quaternary ammonium compound, preferably 15 to 80 wt.% ester-linked quaternary ammonium compound, more preferably 25 to 70 wt.% ester-linked quaternary ammonium compound and most preferably 35 to 70 wt. % ester-linked quaternary ammonium compound by weight of the composition. Particularly preferred ranges may be 30 to 60 wt.% ester-linked quaternary ammonium compound and 50 to 80 wt.% ester-linked quaternary ammonium compound.

Preservative composition

The concentrated fabric conditioners described herein comprise a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids. Preferably 2 to 5 ingredients selected from aromatic alcohols and/or carboxylic acids, most preferably 2 to 3 ingredients selected from aromatic alcohols and/or carboxylic acids.

The concentrated fabric conditioner compositions preferably comprise 0.01 to 5 wt.% preservative, more preferably 0.05 to 3 wt.% preservative, most preferably 0.1 to 2 wt.% preservative by weight of the composition. The preservative composition may comprise at least two carboxylic acids, two aromatic alcohols or a carboxylic acid and an aromatic alcohol. Preferably the preservative composition comprises at least two carboxylic acids or a carboxylic acid and an aromatic alcohol. More preferably the preservative composition comprises at least a carboxylic acid and an aromatic alcohol. Most preferably the preservative composition contains at least a carboxylic acid and an aromatic alcohol.

The aromatic alcohol may be any chemical compounds containing a hydroxyl group ( — OH) bonded indirectly to an aromatic hydrocarbon group. Preferably the alcohol group is bonded to a hydrocarbon chain of 1 to 10 carbon atoms, which is bonded to the aromatic ring, more preferably 1 to 7 carbon atoms and most preferably 1 to 4 carbon atoms. Particularly preferred aromatic alcohols include benzyl alcohol and phenol ethanol.

The carboxylic acid may be any chemical compounds comprising at least one carboxylic acid group (C(=O)OH). Preferably the carboxylic acid comprises a 1 to 4 carboxylic acid groups, more preferably 1 to 3 carboxylic acid groups. Preferably the carboxylic acid comprises 1 to 10 carbon atoms, preferably 1 to 7, most preferably 1 to 4 carbon atoms. Examples of preferred carboxylic acids include citric and lactic acids. Most preferably the preservative composition comprises lactic acid.

Solvents

The compositions descried herein preferably comprise a solvent. The solvent is non-aqueous. Preferably the solvent is an organic solvent. Preferred organic solvents include hydrocarbons and/or aromatic alcohols. The solvent may comprise a mixture of suitable solvents. Particularly preferred hydrocarbons are hydrocarbons with a carbon chain comprising from 12 to 18 carbons. A particularly preferred aromatic alcohol is benzyl alcohol.

Preferably the composition comprises 5 to 80 wt. % of the solvent described herein. More preferably 10 to 65 wt. % solvent and most preferably 15 to 50 wt. % solvent by weight of the composition. Perfumes

The compositions as described herein preferably comprise perfume. Where present, the compositions preferably comprise 0.1 to 30 wt. % perfume, i.e. free perfume and/or perfume microcapsules. As is known in the art, free perfumes and perfume microcapsules provide the consumer with perfume hits at different points during the laundry process. It is particularly preferred that the compositions of the present invention comprise a combination of both free perfume and perfume microcapsules.

Preferably the compositions of the present invention comprise 0.5 to 30 wt.% perfume materials, more preferably 1 to 20 wt.% perfume materials, most preferably 1 to 15 wt. % perfume materials.

Useful perfume components may include materials of both natural and synthetic origin. They include single compounds and mixtures. Specific examples of such components may be found in the current literature, e.g., in Fenaroli's Handbook of Flavor Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947 by M. B. Jacobs, edited by Van Nostrand; or Perfume and Flavor Chemicals by S. Arctander 1969, Montclair, N.J. (USA). These substances are well known to the person skilled in the art of perfuming, flavouring, and/or aromatizing consumer products.

The compositions of the present invention preferably comprise 0.5 to 20 wt.% free perfume, more preferably 0.5 to 12 wt. % free perfume.

Particularly preferred perfume components are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP or greater than 2.5. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Boiling point is measured at standard pressure (760 mm Hg). Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components.

It is commonplace for a plurality of perfume components to be present in a free oil perfume composition. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components. An upper limit of 300 perfume components may be applied.

The compositions of the present invention preferably comprise 0.5 to 20 wt.% perfume microcapsules, more preferably 0.5 to 12 wt. % perfume microcapsules. The weight of microcapsules is of the material as supplied.

When perfume components are encapsulated, suitable encapsulating materials, may comprise, but are not limited to; aminoplasts, proteins, polyurethanes, polyacrylates, polymethacrylates, polysaccharides, polyamides, polyolefins, gums, silicones, lipids, modified cellulose, polyphosphate, polystyrene, polyesters or combinations thereof. Particularly preferred materials are aminoplast microcapsules, such as melamine formaldehyde or urea formaldehyde microcapsules.

Perfume microcapsules of the present invention can be friable microcapsules and/or moisture activated microcapsules. By friable, it is meant that the perfume microcapsule will rupture when a force is exerted. By moisture activated, it is meant that the perfume is released in the presence of water. The compositions of the present invention preferably comprise friable microcapsules. Moisture activated microcapsules may additionally be present. Examples of a microcapsules which can be friable include aminoplast microcapsules.

Perfume components contained in a microcapsule may comprise odiferous materials and/or pro-fragrance materials.

Particularly preferred perfume components contained in a microcapsule are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP greater than 2.5. Preferably the encapsulated perfume compositions comprises at least 20 wt.% blooming perfume ingredients, more preferably at least 30 wt.% and most preferably at least 40 wt.% blooming perfume ingredients. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Preferably the encapsulated perfume compositions comprises at least 10 wt.% substantive perfume ingredients, more preferably at least 20 wt.% and most preferably at least 30 wt.% substantive perfume ingredients. Boiling point is measured at standard pressure (760 mm Hg). Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components. It is commonplace for a plurality of perfume components to be present in a microcapsule. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components in a microcapsule. An upper limit of 300 perfume components may be applied.

The microcapsules may comprise perfume components and a carrier for the perfume ingredients, such as zeolites or cyclodextrins.

Other ingredients

The compositions for use as described herein may comprise other ingredients of fabric conditioner liquids as will be known to the person skilled in the art. Among such materials there may be mentioned: antifoams, insect repellents, shading or hueing dyes, anti-viral agents, pH buffering agents, perfume carriers, hydrotropes, anti-redeposition agents, soil-release agents, polyelectrolytes, anti-shrinking agents, anti-wrinkle agents, anti-oxidants, dyes, colorants, sunscreens, anti-corrosion agents, drape imparting agents, anti-static agents, sequestrants and ironing aids. The products of the invention may contain pearlisers and/or opacifiers. A preferred sequestrant is HEDP, an abbreviation for Etidronic acid or 1 -hydroxyethane 1,1-diphosphonic acid.

The compositions are non-aqueous, however some water may be present. Preferably less than 20 wt.% water, more preferably less than 10 wt. % water and most preferably, less than 5 wt. % water by weight of the composition.

Use of the compositions

The compositions described herein are preferably used in the rinse stage of the laundry process. They may be used in their concentrated form and dosed into the laundry process. The composition may be dosed into the laundry process using a measuring cap, a pipet, a dropper or any other suitable dosing means. Preferably the composition is dosed into the rinse stage of the laundry process.

Preferably the concentrated compositions described herein may be used in unit dose capsules or in a dilute at home product. If used in a unit dose capsule, the composition described herein may be packaged as a unit dose in polymeric film soluble in water. Preferably 2 to 15 ml are enclosed in a polymeric film.

If used in a dilute at home product, this means that the composition is sold to the consumer in a concentrated format (as described herein) and the consumer dilutes the product at home. The dilution is with water. For example, the consumer may pour the concentrated product (as described herein) into a container of water to make a more diluted product. Dilution occurs before the laundry process, in other word before the product is dosed into the washing machine or container in which the consumer is doing their laundry. Dilution allows the consumer to follow their regular dosing habits. If the composition is used in a dilute at home product, preferably the consumer is instructed to dilute using a dilution ratio of non-aqueous concentrated liquid fabric conditioner composition to water of 1:2 to 1:20, more preferably 1:3 to 1:12. The consumer may preferably be instructed the shake before use. This is particularly preferred if perfume microcapsules are present in the composition.

Diluting with water prior to being added to the laundry process means that before adding the product to the washing machine or the vessel used for hand washing, i.e. the consumer dilutes the product and then adds it to the drum or drawer of a washing machine of the vessel used for hand washing.

In one aspect of the present invention is provided a method of preserving a fabric conditioner, in particular preventing Aspergillus brasiliensis var niger growth in a fabric conditioner formulation wherein a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids is added to the concentrated fabric conditioner.

In another aspect of the present invention is the use of a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids to preserve a concentrated fabric conditioner as described herein. Examples

Example 1 :

The compatibility of various preservatives in a concentrated fabric conditioner composition was tested.

Table 1: Concentrated fabric conditioner composition

Fabric softening active¹ - TEA quaternary ammonium compound

Preservative² - see table 2

The compositions were prepared by mixing the ingredients in a beaker, then heating to ~ 65°C for 10 minutes with stirring. The compositions were left for a day then a visual assessment was then made of the compositions.

Table 2: Results

Many common preservatives are incompatible with concentrated fabric conditioner compositions. Example 2:

The synergy between aromatic alcohol and carboxylic acid was assessed.

Table 3: Concentrated fabric conditioner composition

Fabric softening active¹ - TEA quaternary ammonium compound

Preservative³ - see table 4

The compositions were prepared by mixing the ingredients in a beaker, then heating to ~ 65°C for 10 minutes with stirring.

Testing for the log reduction of Aspergillus brasiliensis varniger(a fungal species) was carried out as follows:

1. The fungus, Aspergillus brasiliensis var niger was grown on agar with media or food for the fungus.

2. When there was confluent growth with well sporulated subculture on the agar, the spores were extracted by adding between 1 and 5 ml of sterile 0.05% polysorbate 80.

3. The ‘stock’ spore suspension was transferred to a sterile container.

4. After some more processing of the spore suspension, it was diluted with saline to obtain the target concentration of micro-organisms.

5. The product samples were inoculated with yeast suspension or mould spore suspension to give final concentration of 10⁵ CFU/g of product.

6. The inoculated product was stored at 25 +/-1oC.

7. After the defined incubation period 2 days was completed, an aliquot of the product was taken out and the number of residual spores (ultimately measured as mould colonies) in the inoculated product was measured.

8. This was done by plating the aliquot on a food I media with agar suitable for growth of mould or fungi like Sabouraud Dextrose Agar as the plating media. 9. The aliquot was first diluted to obtain a countable number on the agar plates.

10. The results were recorded and reported in log numbers. Table 4: Results

In Table 4 the total preservative composition was maintained at 0.8 wt.%. Table 4 demonstrates that a preservative composition comprising two ingredients selected from aromatic alcohols and/or carboxylic acids provides improved preservation compared to the two ingredients alone.

Claims

1. A concentrated fabric conditioner formulation comprising: a) 10 wt.% to 85 wt.% cationic fabric softening active; b) 0.01 to 5 wt.% Preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids; and c) less than 20 wt.% water.

2. A concentrated fabric conditioner composition according to any proceeding claim, wherein the preservative composition comprises at least a carboxylic acid and an aromatic alcohol.

3. A concentrated fabric conditioner composition according to any proceeding claim, wherein the preservative composition comprises lactic acid.

4. A concentrated fabric conditioner according to any preceding claim, wherein the composition comprises organic solvent.

5. A concentrated fabric conditioner according to claim 4, wherein the organic solvent comprises solvents selected form hydrocarbons and/or aromatic alcohols.

6. A unit dose product comprising the concentrated fabric conditioner composition according to claims 1 to 5 enclosed in a polymeric film.

7. A method of using the concentrated fabric conditioner according to claims 1 to 5, wherein the concentrated fabric conditioner is diluted with water prior to addition to the laundry process.

8. A method of preserving a concentrated fabric conditioner wherein a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids is added to the concentrated fabric conditioner.

9. A method according to claim 8 wherein the method of preserving is a method of preventing Aspergillus brasiliensis growth in a fabric conditioner formulation. A use of a preservative composition comprising at least two ingredients selected from aromatic alcohols and/or carboxylic acids to preserve a concentrated fabric conditioner comprising 10 wt.% to 85 wt.% cationic fabric softening active and less than 20 wt.% water.