Rinse conditioner

Abstract: A powdered rinse conditioner comprising a nonionic active water insoluble cationic active having the formula: in which R₁ is independently selected from C₁₋₄ alkyl, hydroxyalkyl, or C₂-C₄ alkenyl groups and wherein each R₂ group is independently selected from C₂₋₂₇ alkyl or alkenyl groups and n is an integer for 0 to 5. The rinse conditioner exhibits good softening results when added directly to the wash liquor.

Description: This invention relates to rinse conditioners comprising a softening or anti-static component delivered directly to the wash liquor during a rinsing step. In the past fabric conditioning has been carried out either during then rinsing step of a fabric washing and rinsing process or during tumble drying of the fabric. In almost all cases rinse conditioning is accomplished by adding a liquid dispersion of a rinse conditioning agent to the rinse liquor. The liquid dispersion was traditionally distributed and made available to consumers as a ready to use aqueous dispersion. More recently, concern for the environment and consumer convenience has led to the sale of concentrated aqueous dispersions which are either used in smaller amounts or are mixed with water to form a predilute before use. Fabric softening compositions comprising ester linked quaternary ammonium compounds and C 8 -C 28 fatty acid material or salts thereof have been described in EP-A-409 502 (Unilever). In EP-A-234082 it has been proposed to supply rinse conditioner as a solid block. This approach requires the use of a special restraint for the block and may also require the modification of the washing machine to enable the block to be dissolved and dispensed by a spray system. Various proposals have been made to supply fabric softener in granular or powdered form. EP 111074 is typical and uses a silica to carry the softener. A disadvantage of using a carrier such as silica is that it bulks up the product and serves no function beyond making the powder compatible with other ingredients that may be contained in a washing powder. WO 92/18593 describes a granular fabric softening composition comprising a nonionic fabric softener and a single long alkyl chain cationic material. The specification teaches that effective cationic softening compounds when used in granular form exhibit poor dispersion properties. For these reasons, despite the obvious environmental and transport saving advantages of selling a water free powdered rinse conditioner, manufacturers have not done so. According to the present invention there is provided a powdered rinse conditioner comprising: a) a water insoluble cationic active having the formula: wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5 and b) a nonionic dispersing agent chosen from alcohol ethoxylates. The invention also describes the use of a powdered rinse conditioner for direct application to the rinse load comprising a nonionic dispersing agent chosen from alcohol ethoxylates and a water insoluble cationic active of the formula: wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5 The invention further comprises a method of delivering a powdered rinse conditioner by adding the composition directly to the rinse liquor of a wash load, said rinse conditioner comprising a nonionic dispersing agent chosen from alcohol ethoxylates and a water insoluble cationic active having the formula: wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5. Preferably powdered rinse conditioner of this invention should be used when rinsing in by hand or using a twin tub or top loader washing machine as these rinsing methods enable the fabric conditioner to be manually dosed at the final rinse stage. It is advantageous for good dissolution if the temperature of the rinse water is above 10°C, preferably above 20°C. However an acceptable level of softening is achieved below 10°C. Preferably the cationic active comprises more than 40% by weight of the powder and less than 95% by weight of the powder. The powder may also contain a co-active at levels of up to 20%. Preferred co-active are fatty acids. It is preferred if from about 1 wt% to about 15 wt% of fatty acid is present in the composition to boost softening. Ideally the ratio of cationic active:fatty acid is greater than 6:1. More preferably the ratio of cationic:fatty acid is 12:1. The nonionic active is present in the composition as a dispersion aid which further boosts softening, it is preferred if the nonionic active is chosen from the group consisting of alcohol ethoxylates, preferably long chain alcohol ethoxylates. Preferably the levels of nonionic dispersing agent is between 5 wt% and 20 wt%. Advantageously the powder may also contain a flow aid and other ingredients commonly found in rinse conditioners such as perfume, antifoam, preservative and dye. It is advantageous for environmental reasons if the quaternary ammonium material is biologically degradable. Preferred examples of the quaternary ammonium material such as 1-trimethylammonium-2,3-dihardened tallowoyloxy propane chloride (HT TAMPC) 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-tallowoyloxy, 2-hydroxytrimethyl ammonium propane chloride. The composition may further comprise a fatty acid coactive and may comprise hardened tallow fatty acid. However, the level of fatty acid should be kept as low as possible, preferably less than 15%, to minimise the reduction of softening performance in the case that there is carry-over of anionic active from the earlier washing part of the fabric washing and rinsing process. The invention will now be described with reference to the following non-limiting examples: Example 1, A A powder having the following composition was prepared by melting the ingredients together and allowing the mixture to re-solidify followed by grinding to a particle size between 150-250 µm. Example 1 Component (% active as received) Weigth % in Product Supplier Chemical Name 1. HT TMAPC 80.7 Hoechst 1-trimethyl ammonium-2,3-dihardened tallowoyloxy propane chloride. 2. Hardened tallow fatty acid* 6.2 Hoechst Hardened tallow fatty acid 3. Genapol C-100 (100%) 4.7 Hoechst Coco alcohol with 10 mols ethoxylation 4. Perfume (LFU 384P) 3.4 Quest 5. Microsil/GP 4.2 Crosfields Aluminosilicate The Genapol C-100 nonionic is chosen for its biodegradability. The Microsil is included as a flow aid. Example 1 was compared with a commercial granular rinse product known as "Myoshi stick" (Example A). The formula of Example A is described below Example A Component % weight Chemical Name Arquat 2HT (Trademark) 13.6 dihardened tallow dimethyl ammonium chloride Cocobenzyl di methylammonium chloride 8.2 - Urea 78.2 - The dosage of each product was adjusted so that they were dosed at equal active level, 0.1% cationic on weight of fabric (o.w.f). The compositions were used in the final rinse of test clothes under the following test conditions. Test i) The wash load consisted of a 50/50 mixture (by weight) of terry towelling and polyester cotton. 2.4 dm 3 of 4°FH water (1°FH = 10 ppm as CaCO 3 ie. 10 -4 M) was added to a bucket and 7.2g of a commercial South African washing powder added and stirred (3.0g washing powder/litre water). 80g of terry towelling (6 monitors, 8, 7.5x 7.5 cm) and 80g of polyester cotton was added to the bucket. The cloths were soaked for 20 minutes and then agitated for 5 minutes by hand. The cloths were removed from the bucket and squeezed to remove excess water. The cloths were returned to the bucket containing 2.4 dm 3 of fresh water (no main wash product added) and rinsed by agitating by hand for a further 2 minutes. The clothes were removed, squeezed by hand and the rinse process repeated with fresh water. The relevant rinse treatment was added at the third rinse stage on top of the cloths. The cloths were agitated for a further two minutes with the rinse products after which they were once more squeezed out and finally line dried overnight. Test ii) Liquor:cloth was 5:1. The wash regime was identical to that described above for test i) with the following exceptions:240g of terry towelling (8 monitors, 7.5 x 7.5 cm) and 240g of polyester was used as the wash load. Test iii) The wash load consisted of a 2kg load of 50/50 mixture of cotton terry towelling and cotton sheeting. The wash load was placed in Japanese twin tub and washed for 5 minutes in water at 25°C using a commercial Japanese washing powder (3.0g/litre). The wash load was then subjected to a running rinse and then treated with the relevant rinse treatment for 5 minutes. The wash load was spun and finally line dried overnight. Softening Assessment Softening scores were assessed. An expert panel of 4 people using a round robin paired comparison test protocol. Each panel member assessed four sets of test cloths. Each set of test cloths contained one cloth of each test system under evaluation. Panel members were asked to pick the softer cloth of each pair during evaluation. A "no difference" vote was not permitted. Softeners scores were calculated using an "Analysis of Variance" technique. Higher values are indicative of better softening. The softening scores for each testing method are shown in table 3. In this test the higher the scores the softer the cloth. Softening Preference Score (no. of votes) Example 1 Example A Test i) 28 6 Test ii) 24 16 Test iii) 2 mins 24 14 The formulation comprising HT TMAPC clearly has better softening performance of fabrics that the formulation comprising Arquad 2HT. Examples B, C, and 2 A base composition comprising 3.92g (0.007 mol), Genapol C-100 (trademark ex Hoescht), 4.75g perfume (LFU 384P trademark ex Quest) and 5.00g Microsil (trademark ex Crosfields) was prepared. To this 0.14 mol of the following actives were added Example B Tetranyl AHT (trademark) (130.45g of 85% active) Example C Adogen 442-100P (trademark) (80.50g of 83% active) Example 2 HT TAMPC (117g of 85% active) Softening performance was evaluated for Examples B, C and 2 by adding O.llg of the softening active composition to 1 litre of tap water, at ambient temperature containing 0.001% (w/w) sodium alkyl benzene sulphonate (ABS) in a tergotometer. The ABS was added to simulate carryover of anionic detergent from the main wash. Four pieces of terry towelling (20cm x 20cm, 50g total weight) were added to tergotometer pot. The cloths were treated for 5 minutes at 80 rpm, spin dried to remove excess liquor and line dried overnight. Softening of the fabrics was assessed by an expert panel of 4 people using a round robin paired comparison test protocol. Each panel member assessed four sets of test cloths. Each set of test cloths contained one cloth of each test system under evaluation. Panel members were asked to pick the softer cloth of each pair during evaluation. A "no difference" vote was not permitted. Softness scores were calculated using an "Analysis of Variance" technique. Higher values are indicative of better softening. Table 4 shows the softening scores. Example Preference Scores Softening Scores B 12 5.25 C 10 5.00 2 26 4.25 The higher the preference score, the lower the standard score and the softer the cloth. It is shown in table 4 that a powdered composition containing HT TAMPC gives better softening than compositions comprising other cationic softening ingredients. Example 3 Component Weight % in product Supplier Chemical Name HT TMAPC * 72.7 Hoescht 1-trimethyl ammonium-2,3 dihardened tallowoyloxy propane chloride Fatty acid* 3.1 Hoescht Hardened tallow fatty acid IPA * 13.8 Hoescht propan-2-ol Genapol C100 (Trademark) 3.0 Hoescht Coco alcohol ethoxylated with 10 mols ethylene oxide Perfume 3.6 Quest Microsil (Trademark) 3.8 Crosfields Aluminosilicate HT TMAPC*, fatty acid*, and IPA* were supplied as a continuous solid by Hoescht. The powder of Example 3 had the initial composition as shown in table 5. The powder was prepared using a dry mix process. The dry mix process involves mixing the ingredients together followed by grinding for 2 to 5 minutes. The powder was sieved to provide a particle between 150-250 µm. The powder was tested for its softening properties using the same testing method as for Example 1. The results are shown in table 6. water at 7°C water at 20°C powder powder Softening Score 5.00 3.5 Water would be expected to give a softening score of 8.

Claims: A powdered rinse conditioner comprising: a) a water insoluble cationic active having the formula : wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5 and b) a nonionic dispersing agent chosen from alcohol ethoxylates. A rinse conditioner according to claim 1 in which the nonionic dispersing agent is a long chain alcohol ethoxylate. A rinse conditioner according to claim 1 or claim 2 in which the water insoluble cationic active is 1-trimethyl ammonium-2,3-dihardened tallowoyloxy propane chloride A rinse conditioner according to any preceding claim in which the cationic active comprises more than 40% by weight of the powder. A rinse conditioner according to any preceding claim in which the level of nonionic dispersing agent is between 1 wt% and 20 wt%. A rinse conditioner according to any preceding claim which further comprises between 1 wt% and 15 wt% fatty acid. Use of a powdered rinse conditioner for direct application to the rinse load comprising a nonionic dispersing agent chosen from alcohol ethoxylates and a water insoluble cationic active of the formula: wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5. A method of delivering a powdered rinse conditioner by adding the composition directly to the rinse liquor of a wash load, said rinse conditioner comprising a nonionic dispersing agent chosen from alcohol ethoxylates and a water insoluble cationic active having the formula: wherein each R 1 group is independently selected from C 1-4 alkyl, hydroxyalkyl or C 2 -C 4 alkenyl groups; and wherein each R 2 group is independently selected from C 2-27 alkyl or alkenyl groups and n is an integer from 0-5.

Inventors: TURNER GRAHAM ANDREW, TURNER, GRAHAM ANDREW, TURNER, GRAHAM ANDREW, UNILEVER RESEARCH
Applicants: UNILEVER NV, UNILEVER PLC, UNILEVER N.V.
Application year: 1993
Main classification: C11D1
IPC codes: C11D1, C11D11, D06M13, D06M23, C11D10, C11D3