EP0332270B2

EP0332270B2 - Fabric conditioning composition

Info

Publication number: EP0332270B2
Application number: EP89200545A
Authority: EP
Inventors: John Robert Martin; William Frederick Soutar Neillie; Graham Andrew Turner; Douglas Wraige
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 1988-03-11
Filing date: 1989-03-06
Publication date: 2001-07-04
Anticipated expiration: 2009-03-06
Also published as: EP0332270A3; AU620082B2; ES2087861T3; JPH026662A; GB8805837D0; EP0332270A2; DE68926584T3; CA1341483C; DE68926584D1; JP2551479B2; BR8901135A; ES2087861T5; AU3124389A; DE68926584T2; ZA891845B; EP0332270B1

Description

This invention relates to a fabric conditioning composition suitable for conditioning fabrics during the rinse step of a fabric laundry process.
It is known to treat fabrics with a fabric conditioning composition following a fabric washing process which often involves the use of anionic surface active materials.
In the treatment of fabrics in the rinse cycle of a fabric laundry process it is known in the art to add one or more conditioning agents. For instance it is known from British Patent Specification GB-A-1 260 584 (ARMOUR) to soften fabrics in the rinse cycle by the use of a composition containing a quaternary ammonium compound and a tertiary amine oxide.
It is known that anionic surface active materials carried over from the wash cycle of the fabric laundry process can have a detrimental effect on the effectiveness of fabric conditioning compositions containing fabric softening agents which are used in the rinse step of the fabric laundry process. This problem can be alleviated if the fabrics are thoroughly rinsed before they are treated with a fabric conditioner, alternatively this problem can possibly be overcome by using fabric conditioning compositions which are not as sensitive to the presence of anionic surface active agents. Furthermore, it is known from European patent 63 899 (UNILEVER), to overcome the problem of anionic carry-over by the use of anionic scavengers, such as aluminium chlorohydrate.
EP-A-0,210,704 discloses a water-insoluble, water-dispersible fabric softening composition comprising an amine, a phosphate ester and an amine oxide. The softening composition is intended for use with detergents, to provide a softening-through-the-wash effect.
GB-A-2,160,886 discloses a solid detergent bar which is also capable of softening fabrics during washing. The bar comprises an anionic, nonanionic, amphoteric, cationic or zwitterionic surfactant; a builder; a long chain aliphatic amide or amine oxide; a cellulosic derivative; a softening agent and talc, aluminium formate or calcined sodium carbonate. The softening agent may be a quaternary ammonium salt having at least one C₁₆-C₂₂ aliphatic radical, an imidazolinium salt, a tertiary amine or a smectic clay. The combination of an amine and a quaternary ammonium softening agent is not, however, specifically disclosed.
FR-A-2,593,517 describes a detergent composition which is also capable of softening fabrics. The composition includes, inter alia, an anionic surfactant; a cationic softener, which may be a di-lower-di-higher alkyl quaternary ammonium compound; and an ethoxylated tertiary amine.
It is an object of the present invention to provide fabric conditioning compositions which provide improved softening benefits to fabrics, in the absence, but also in the presence of anionic carry-over.
It is a further object of the present invention to provide fabric conditioning compositions which are stable, easy to prepare especially when manufacturing a product with a viscosity above 100 mPas, and which have an attractive creamy appearance.
We have now surprisingly discovered that one or more of the above mentioned objects can be fulfilled if in the fabric conditioning composition a cationic fabric softening agent is combined with certain other components.
Thus, accordingly there is provided an aqueous liquid fabric conditioning composition comprising from 1 to 60% by weight of a combination of:
(i) 20% to 90% by weight of a cationic quaternary ammonium fabric softening agent having two C_12-24 hydrocarbyl chains and a solubility in water at pH 2.5 and 20°C of less than 10g/l;
(ii) 5% to 70% by weight of an amine; and
(iii) 5% to 60% by weight of an amphoteric fabric conditioning material wherein said amphoteric fabric conditioning material is selected from tertiary amine oxides of the following formula:
wherein:
a) R₂₅ and R₂₆ are C_8-24 hydrocarbyl chains, R₂₇ is an hydrocarbylgroup containing 1-4 carbon atoms or a group -(CH₂,CH₂O)_nH wherein n is as integer from 1 to 6;

Detailed description of the invention

Fabric conditioning compositions according to the present invention comprise at least the following three active ingredients:
(i) a cationic tabric softening agent
(ii) an amine
(iii) an amphoteric fabric conditioning material

The cationic fabric softening agent

The cationic fabric softener material is a cationic material which is water-insoluble in that these materials have a solubility in water at pH 2.5 and 20°C of less than 10 g/l. The materials are cationic quaternary ammonium salts having two C12-24 hydrocarbyl chains.
Well-known species of substantially water-insoluble quaternary ammonium compounds have the formula
wherein R₁ and R₂ represent hydrocarbyl groups trom about 12 to about 24 carbon atoms; R₃ and R₄ represent hydrocarbyl groups containing from 1 to about 4 carbon atoms; and X is an anion, preferably selected from halide, methyl sulfate and ethyl sulfate radicals.
Representative examples of these quaternary softeners include ditallow dimethyl ammonium chloride; ditallow dimethyl ammonium methyl sulfate; dihexadecyl dimethyl ammonium chloride; di(hydrogenated tallow) dimethyl ammonium methyl sulfate; dihexadecyl diethyl ammonium chloride; di(coconut) dimethyl ammonium chloride. Ditallow dimethyl ammonium chloride, di(hydrogenated tallow) dimethyl ammonium chloride, di(coconut) dimethyl ammonium chloride and di(coconut) dimethyl ammonium methosulfate are preferred.
Suitable materials also include dialkyl ethoxyl methyl ammonium methosulphate based on soft fatty acid, dialkyl ethoxyl methyl ammonium methosulphate based on hard fatty acid, and a material in which R₃ and R₄ represent methyl, R₁ is C_13-15, R₂ is CH₂CH₂OCOR, where R is stearyl, and X is methosulphate. Materials in which R₂, R₃ and R₄ each represent methyl, R₁ is the group
where R is hardened tallow and X is methosulphate are also suitable. Ditallow dimethyl ammonium chloride, di(hydrogenated tallow alkyl) dimethyl ammonium chloride, di(coconut alkyl) dimethyl ammonium chloride and di(coconut alkyl) dimethyl ammonium methosulfate are preferred.
Other preferred cationic compounds include those materials as disclosed in EP 239,910 (P&G).
In this specification the expression hydrocarbyl group refers to alkyl or alkenyl groups optionally substituted or interrupted by functional groups such as -OH, -O-, -CONH-, -COO-, etc.
Other preferred materials are the materials of formula
R₅ being partially hardened tallow, which is available from Stepan under the tradename Stepantex VRH 90 and
where R₈, R₉ and R₁₀ are each alkyl or hydroxyalkyl groups containing from 1 to 4 carbon atoms, or a benzyl group. R₆ and R₇ are each an alkyl or alkenyl chain containing from 11 to 23 carbon atoms, and X^- is a water soluble anion, substantially free of the corresponding monoester.
Another class of preferred water-insoluble cationic materials are selected from the hydrocarbylimidazolinium salts believed to have the formula:
wherein R₁₃ is a hydrocarbyl group containing from 1 to 4, preferably 1 or 2 carbon atoms, R₁₁ is a hydrocarbyl group containing from 12 to 24 carbon atoms, R₁₄ is an hydrocarbyl group containing from 12 to 24 carbon atoms and R₁₂ is hydrogen or an hydrocarbyl containing from 1 to 4 carbon atoms and A^- is an anion, preferably a halide, methosulfate or ethosulfate.
Preferred imidazolinium salts include 1-methyl-1-(tallowylamido-) ethyl -2-tallowyl- 4,5-dihydro imidazolinium methosulfate and 1-methyl-1-(palmitoylamido)ethyl -2-octadecyl-4,5- dihydroimidazolinium chloride. Other useful imidazolinium materials are 2-heptadecyl-1-methyl-1-(2-stearylamido)ethyl-imidazolinium chloride and 2-lauryl-1-hydroxyethyl-1-oleyl-imidazolinium chloride. Also suitable herein are the imidazolinium fabric softening components of US patent No 4 127 489, incorporated by reference.
Representative commercially available materials of the above classes are the quaternary ammonium compounds Arquad 2HT (ex AKZO); Noramium M2SH (ex CEKA); Aliquat-2HT (Trade Mark of General Mills Inc), Stepantex Q185 (ex Stepan); Stepantex VP85 (ex Stepan); Stepantex VRH90 (ex Stepan); Synprolam FS (ex ICI) and the imidazolinium compounds Varisoft 475 (Trade Mark of Sherex Company, Columbus Ohio) and Rewoquat W7500 (Trade Mark of REWO).

The amines

The compositions according to the invention also contain in addition to cationic fabric softening agents, one or more amines.
The term "amine" as used herein can refer to
(i) amines of formula
wherein R₁₅, R₁₆ and R₁₇ are defined as below;
(ii) amines of formula
wherein R₁₈, R₁₉, R₂₀ and R₂₁, m and n are defined as below.
(iii) imidazolines of formula
wherein R₁₁, R₁₂ and R₁₄ are defined as above.
(iv) condensation products formed from the reaction of fatty acids with a polyamine selected from the group consisting of hydroxy alkylalkylenediamines and dialkylenetriamines and mixtures thereof. Suitable materials are disclosed in European Patent Application 199 382 (Procter and Gamble).
When the amine is of the formula I above, R₁₅ is a C₆ to C₂₄, hydrocarbyl group, R₁₆ is a C₁ to C₂₄ hydrocarbyl group and R₁₇ is a C₁ to C₁₀ hydrocarbyl group. Suitable amines include those materials from which the quaternary ammonium compounds disclosed above are derived, in which R₁₅ is R₁, R₁₆ 6 is R₂ and R₁₇ is R₃. Preferably, the amine is such that both R₁₅ and R₁₆ are C₆-C₂₀ alkyl with C₁₆-C₁₈ being most preferred and with R₁₇ as C_1-3 alkyl, or R₁₅ is an alkyl or alkenyl group with at least 22 carbon atoms and R₁₆ and R₁₂ are C_1-3 alkyl. preferably thee amines are protonated with hydrochloric acid, orthophosphoric acid (OPA), C_1-5 carboxylic acids or any other similar acids, for use in the fabric conditioning compositions of the invention.
When the amine is of formula II above, R₁₈ is a C₆ to C₂₄ hydrocarbyl group, R₁₉ is an alkoxylated group of formula -(CH₂CH₂O)_yH, where y is within the range from 0 to 6, R₂₀ is an alkoxylated group of formula -(CH₂CH₂O)_zH where z is within the range from 0 to 6 and m is an integer within the range from 0 to 6, and is preferably 3. When m is 0, it is preferred that R₁₈ is a C₁₆ to C₂₂ alkyl and that the sum total of z and y is within the range from 1 to 6, more preferably 1 to 3. When m is 1, it is preferred that R₁₈ is a C₁₆ to C₂₂ alkyl and that the sum total of x and y and z is within the range from 3 to 10.
Representative commercially available materials of this class include Ethomeen (ex Armour) and Ethoduomeen (ex Armour).
Preferably the amines of type (ii) or (iii) are also protonated for use in the fabric conditioning compositions of the invention.
When the amine is of type (iv) given above, a particularly preferred material is
where R₂₂ and R₂₃ are divalent alkenyl chains having from 1 to 3 carbons atoms, and R₂₄ is an acyclic aliphatic hydrocarbon chain having from 15 to 21 carbon atoms. A commercially available material of this class is Ceranine HC39 (ex Sandoz).

The tertiary amine oxide fabric conditioning material

The tertiary amine oxide fabric conditioning material for use in a composition according to the invention should be a fabric substantive amphotheric material. Suitable amphoteric materials form a particulate dispersion at a concentration of less than 1 g/l at at least one temperature between 0 and 100°C.
It is already known, for instance from US 3,984,335 (BASF company) to use a fatty amphoteric compound having one long hydrocarbyl chain in liquid fabric softening components.
The tertiary amine oxide compounds have two long hydrocarbyl chains, each chain having 8-24 C-atoms, preferably 10-20 C-atoms, most preferred around 16 C-atoms.
Preferably the amphoteric fabric substantive materials are water insoluble and have a solubility in water at pH 2.5 at 20°C of less than 10 g/l. The HLB of the amphoteric fabric substantive material is preferably less than 10.0.
Examples of amphoteric materials of the above groups and their method of preparation are given in our co-pending European patent application EP-A-0 326 213.
Amine oxides containing two hydrocarbyl groups with at least 14 C-atoms, such as dihardened tallow methyl amine oxide, are particularly preferred. Amine oxides have been found to provide particularly advantageous softening effects, furthermore compositions comprising amine oxides are generally easy to prepare, are stable and have an interesting creamy appearance.

Optional ingredients

Preferably, the compositions of the present invention contain substantially no anionic material, in particular no anionic surface active material. If such materials are present, the weight ratio of the cationic fabric softening agent to the anionic material should preferably be more than 5:1.
The composition can also contain one or more optional ingredients selected from non-aqueous solvents such as C₁-C₄ alkanols and polyhydric alcohols, pH buffering agents such as strong or weak acids eg. HCl, H₂SO₄, phosphoric, benzoic or citric acids (the pH of the liquid compositions ie preferably less than 5.0), rewetting agents, viscosity modifiers such as electrolytes, for example calcium chloride, antigelling agents, perfumes, perfume carriers, fluorescers, colourants, hydrotropes, antifoaming agents, antiredeposition agents, enzymes, optical brightening agents, opacifiers, stabilisers such as guar gum and polyethylene glycol, emulsifiers, anti-shrinking agents, anti-wrinkle agents, fabric crisping agents, anti-spotting agents, soil-release agents, germicides, linear or branched silicones, fungicides, anti-oxidants, anti-corrosion agents, preservatives such as Bronopol (Trade Mark), a commercially available form of 2-bromo-2-nitropropane-1,3-diol, dyes, bleaches and bleach precursors, drape imparting agents, antistatic agents, anti-redeposition agents, dye transfer inhibitors and ironing aids.
These optional ingredients, if added, are each present at levels up to 5% by weight of the composition. The pH of the composition is preferably 5 or below, or adjusted thereto.
Anti-redeposition agents particularly preferred in the compositions according to the invention are polymers. Suitable polymers include alkyl and hydroxoyalkyl cellulose ethers, such as methyl cellulose, and polyvinylpyrrolidone.
Silicones can be included in the compositions as the ironing aid, rewetting agent or the antifoaming agent. Suitable silicones for use in the compositions according to the invention include predominantly linear polydialkyl or alkylaryl siloxanes in which the alkyl groups contain one to five carbon atoms. The siloxanes can be amido or amino substituted. When the siloxane is amine substituted the amine group may be quaternised.
The compositions may also contain, in addition to the cationic fabric softening agent, other non-cationic fabric softening agents, such as nonionic fabric softening agents. Suitable nonionic fabric softening agents include glycerol esters, such as glycerol monostearate, fatty alcohols, such as stearyl alcohol, alkoxylated fatty alcohols C₉-C₂₄ fatty acids and lanolin and derivatives thereof. Suitable materials are disclosed in European Patent Application 88 520 (Unilever PLC/NV case C 1325), 122 141 (Unilever PLC/NV case C 1363) and 79 746 (Procter and Gamble). Typically such materials are included at a level within the range of from 0.5% to 10% by weight of the composition.

Liquid compositions

The total level of the three ingredients in a liquid composition is from 1 to 60% more preferred from 3 to 30% by weight of the composition. Based on the total weight of the three actives, the weight of the cationic softening agent is not more than 90%, preferably between 25 and 75 %, more preferred from 40 to 60 %. especially preferred about 50 %. The weight of the amine is not more than 70%, preferably between 10 and 60%, more preferred between 15 and 40 %, especially preferred about 25 %. The weight of the amphoteric material is not more than 60 %. If the amphoteric material is an amine oxide then this constitutes preferably less than 60 %, more preferred between 10 and 50 %, especially preferred between 15 and 40 %, most preferred about 25 % based on the weight of the three actives.
The optimum weight ratio of the three active components in the fabric conditioning composition depends on the level of anionic carried over from the wash cycle. We have found that a weight ratio of cationic fabric softener to amine to amine oxide of about 2:1:1 provides good results under most conditions of use.
The liquid compositions according to the inventions may be prepared by a variety of methods. One suitable method is to form a molten mixture of the cationic fabric softening agent, amine and amphoteric material, which is then added to water with stirring to form a dispersion and thereafter adding any optional ingredients.
In use, the fabric conditioning composition of the invention may be added to a large volume of water to form a liquor with which the fabrics to be treated are contacted. Generally, the total concentration of the cationic fabric softening agent, the amine and the amine oxide in this liquor will be between about 30 ppm and 500 ppm. The weight ratio of the fabrics to liquor will generally be between 40:1 and 4:1.
If the compositions of the invention are added to water which contains high levels of anionic surface active materials, a further improvement can be obtained if the compositions contain anionic scavengers such as low molecular weight cationics. Suitable materials include cationic compounds which have a solubility in water at pH 2.5 and 20°C of more than 5 g/l, preferably more than 10 g/l. Arquad 18 is a particularly preferred material. (Arquad 18 is a commercially available form of hardened tallow trimethyl ammonium chloride).
The invention will now be illustrated by the following non limiting Examples, where Examples 1A, 1B, 2A and 2B are included for comparison purposes only. In all of the Examples, all parts and percentages are by weight. Where commercially available materials are referred to, the percentages quoted are those of the active ingredient therein.

Examples 1-2

Compositions were prepared according to the formulations in the following tables. The compositions were prepared by comelting the cationic fabric softening agent, amine and amine oxide at 80°C. (When the amine was Armeen M2HT, the ortho phosphoric acid was added to the water prior to forming the co-melt. In contrast when ceranine HC39 was used, the acid was added after the components were dispersed). The comelt thus formed was added to water at 80°C and then soniprobed for a few minutes to form a disperion which was then cooled to room temperature.

The compositions were tested as follows -
40 grams of cotton terry toweling were washed for 5 minutes at 50°C with a commercially available washing powder product, UK Persil Automatic, in a litre of Wirral water (10°FH) in a tergotometer. 5 grams of the washing powder product was used. After separating the wash liquor, the fabric load was rinsed twice at 25°C with Wirral water. 4ml of a test composition was added to the second rinse. After line drying, the fabric load was assessed for softness by a panel of experts using a paired comparison test.

EXAMPLE NO.	1	1A	1B	2	2A	2B
Ingredient %
Arquad 2HT	2.5	2.5	-	2.5	2.5	-
Armeen M2HT	1.25	-	2.5	-	-	-
DHTMAO	1.25	2.5	2.5	1.25	2.5	2.5
Ceranine HC39	-	-	-	1,25	-	2.5
OPA	0.25	-	0.50	0.25	-	0.50
Water	-----balance-----

The results of the softness showed a preference for composition 1 over compositions 1A and 1B ie. the ternary system, containing the cationic, amine and amine oxide, gave the best softening. The same result was obtained when compositions 2, 2A and 2B were compared.
Compositions 1 and 2 were also compared. The results showed a preference for the product containing Ceranine HC39.

Examples 3-6

In these Examples, a comparison was made between ternary compositions in which the amine was either protonated or unprotonated. Compositions were prepared according to the formulations in the table by the method described above.

Example	3	4	5	6
Arquad 2HT	2.5	2.5	2.5	2.5
Armeen M2HT
(i) protonated with	1.25	-	-	-
OPA
(ii) not protonated	-	1.25	-	-
DHTMAO	1.25	1.25	1.25	1.25
Ceranine HC39
(i) protonated with	-	-	1.25	-
OPA
(ii) not protonated	-	-	-	1.25
OPA	0.25	-	0.25	-
Water	-----balance-----

The compositions were tested according to the method described in Examples 1 and 2.
The results show a preference for composition 3 which contained a protonated amine, over composition 4.
When Ceranine HC39 was the amine used, Examples 5 and 6, compositions containing the protonated and unprotonated material, gave similar results.
5 - A dihardened tallow methyl imidazolinium salt
7 - Hardened tallow trimethyl ammonium chloride
8 - Dicocodimethyl ammonium chloride
9 - Dihardened tallow imidazoline amine.

Examples 16-21

The following compositions according to the invention were prepared by the method described above

Example	16	17	18	19	20	21
Arquad 2HT	7.5	6.75	7.50	8.5	7.5	5.1
Ceranine HC39	3.75	3.375	3.75	-	-	8.5
Ceranine HCA	-	-	-	4.25	3.75	-
DHTMAO	3.75	3.375	3.75	4.25	3.75	3.4
Dobanol 25-9	-	-	1.00	-	-	-
OPA	0.75	0.22	0.75	0.85	0.75	0.70
Water	-----balance-----

Claims

An aqueous liquid fabric conditioning composition comprising from 1 to 60% by weight of a combination of:

(i) 20% to 90% by weight of a cationic quaternary ammonium fabric softening agent having two C_12-24 hydrocarbyl chains and a solubility in water at pH2.5 and 20°C of less than 10g/l;

(ii) 5% to 70% by weight of an amine; and

(iii) 5% to 60% by weight of an amphoteric fabric conditioning material wherein said amphoteric fabric conditioning material is selected from tertiary amine oxides of the following formula:
wherein:
a) R₂₅ and R₂₆ are C_8-24 hydrocarbyl chains, R₂₇ is an hydrocarbylgroup containing 1-4 carbon atoms or a group -(CH₂CH₂O)_nH and n is an integer from 1 to 6;

the percentage by weight of (i), (ii) and (iii) being based on the total weight of components (i), (ii) and (iii) in the composition.
A tabric conditioning composition according to claim 1, comprising based on the total weight of the three components (i) to (iii),

(i) 40 - 60% of cationic softening agent

(ii) 15 - 40% of amine

(iii) 15 - 40% of amine oxide.
A fabric conditioning composition according to any one of claims 1 or 2, comprising 3 - 30% by weight of active material.
Method for treating fabrics comprising the step of contacting fabrics with an aqueous bath comprising a fabric conditioning composition according to any one of claims 1 to 3, the total concentration of the cationic fabric softening agent, the amine and the amine oxide being between 30 and 500 ppm.