Granular compositions

Details Granular compositions Granular compositions

2001-05-11

2003-12-30

Hardee, John R (Department: 1751)

Cleaning compositions for solid surfaces, auxiliary compositions

With oxygen, halogen, sulfur, or nitrogen containing or...

C512S004000, C428S321100, C510S438000

Reexamination Certificate

active

06670311

ABSTRACT:

This invention relates to a granular composition and is particularly concerned with the production of a composition comprising granules with sufficient strength to withstand normal factory/processing handling coupled with the capability to carry a liquid phase, substantially water-free volatile organic active or functional ingredient, such as fragrances or perfumes, flavours, food ingredients and/or cosmetic ingredients. The functional ingredient may be a malodour compound, protein, enzyme, polysaccharide, carbohydrate or antibody. Suitable cosmetic ingredients include insect attractants or repellants, sunscreen compounds, or hair treatment compounds such as hair growth promoters, depilatory, hair straightening and permanent waving materials. The granules, for example, can carry perfume, retain the perfume within its pore system when formulated into a fabric washing powder and disperse, on contact with water, into particles small enough to prevent excess deposition on fabrics or other articles when used in a normal washing cycle. Such granules are intended to allow the intensity of the perfume in the washing powder to be maintained, suppress unwanted perfume loss and function as a delivery system to the wash and/or rinse cycle, fabric or other article.
Perfumes capable of modifying or enhancing the aroma of fabric washing compositions or imparting a more pleasant aroma are well known in the art. U.S. Pat. Nos. 4,131,555 and 4,228,026 are illustrative of prior art disclosing substances which impart a pleasing aroma or fragrance to liquid and granular fabric washing formulations. The described methods of adding the substance are mixing into the liquid formulation or spraying onto the surface of granular fabric washing compositions. It is well recognised that perfumes are volatile and many of the perfume ingredients can be lost from the product during processing or storage or destroyed or damaged by contact with alkaline conditions present in fabric washing compositions or by contact with some of the components of the composition, such as bleaches and enzymes.
Attempts to solve these problems have centred around the use of carriers impregnated with the perfume. EP-A-332259 (Proctor and Gamble) discloses certain perfume particles formed by adsorbing a perfume onto silica. EP-A-332260 (Proctor and Gamble) describes the use of such particles in fabric softening compositions. International Application No. WO94/16046 (Quest International) discloses the use of highly structured precipitated and gel type silicas to convert liquid perfume to a free flowing powder which can be readily formulated into a concentrated fabric washing formulation. In all these prior art examples emphasis is placed on particle size, total pore volume and surface area of the silica particulate since adsorption capacity is of prime importance. EP-A-332259 and EP-A-332260 describe a wide range of silicas with a particle size from 0.001 micron (fumed silica) through to 15 micron (silica gel) and a surface area ranging from 100 to 800 m
2
/g. For a fabric washing composition the preferred silica is a fumed silica, with a particle size in the range 0.007 to 0.025 micron. Mention is also made that silica gels may be used, the preferred size being 1 to 8 micron. International Application No. WO94/16046 discloses silicas with a particle size of 5-50 microns and a surface area ranging from 100 to 450 m
2
/g.
EP-A-820762 (Unilever) describes porous silicas which are useful in fabric washing powders and having a particle size greater than 50 microns and a surface area in the range from 100 to 450 m
2
/g. All of the aforementioned prior art makes no reference to the capability of the adsorbent to carry and retain fragrance through the processing steps used in the manufacture of a fabric washing powder.
EP-A-535942 and EP-A-536942 (Unilever) describe porous inorganic carrier particles, for example silica having at least a pore volume of 0.1 ml/g consisting of pores with a diameter 7 to 50 Å which are stated to be capable of carrying and retaining fragrances. A wide range of particle size is claimed from at least 5 microns up to 500 microns, and it is also disclosed that particles in this size range can also be formed into aggregates of two or more particles to make aggregates of several particle diameters, for example 1000 microns. However, no mention is made as to how this will be achieved and to the properties of the resultant agglomerated particles. It is not certain, for example, from the description of the invention that agglomerates of the preferred particles would still be able to retain fragrance and suppress loss thereof through evaporation. What is certain is that the inorganic carriers referred to, for example microporous silica gels and zeolite Y, have low total porosity and hence poor carrying capacity.
The formation of granules by the agglomeration of finely divided silica has been described in International Patent Applications Nos. WO94/12151 (Unilever) and in WO96/09033 (Crosfield). The former refers to materials suitable for cleansing skin and hair and utilises silica particles which can carry but do not retain fragrance or suppress its evaporation, whilst the latter describes how silicas of mixed structures can be brought together to form agglomerates suitable for imparting a sensory effect to toothpaste.
U.S. Pat. Nos. 5,656,584 and 5,648,328 (Proctor and Gamble) describe processes for producing a particulate laundry additive composition in the form of granules or agglomerates. The process includes mixing the porous carrier, zeolite X and/or zeolite Y or mixtures thereof, typically containing the perfume with an encapsulating material, typically a carbohydrate, and then compacting (U.S. Pat. No. 5,656,584) or extruding (U.S. Pat. No. 5,648,328) the mixture to form agglomerates. The preferred inorganic materials zeolite X and zeolite Y will retain and suppress the fragrance but they have poor carrying capacity when compared with a high porosity silica (pore volume of at least 1 ml/g).
There is a need, therefore, for a granular composition comprising granules having sufficient strength to withstand normal factory/processing handling, the capability to carry a liquid phase, volatile organic, substantially water-free functional ingredient such as perfume, preferably at loadings of at least 30% by weight, to retain the functional ingredient within its pore structure while suppressing evaporative loss and to disperse into particles on contact with water.
According to a first aspect of the present invention there is provided a granular composition for carrying and retaining a liquid phase, substantially water-free, volatile organic functional ingredient, said granular composition comprising at least 40% by weight of an amorphous silica having a surface area of at least 550 m
2
/g, a pore volume from about 1.0 to about 2.5 ml/g and a particle size of no more than 50 microns (preferably no more than 40 microns and more preferably no more than 30 microns), the granules of said composition disintegrating when contacted with water and having:
a particle size greater than about 200 and up to about 2000 microns, preferably from about 400 to about 1200 microns; and
a dry strength such that no more than about 30%, more preferably no more than about 25% and most preferably no more than about 20%, by weight pass through a 212 micron sieve when subjected to the attrition test defined herein.
Typically the amorphous silica constitutes up to about 70% by weight of the composition and the functional ingredient comprises at least 30% by weight of the composition, for instance the functional ingredient may constitute up to-about 60% by weight of the composition.
Preferably the granule composition is such that, on contact with water, from about 50%, preferably from about 60% to about 95% by weight will pass through a 212 micron sieve.
The silica granules preferably have, with respect to the functional ingredient, an absorption capacity of at least 30%, more preferably at least 35%, most preferably at least 40% by weight. Th

Affiliated with

Also associated with

Rating

Granular compositions does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Granular compositions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Granular compositions will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3154997