This invention relates to a bleaching composition comprising a bleach in a water solution forming a water phase, characterized by a separate organic phase comprising a fragrance. The fragrance present in the organic phase is not stable under oxidative conditions.
The present invention relates to a bleaching composition comprising a bleach in a water solution forming a water phase.
Bleaching compositions have a rather unpleasant odor. The odor improving of bleach compositions is an unsolved problem until now. Due to the inherent characteristics of bleaches to oxidize fragrances, it is difficult to scent a bleaching composition in such a way that the odor of the fragrance remains stable. The fragrance has to be compatible and stable under highly oxidative conditions as well as show a good consumer acceptance. Amongst the fragrances which are available to the perfumers, only a few (less than 20) are sufficiently stable under such conditions. Presently the only formulation comprising stable fragrances in the presence of sodium hypochlorite exhibit agrestic, piney odors. Moreover the fragrance dosage is limited to 0.1% due to chlorine stability and solubility.
Bleaches are substances which lighten or whiten a material by chemical reaction. This can involve either oxidative or reducing reactions. E.g. decolorization can often be achieved by destroying one or more of the double bonds in the conjugated ring system of a chromophor.
PCT/US98/02897 discloses a solid fragrant bleaching block as well as methods for making and employing such a block. Said block comprises a fragrance which is stable to the bleach, does not decompose the bleach and is not substantially hygroscopic.
It is an object of the present invention to provide a stable liquid bleaching composition.
Surprisingly it has been found that a bleaching composition comprising a bleach in a water solution forming a water phase, characterized by a separate organic phase comprising fragrance has an outstanding odor stability. The composition of the present invention allows to have all kinds of fragrances, therefore new odor directions such as compositions exhibiting a floral, woody or fruity odor. Compositions according to the present invention comprising fragrances having a woody characteristic like georywood, sandalwood notes, peonile and ionone have been found to be stable after aging in the two phase system. Said fragrances are oxidizable by bleaches and therefore not stable in traditional mono phase products.
A further advantage of the composition according to the present invention is that the bleach is stable over time as well due to the two phase system.
In a preferred embodiment the composition according to the present invention comprises 2 to 30% (v/v) of the organic phase and 70 to 98% (v/v) of the water phase. Compositions according to the present invention comprising 10% (v/v) of the organic phase and 90% (v/v) of the water phase are especially preferred.
The main component of the organic phase of the composition according to the present invention is preferably a linear or branched alkane having 5 to 16 carbon atoms or a mixture of such alkanes. These alkanes are preferred due to their characteristic of being not miscible with water and their high evaporation rate, which guarantees that they do not disturb the odor of the fragrance.
The bleaches which may be employed in the present invention may be selected from a wide variety of known compounds. Preferably, the bleaches is selected from the group of chlorine containing bleaches, peroxides and reducing bleaches. The chlorine containing bleaching compounds may be selected from the group of chlorine, hypochlorite, and chlorite as well as chlorine dioxide. In a most preferred embodiment of the present invention sodium hypochlorite is used in the presence of sodium hydroxides. The composition according to the present invention comprises preferably 1 to 5% by total weight of the active chlorine.
The composition of the present invention allows to have all kinds of fragrances. In a composition according to the present invention a fragrance may be used alone or in combination with further fragrances of natural and/or synthetic origin. The term "fragrance" is used within the context of the present invention for a compound or a mixture of compounds which stimulate/s the sense of smell. The range of the natural fragrances includes in addition to readily volatile, also moderately and only slightly volatile components. The synthetic fragrances embrace representatives from practically all classes of fragrance substances.
A further advantage of the composition according to the present invention is the possibility of higher fragrances concentrations in the product. Due to the two phase system a fragrance concentration of 0.1% up to 2% or even more can be solved.
Perfumery raw materials were tested for a period of 1 month at 37°C and evaluated each week. The dosage of perfumery raw material was 0.2%. Stability tests were shaken twice a week during the test in order to simulate the real in use conditions. Stability tests results are compiled into the following tables.
A fragrance tested in the bleaching composition with a water and an organic phase for a period of 1 month at 40°c.
The fragrance comprises agrumex, decalactone gamma, manzanate, tetrahydolinalol, peonile, galbanone, diphenyloxide, damascenone total, galaxolide and hexyl isobutyrate.
Olfactive stability was assessed after ageing. Quality and intensity of fragrance composition were judged stable.
Chlorine stability results are summarized below.