This invention relates to liquid formulations capable of depositing perfumes on fabric surfaces. The formulation may be used in diluted form and examples of the fabric surfaces are cotton, wool, polyacrylic, polyamide and polyester fibres. These formulations are intended for use in the rinse cycle of a fabric cleaning operation.
The liquid formulations of the invention will normally be used to provide a fabric softening effect.
Perfumes are liquid compositions consisting of a number of organic compounds, capable of appreciation by smell. The compounds are usually derived from natural sources but synthetic materials are also used. Formulations intended for the laundering of fabric will normally contain a perfume to provide a pleasant after smell on the laundered fabrics. Thus powder and liquid detergent formulations, and rinse cycle formulations contain perfumes.
It is desirable to have the perfume in a fabric treatment formulation used efficiently because it is a relatively high cost component of any formulation. In use the perfume will be present in the formulation at a relatively low concentration and dilution will cause the fabric to be in contact with a liquid system containing a very low concentration of the perfume.
The desirability of enhancing the effectiveness of perfumes has been acknowledged in the patent literature. United States Patent Specification No. 4 152 272 (Young) describes a fabric conditioning composition comprising particles of a wax-like carrier and a perfume. British Patent Specification No. 1 544 863 (Schilling et al) describes a fabric conditioning composition for use in an automatic laundry dryer comprising particles of a mixed cationic/non-ionic carrier and a perfume. In German patent application No. 2 732 985 of Unilever Limited a deposition system is described which provides increased deposition of materials providing a perceivable effect, for example perfumes. Amines are disclosed as matrix materials, but a cationic material is required as an essential component of the dispersed phase including the perceivable component.
We have now discovered that surprising good perfume deposition on fabrics can be achieved without the incorporation of cationic materials in perfume-carrying amine particles. Thus, according to the invention, there is provided a liquid formulation for depositing perfumes on fabric surfaces, wherein the formulation comprises an aqueous base having:
- i) a first dispersed phase constituting from about 0.5% to about 50% by weight of the formulation and consisting of particles having an average size of from about 0.1 micron to about 200 microns, preferably 0.1 to 5.0 micron, the particles comprising an intimate mixture of (a) from about 0.5% to about 50% by weight, based on the weight of the particles, of a perfume, and (b) from about 50% to about 99.5% by weight, based on the weight of the particles of a matrix comprising at least one water dispersible amine of the formula
R - N R1 R2. where R is an alkyl or alkenyl group having from 8 to 22 carbon atoms, is hydrogen or an alkyl or alkenyl group having 1 to 4 carbon atoms and R2 is hydrogen or an alkyl, alkenyl or amino-alkyl group having from 1 to 22 carbon atoms, the matrix containing no added cationic material; and - ii) a second dispersed phase constituting from about 0.5% to about 30% by weight of the formulation and comprising a fabric conditioning agent.
The aqueous base will contain water as a major constituent. While it is possible for this to be the sole component of the base, the latter will usually include other materials, for example, electrolytes, buffering agents, short chain alcohols, emulsifiers, colouring materials, bactericides, antioxidants, surface active agents and fluorescers.
The alkyl groups, alkenyl groups and alkyl portion of the amino-alkyl groups may be linear or branched.
Preferably the amine is a primary or tertiary compound or a diamine, particularly a diamine of the formula R-NH-(CH2)3-NH2, where R is as defined above. Preferred compounds are methyl dihardened tallow tertiary amine, hardened tallow primary amine, methyl, dicoco-tertiary _amine, coco primary amine and N-alkyl 1:3 propylene diamines, where the alkyl group may be hardened tallow, coconut or C18/C20 mixture. The amines of utility in the invention can be solid, liquid or pasty and will have a solubility in water of not more than about 1% weight/ volume. The amines will be dispersible in the aqueous base liquid.
The fabric conditioning agent may be selected from the classes of:
- dialkyl quaternary ammonium salts e.g. distearyl dimethyl ammonium chloride;
- amine salt derivatives;
- amphoteric compounds e.g. alkyl sulphobetaines and imidazoline derivatives;
- agents formed by complexing cationic and anionic species, e.g. as described in UK patent specification 2 007 735.
A list of suitable conditioning materials is given in German application 2 732 985.
The perfume may be selected from any perfumes and any mixtures thereof. Examples of fabric substantive perfumes suitable for use in the present invention are listed in S Arctander, Perfume Flavors and Chemicals, Volumes I and II, published by the author, Montclair, New Jersey, USA and the Merck Index, 8th Edition, Merck & Co. Inc., Rahway, New Jersey, USA. Deodorant perfumes such as disclosed in United States specification 4 134 838 may also be used.
A method of preparing the liquid formulation of the invention, includes the step of forming a liquid mixture of the amine and the perfume and dispersing the mixture in water.
The preferred method is to melt the amine and the perfume together and then disperse the mixture in heated water. An aid to dispersion e.g. high speed stirrers, ultrasonic agitators, vibrating reeds and continuous mixers may be used. In an alternative method the melt -is solidified in bulk and then dispersed into water at ambient temperature.
Examples of formulations according to the invention will now be given. The benefit achieved by use of the invention is demonstrated using the following test method:
- Three pieces of 20 cm x 20 cm terry towelling (T) or bulked acrylic (BA) were rinsed in a Terg-o-Tometer (a Registered Trade Mark) for 4 minutes at 75 cycles per minute agitation. The rinse liquor was formed by adding 2 mls of formulation to 800 mls of water. The samples were spun dry for 30 seconds and dried overnight. The perfume effect was then gauged by an experienced panel and graded, from 0 to 5. The average grade was taken for each formulation.
0.9 g of methyl di-hardened tallow amine was melted and 0.2 g of a perfume added; the amine was maintained as . near to its melting point as possible consistent with good mixing. The melt was then added to 50 g water at 700C and a dispersion formed with the aid of an ultrasonic probe. The average particle size was 0.4 microns. Dimethyl di-hardened tallow ammonium chloride (5 g) was dispersed in water (50 g) and the two dispersions mixed.
The perfume effect was gauged and compared to a control formulation. This control was formed by dispersing 5 g of the above quaternary ammonium salt in water (100 g) and adding 0.2 g of the same perfume.
The results of this and the following Examples 2-14 are given in the Table I which quotes the average grading for each formulation and defines the amine used by chain length of the alkyl group and type of amine.
Example 1 was repeated using methyl dicoco amine.
Example 1 was repeated using methyl di(C18/C20) alkyl amine. The long chain alkyl group was formed by a 50:50 molar mixture of C18 and C20 alkyl chains.
Example 1 was repeated using hardened tallow primary amine.
Example 1 was repeated using coconut primary amine.
Example 1 was repeated using C18/C20 primary amine.
Example 1 was repeated using di-hardened tallow secondary amine.
Example 1 was repeated using di-coconut secondary amine.
Example 1 was repeated using dimethyl mono hardened tallow tertiary amine.
Example 1 was repeated using dimethyl mono-coconut tertiary amine.
Example 1 was repeated using dimethyl mono (C18/C20) alkyl tertiary amine.
Example 1 was repeated using N-hardened tallow 1:3 propylene diamine.
Example 1 was repeated using N-coco 1:3 propylene diamine.
Example 1 was repeated using N-(C18/C20) 1:3 propylene diamine.
Example 'I was repeated using a number of perfume/ -amine combinations and the results were compared with two controls. Control A was an aqueous dispersion of non- ionic/cationic/perfume particles according to our German Patent Specification No. 2 732 985 containing the same quantity of perfume (0.2 g), where the non-ionic was tallow alcohol 3EO (0.9 g) and the cationic was Arosurf TA 100 (dimethyl distearyl ammonium chloride)(0.05 g). Control B consisted of the same quantity of perfume dispersed in water.
The amines used were:
The results are given in the following table II:
The perfume formulations used were: