WO2002003926A2

WO2002003926A2 - Fabric conditioning composition

Info

Publication number: WO2002003926A2
Application number: PCT/EP2001/006956
Authority: WO
Inventors: Stuart Bernard Fraser
Original assignee: Unilever Plc; Unilever Nv; Hindustan Lever Limited
Priority date: 2000-07-10
Filing date: 2001-06-19
Publication date: 2002-01-17
Also published as: BR0112343A; GB0016847D0; AR028793A1; CA2412895A1; WO2002003926A3; AU2001285763A1; EP1299515A2

Abstract

A plastics package and a household treatment composition therein in which the composition comprises an oil having a ClogP equal to or greater than 3.0 and a perfume with at least 50 % by number of the perfume components having a ClogP equal to or greater than 2.5. A method of reducing or preventing the loss of one or more perfume ingredients from a household treatment composition into and/or through a plastics container comprises adding the oily ingredient so as to solubilise perfume ingredients having a ClogP of 2.5 or more.

Description

Fabric Conditioning Composition

Technical Field

The present invention relates to packages comprising a plastics container and a household treatment composition therein. It also relates to a method of reducing and/or preventing loss of perfume from a household treatment composition upon storage of the composition.

Background and Prior Art

Household products such as laundry and personal care products are conventionally fragranced to deliver a more pleasing aroma to consumers when used.

Perfumes used in the household care industry traditionally contain a wide variety of ingredients, often more than 10, e.g. more than 20. These ingredients can range from very hydrophobic to very hydrophilic ingredients.

A problem with providing perfumed household compositions is to ensure compatibility of as many of the ingredients of the perfume with the other ingredients in the compositions. For instance, aqueous laundry compositions, such as aqueous rinse conditioners contain aqueous solvents which will generally be compatible with the more hydrophilic components of a perfume but not with more hydrophobic ingredients, with the result that the hydrophobic perfume ingredients will not disperse or dissolve in the composition. Such ingredients thus have a tendency to volatilize at an undesirably early stage, i.e. before the consumer desires that the perfume is released.

A way of addressing the problem has been to increase the dosage of the perfume so as to provide significant perfume aroma even when there is early loss of certain perfume ingredients. However, this is not a desirable solution to the above-mentioned problem since high levels of perfume can adversely affect the stability (e.g. viscostability) of household products, and perfume is generally one of the more expensive ingredients in a household treatment composition.

A further way of addressing the problem of undesired early release of perfume ingredients is by including in the packaging, which contains the composition, a barrier layer (essentially blocking ingredients from leaking through the package) . For instance in EP 0918705 (Colgate-Palmolive) , there is disclosed a pouch package for containing household treatment liquids. The pouch has a multilayer structure, at least one layer of which is a barrier layer.

However, in mass market products, it is undesirable to provide additional layers in the packaging as this can increase productions costs of the package unacceptably, for instance, raw material costs rise, production time increases and more complicated, expensive machinery capable of incorporating the barrier layer may be required. It can also be less environmentally compatible, e.g. less biodegradable. Therefore it is desirable to operate with packaging which is as simple as possible. Traditionally single or bilayer thermoplastics containers are used for the storage and delivery of fragranced household and personal care products. However, these suffer from the problem identified above. That is the loss of fragrance, especially hydrophobic components, from compositions at an undesirable (early) stage, e.g. during storage.

Although not fully understood, it is believed that loss of fragrance is due to two mechanisms, namely permeation of perfume ingredients through the package and absorption of the perfume ingredients into the package.

For products contained within plastics bottles, absorption is the significant problem.

Accordingly, it is desirable to provide a household composition which prevents undesirable loss of perfume during storage. It is particularly desirable to prevent undesirable early loss of hydrophobic perfume ingredients which are prone to volatalise at an early stage when present in household treatment compositions which are typically aqueous.

It is also preferably desirable to provide a composition, such as a fabric conditioning composition, which improves perfume deposition on fabrics and reduces perfume loss during drying, e.g. during the drying cycle of a tumble dryer. Object of the invention

The present invention seeks to address one or more of the problems and to provide one or more of the benefits identified above.

Surprisingly, we have now found that a household treatment composition comprising an oil wherein the hydrophobicity of the oil is compatible with that of at least one of the perfume ingredients, exhibits reduced loss of hydrophobic perfume ingredients from the composition into and/or through the surrounding package.

We have also found that such oil-based compositions provide improved perfume delivery to fabric and better perfume longevity upon drying.

Summary of the Invention

According to the present invention there is provided a plastics package and a household treatment composition therein, the composition comprising an oil having a ClogP equal to or greater than 3.0 and a perfume with at least 50% by number of the perfume components having a ClogP equal to or greater than 2.5.

According to the invention, there is also provided, a method of reducing and/or preventing the loss of one or more perfume ingredients from a household treatment composition into and/or through a plastics container comprising adding an oily ingredient having a ClogP of 3.0 or more into the composition so as to solubilise perfume ingredients having a ClogP of 2.5 or more.

Detailed Description of the invention

The present invention relates to household treatment compositions, especially laundry and/or personal care compositions. It is particularly envisaged that the compositions are fabric conditioning compositions, e.g. fabric softening compositions.

It is preferred that the household treatment compositions are aqueous .

The following ingredients are present in the household compositions used in the invention:

Oil

The compositions of the present invention comprise at least one oil or oily ingredient. The oil may be a mineral oil, an ester oil and/or natural oils such as vegetable oils. However, ester oils or mineral oils are preferred. The oil may also be a silicone oil although it is preferred that the oil is not a silicone oil.

The oil has a ClogP of equal to or greater than 3.0, more equal to or greater than 4.0, most preferably greater than 5.0, e.g. greater than 6.0. The method of measuring ClogP is as defined below. Of course, the oil may comprise a mixture of different ingredients, e.g. a mineral oil can be a mixture of different alkyl chain length compounds. In this case, a ClogP equal to or greater than 3.0 denotes that the number average ClogP of all the oil ingredients is 3.0 is more.

Suitable ester oils include fatty esters of mono or polyhydric alcohols having from 1 to 24 carbon atoms in the hydrocarbon chain, and mono or polycarboxylic acids having from 1 to 24 carbon atoms in the hydrocarbon chain, provided that the total number of carbon atoms in the ester oil is equal to or greater than 16, and that at least one of the hydrocarbon chains has 12 or more carbon atoms.

Suitable ester oils include sugar ester oils, such as those disclosed in WO 98/16538 (UNILEVER) . Other ester oils include saturated ester oils, such as the PRIOLUBES (ex. ϋniqema) . 2-ethyl hexyl stearate (PRIOLUBE 1545) , neopentyl glycol monomerate (PRIOLUBE 2045) and methyl laurate (PRIOLUBE 1415) are particularly preferred although oleic monoglyceride (PRIOLUBE 1407) and neopentyl glycol dioleate (PRIOLUBE 1446) are also suitable.

It is preferred that the viscosity of the ester oil is from 0.002 to 0.4 Pa.S (2 to 400 cps) at a temperature of 25°C at

-₁ 106s , measured using a Haake rotoviscometer, and that the density of the mineral oil is from 0.8 to 0.9g.cm at 25 C. Suitable mineral oils include branched or straight chain hydrocarbons (e.g. paraffins) having 8 to 35, more preferably 9 to 20 carbon atoms in the hydrocarbon chain.

Preferred mineral oils include the Marcol technical range of oils (ex Esso) although particularly preferred is the Sirius range (ex Silkolene) or Semtol (ex. Witco Corp.). The molecular weight of the mineral oil is typically within the range 100 to 400.

One or more oils of any of the above mentioned types may be used.

In addition to preventing perfume migrating into and through packaging, it is believed that the oil provides excellent perfume delivery to the cloth and also increases perfume longevity upon storage of the composition.

The oil may be present in an amount from 0.5-15% by weight, more preferably 0.6-9% by weight, most preferably 0.7-8%, e.g. 0.9-7% or even 1.0 to 4.5% by weight based on the total weight of the composition.

The oil referred to herein, is preferably added to the composition as a separate component, that is, in addition to any oil which may be present in other components of the composition.

Perfume At least 50% by number of the perfume components, more preferably 60%, most preferably 70%, e.g. 85% should have a ClogP value equal to or greater than 2.5, more preferably equal to or greater than 3.0, even more preferably equal to or greater than 4.0, most preferably equal to or greater than 5.0, e.g. greater than 6.0 or even 7.0.

Suitable perfumes include those disclosed in "Perfume and Flavor Chemicals (Aroma Chemicals)", by Steffen Arctander, published by the author in 1969, the contents of which are incorporated herein by reference.

The perfume is preferably present in the composition in an amount of 0.01 to 15%, more preferably 0.05 to 12%, most preferably 0.07 to 11% by weight, based on the total weight of the composition.

Without wishing to be bound by theory, it is believed that at least some of the perfume partitions into the oil phase so that absorption into plastic packaging is reduced.

The perfume and oil preferably have a high proportion of their ingredients with similar ClogP values as this enables the perfume to partition into the oil more effectively.

Accordingly, the perfume must be compatible with the oil. In the context of the present invention, the term "compatible" means that the perfume and oil have similar hydrophobicities as defined by ClogP. Preferably, the weight ratio of oil to perfume is in the range 50:1 to 1:1, more preferably 40:1 to 2:1, most preferably 35:1 to 3:1, e.g. 20:1 to 4:1 or even 15:1 to 5:1.

A parameter which can be used to define compounds of suitable hydrophobicity is the octanol water partition coefficient, frequently abbreviated to ClogP. In the present invention, ClogP is calculated according to ClogP p.c. program version 3.06, available from Daylight Chemical Information Systems. Using this parameter it is possible to define a minimum level of hydrophobicity which corresponds with efficient retention of the perfume in the oil phase of the composition.

Household Treatment Compositions

Compositions suitable for use in the present invention include household treatment compositions such as hard surface cleaners, personal care compositions and laundry compositions, such as detergent cleaning compositions. The invention is particularly suitable for use with fabric softening compositions, especially aqueous fabric softening compositions where perfume loss and instability of compositions when perfume is added is a serious problem.

Fabric Softening Compositions

Typical ingredients which can be present in fabric softening compositions include: Fabric Softening Agent

Any suitable fabric softening compound is suitable for use with the present invention, in particular nonionic softening compounds and cationic softening compounds .

It is preferred if the fabric softening compound is cationic in nature. Preferably the cationic fabric softening compound of the invention has two long chain alkyl or alkenyl chains with an average chain length greater than

C₁₂, more preferably each chain has an average chain length greater than C±Q , more preferably at least 50% of each long chain alkyl or alkenyl group has a chain length of Cis-

It is preferred if the long chain alkyl or alkenyl groups of the fabric softening compound are predominantly linear.

The cationic fabric softening compositions of the invention are compounds molecules which provide excellent softening, characterised by chain melting -Lβ to Lα - transition temperature greater than 25 C, preferably greater than 35 C, most preferably greater than 45 C. This Lβ to Lα transition can be measured by DSC as defined in "Handbook of Lipid Bilayers, D Marsh, CRC Press, Boca Raton Florida, 1990 (Pages 137 and 337) .

It is especially preferred if the fabric softening compound is a quaternary ammonium material which comprises a compound having two C₁₂-₁₈ alkyl or alkenyl groups connected to the molecule via at least one an ester link. It is more preferred if the quaternary ammonium material has two ester links present. An especially preferred ester-linked quaternary ammonium material for use in the invention can be represented by formula (I) :

R

R- -N ^•(CH₂)n—T—R X (I)

wherein each R group is independently selected from C₁-₄ alkyl, hydroxyalkyl or C₂-₄ alkenyl groups; and wherein each

2

R group is independently selected from Cs-₂₈ alkyl or alkenyl groups;

0 0

T is —0—C— or —C—0—; X is any suitable anion and

n is 0 or an integer from 1-5.

A second preferred type of quaternary ammonium material can be represented by formula (II) : TR

(Rl ) 3— N — (CH₂ ) : -CH X ( ID

( CH₂ ) _mTR₂

wherein Ri, R₂, X n and T are as defined above and m is an integer from 1 to 5.

Suitable compounds within this class include triethanolamine based quaternary ammonium surfactants.

It is advantageous for environmental reasons if the quaternary ammonium material is biologically degradable.

Preferred materials of this class such as 1,2 bis [hardened tallowoyloxy] -3- trimethylam onium propane chloride and their method of preparation are, for example, described in US 4 137 180 (Lever Brothers) . Preferably these materials comprise small amounts of the corresponding monoester as described in US 4 137 180 for example 1-hardened tallowoyloxy -2-hydroxy trimethylammonium propane chloride.

The fabric softening agent may also be polyol ester quats (PEQs) as described in EP 0638 639 (Akzo) .

A further type of quaternary ammonium material is represented by formula (III) : R3

R_l— N — R₂ X Formula (III)

R₄

where Ri and R₂ are Cs-₂₈ alkyl or alkenyl groups; R₃ and R₄ are Cι_₄ alkyl or C₂-₄ alkenyl groups and X is as defined above .

Examples of compounds within this formula include di (tallow alkyl) dimethyl ammonium chloride, di (tallow alkyl) dimethyl ammonium methyl sulphate, dihexadecyl dimethyl ammonium chloride, di (hardened tallow alkyl) dimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride and di (coconut alkyl) dimethyl ammonium chloride.

For cationic surfactants of formulae (I) , (II) or (III) , the total average iodine value of the parent fatty acid from which R]_ to R₄ inclusive are formed is from 0 to 20, more preferably from 0 to 10, most preferably from 0 to 5, e.g. 0 to 2.

The ratio of water- insoluble oil to fabric softening compound is preferably 1:10 to 10:1, more preferably 1:5 to 5:1, most preferably 1:3 to 3:1.

Preferably the level of quaternary ammonium compound is at least 1% by weight of the composition, more preferably less than 20% by weight of the composition; especially interesting are dilute compositions which comprise between 1 and 7 % by weight of quaternary ammonium compound because absorption into plastic is particularly severe for dilute formulations since these have more plastic packaging relative to the active ingredients than concentrates.

Preferably, the weight ratio of cationic softener to oil in the composition is in the range 5:1 to 1:10, more preferably 4:1 to 1:5, most preferably 3:1 to 1:3.

Water

The compositions of the invention are preferably aqueous based.

Typically, the level of water present is from 1-99% by weight, more preferably 20-98% by weight, even more preferably 40-97% by weight, most preferably 60-96% by weight, based on the total weight of the composition.

Electrolytes

The composition may comprise one or more inorganic or organic electrolytes. Suitable electrolytes include calcium chloride and citric acid. Co-active Softening Surfactants

Co-active softening surfactants for the cationic surfactant may also be incorporated in an amount from 0.01 to 20% by weight, more preferably 0.05 to 10%, based on the total weight of the composition. Preferred co-active softening surfactants are fatty acids, fatty amines and fatty N- oxides.

Other Optional Ingredients

The compositions may also contain one or more optional ingredients conventionally included in fabric conditioning compositions such as pH buffering agents, fluorescers, colourants, hydrotropes, antifoaming agents, antiredeposition agents, polyelectrolytes, enzymes, optical brightening agents, anti-shrinking agents, anti-wrinkle agents, anti-spotting agents, germicides, fungicides, anti- corrosion agents, drape imparting agents, anti-static agents, ironing aids and dyes.

Product Form

The compositions may be aqueous dispersions, macro-emulsions or micro-emulsions. It has been found that the invention works particularly well with compositions based on emulsions, especially aqueous emulsions. Accordingly, it is especially preferred that the composition is an emulsion. Method of production

The compositions may be prepared according to any suitable method. The following 2 methods are merely examples:

In a first method, antifoam, preservative and dyestuff were dissolved in warm water followed by addition of electrolyte to form an aqueous solution. The cationic fabric softening agent, tallow fatty acid, oil and any co-actives e.g. nonionic surfactants were mixed in the appropriate ratios and co-melted under heat. This premix was added to the aqueous solution over 5 minutes with stirring. The resulting mixture was be circulated through a Janke and Kunkel mill set at maximum shear (10,000 rpm) . Finally, perfume was stirred directly into the mix.

In a second method, the first method is followed but, instead of stirring the perfume directly into the mix, it was premixed with the oil and then added into the mixture under gentle heating.

Thermoplastics Package

^' The invention relates to a package comprising a plastics container containing a liquid composition. Preferably the . package is a conventional container such as a theromplastic bottle or pouch for laundry or personal care products.

Suitable thermoplastics include polar and non-polar thermoplastics.

Preferred non-polar thermoplastics include polyolefin resins, for example polymers derived from one or more aliphatic or aromatic alkylenes, e.g. polymers containing units derived from at least one of ethylene, propylene, butylene, styrene, hexene and octene. Other suitable non- polar resins may comprise a compound of one or more polymers of polyethylene, polypropylene, ethylene/propylene copolymers or ethylene/propylene/butylene terpolymers.

Polyethylene resins can be low density polyethylene, linear low density polyethylene (density of from 0.910 to 0.925 g

-₃ cm ) , medium density polyethylene, linear medium density

-₃ polyethylene (density of from 0.925 to 0.950g cm ), high

-₃ density polyethylene (density of from 0.950 to 0.980g cm ), or a combination of high density polyethylene and linear low density polyethylene.

Other thermoplastic materials which may be included in plastics containers for use in the present invention include polyethylene teraphthalate and polyvinyl chloride. It is especially preferred that the thermoplastic material is high density polyethylene as it has been found that the compositions of the invention deliver significantly improved perfume retention with such thermoplastic packages.

Examples

The invention will now be illustrated by the following non- limiting examples. Further will be apparent to the person skilled in the art.

Compositions according to the invention are denoted by a number whilst comparative compositions are denoted by a letter.

Example 1

In the following example, samples of various compositions were stored in either glass vials or high density polyethylene plastics bottles for 28 days at 45 C. The high density polyethylene used had a density between 0.95 to

-₃ 0.962g cm (available from Alpla) .

The following compositions were prepared according to the first method described above.

Table 1

All values are in % by weight of the overall composition.

DHTDMAC is dihardened tallow dimethyl ammonium chloride (available as Arquad 2HT ex Akzo) .

Semtol 70/50 is a C₂₀ hydrocarbon oil.

The perfume is Soft-Touch 178 (ex Givaudan Roure) .

Samples of compositions A and 1 were stored in glass vials at ambient and at 45 C for 4 weeks. These were the "reference samples".

Further samples of compositions A and 1 were stored in high density polyethylene bottles at 45 C for 4 weeks.

After 4 weeks, the 6 samples were analysed by headspace gas chromatography.

Table 2 below gives the ratios of the headspace concentrations measured above aliquots taken from the samples stored in plastic bottles at 45 C relative to the headspace concentration measured above aliquots of the reference samples stored in vials at 45 C.

That is, ratios A and 1 represent Composition A (stored in plastic) : composition A (stored in glass) and composition 1

(stored in plastic) : composition 1 (stored in glass) respectively.

The results are given as Gas Chromatographic (GC) Retention times in minutes.

GC analysis showed no difference in headspace concentration between the ambient glass stored samples and the samples o stored in glass at 45 C. Thus, any effect shown was not attributable to the increased temperature.

Table 2

The results in table 2 demonstrate that the reduction in headspace for the compositions of the invention are significantly smaller than those for comparative example A. Thus, a much greater proportion of the perfume is retained in composition 1 than in composition A.

Example 2

The following compositions were prepared by mixing the surfactant, water and, if present, oil and nonionic surfactant and heating to 45°C with stirring. The perfume was added slowly and the mixture stirred mixed for 1 hour.

In all of compositions B, C, 2 and 3, the perfume comprised a 1:1:1:1 weight ratio mixture of benzyl alcohol, florhydral (tradename) , hexyl salicilate and hexyl cinnamic aldehyde. The perfume was prepared by stirring the ingredients together at ambient temperature until a homogeneous mixture was formed.

Composition B comprised an aqueous dispersion of 3.9% by weight of DHTDMAC and 0.35% by weight of perfume.

Composition 2 comprised an aqueous emulsion of 2.2% by weight DHTDMAC, 3.3% by weight of Semtol 70/20 (an oil having a ClogP og greater than 3.0), 0.1% by weight glycerol monostearate and 0.35% by weight perfume.

Composition C comprised an aqueous dispersion of 13% by weight 1, 2-ditallowyloxyethyl-3-ammoniopropane chloride (ex Clariant) , 2.15% IPA and 0.95% by weight perfume.

Composition 3 comprised an aqueous emulsion of 9.75% by weight l,2-ditallowyloxyethyl-3-ammoniopropane chloride, 3.25% by weight sucrose tetraerucate ex Mitsubishi KK (an oily sugar-based mixture comprising an oil having a ClogP greater than 3.0), 0.6% by weight Genapol C200 (ex Clariant) and 0.95% by weight perfume.

Each composition was stored in glass for 24 hours at ambient temperature then aliquots were weighed into the various containers, E-I, where, in the column headed "container type" in table 3 below, letters "E", "F", "G", "H" and "I" have the following meaning:

E: 500ml high density polyethylene container

F: 500ml polyethylene terephthalate container

G: 1000ml polypropylene container

H: 1000ml high density polyethylene container I: glass container

Table 3

Weight "W" denotes the weight of the container (grams) excluding its closure.

Weight "W+S" denotes the weight (grams) of W plus the weight of the composition, the relevant composition selected from B, C, 2 or 3 being shown in brackets after the weight.

Test method

All of the products were stored at 37°C, except products 6, 12, 18 and 24 which were stored at ambient temperature. After 3 months storage, aliquots were taken for analysis by HPLC.

Approximately 0.4g of the concentrated compositions (i.e. any product containing compositions C or 3) and approximately l.Og of the dilute products (i.e. any product containing compositions B or 2) were weighed accurately into headspace vials and 10ml of ethanol added.

Compositions were analysed for loss of perfume by reversed phase HPLC on a HP 1100 system using an octyl silica column, with water and acetonitrile as eluents and photodiode array detection. Chromatograms were quantified using external standards which gave linear responses .for the components of the perfume mixture.

The results below are expressed as the percentage of perfume remaining in the plastics container. This was calculated as follows:

The amount of perfume lost from the compositions stored in the glass container at 37°C was compared to the amount lost from the compositions stored in the glass container at ambient temperature. The difference in grams, (R) , represented the expected amount of perfume that would be lost through evaporation alone due to high temperature storage of the composition. It is assumed that no perfume is lost into or through the glass container.

The amount of perfume remaining in compositions stored in plastics containers was then calculated. The results were adjusted by amount (R) to give the amount of perfume lost into and/or through the plastics container. This was compared to the amount of perfume present initially and, from this, the percentage of perfume remaining in the composition after 3 months storage was calculated. Thus, in the following table, 100% denotes that, accounting for perfume loss through evaporation, all the perfume remains after 3 months and 0% denotes that all the perfume has leaked into and/or through the container.

This calculation was made for each of the 4 components of the perfume.

The results are given in table 4

Table 4

The results demonstrate that for compositions where no oil having a ClogP equal to or greater than 3.0 is present (products 19, 21 and 22), the loss of hydrophobic perfume ingredients is very severe but when the oil is present (see products 7 to 16) , there is a dramatic improvement in retention of such components.

This table also demonstrates that the invention is particularly beneficial where the composition is in the form of an emulsion.

Claims

Claims :

1. A plastics package and a household treatment composition therein, the composition comprising an oil having a ClogP equal to or greater than 3.0 and a perfume with at least 50% by number of the perfume components having a ClogP equal to or greater than 2.5.

2. A package and composition as claimed in claim 1 wherein the package comprises a high density polyethylene layer.

3. A package and composition as claimed in either claim 1 or claim 2 wherein the composition comprises a fabric softening compound.

4. A package and composition as claimed in any one of the preceding claims wherein fabric softening compound is present in an amount of from 1 to 7% by weight based on the total weight of the composition.

5. A package and composition as claimed in any one of the previous claims wherein the oil has a ClogP of equal to or greater than 4.0.

6. A package and composition as claimed in any one of the previous claims wherein at least 50% by number of the perfume ingredients have a ClogP of equal to or greater than 4.0.

7. A package and composition as claimed in any one of the preceding claims wherein the oil is present in an amount of from 0.9 to 7% by weight based on the total weight of the composition.

8. A package and composition as claimed in any one of the preceding claims wherein the weight ratio of oil to ^• perfume is in the range from 35:1 to 3:1.

9. A package and composition as claimed in any one of the preceding claims wherein the composition is in the form of an emulsion.

10. A method of reducing and/or preventing the loss of one or more perfume ingredients from a household treatment composition into and/or through a plastics container comprising adding an oily ingredient having a ClogP of 3.0, or more into the composition so as to solubilise perfume ingredients having a ClogP of 2.5 or more.