Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Patent
1999-11-09
2000-12-12
DelCotto, Gregory R.
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
510326, 510349, 510356, 510394, 510446, 510452, 510456, C11D 172, C11D 342
Patent
active
061599204
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a novel detergent composition and a process for preparing the same, and in particular to the provision of a laundry composition having improved whiteness as perceived by the consumer.
BACKGROUND OF THE INVENTION
The use of whitening agents, or brighteners, in laundry applications to whiten fabrics has been widespread since the mid-1970s. Since then, much research has been carried out into the properties of such whitening agents, and many different compositions including such agents have been described in the literature. However, most applications of whitening agents have been for the purpose of fabric whitening, rather than whitening of the detergent composition itself.
WO 94/05761 discloses a process for preparing a high density granular detergent composition in which the bulk density of the detergent composition is increased by spraying detergent particles with a liquid and then dusting with a fine powder in a rotating drum or mixer. It is preferred that the liquid comprise a nonionic surfactant. Optionally, the liquid may also include other ingredients, such as perfume or a slurry, in water, of an optical brightener. The Examples describe the use of a 20% aqueous solution of optical brightener.
However, a problem with mixing a nonionic surfactant with water is that this can lead to the formation of flakes of nonionic surfactant which tend to block the spray nozzle, thereby interrupting the process and requiring cleaning of the nozzle before the process can re-start. Furthermore, the use of an aqueous spray tends to be detrimental to the stability of the final detergent composition because water tends to react with and/or promote reaction of components of the composition.
JP-A-07286198 discloses a process for preparing a granular nonionic detergent composition comprising spray-drying detergent particles containing 1% by weight of a nonionic surfactant and 0.01% by weight of a brightener. The brightener is first dissolved and/or dispersed in the nonionic surfactant, and is then granulated with other ingredients to form detergent particles prior to spray-drying. The process is designed to prevent unevenness of fluorescence of textile articles during washing.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention, a detergent composition comprises detergent particles, each particle having a substantially anhydrous coating comprising a fluorescent whitening agent and a nonionic surfactant.
The composition of the present invention has improved whiteness properties, even with very low levels of whitening agent, as compared to a composition in which the whitening agent is present throughout the detergent particles, as disclosed in JP-A-0728198, discussed above.
According to a second aspect of the present invention, a process for preparing a detergent composition comprises spraying detergent particles with a substantially anhydrous mixture comprising a fluorescent whitening agent and a nonionic surfactant.
As the process of the present invention substantially excludes the presence of water during spraying of the whitening agent
onionic surfactant mixture, it overcomes two major problems experienced in the prior art when spraying nonionic surfactant when wet. In addition, a dramatic increase in the whiteness of the resulting product is observed.
According to a third aspect of the present invention, the use of a substantially anhydrous mixture comprising a fluorescent whitening agent and a nonionic surfactant improves the whiteness properties of detergent particles, when the detergent particles are sprayed with the said mixture.
DESCRIPTION OF THE INVENTION
Prior to spraying the detergent particles, a substantially anhydrous mixture of whitening agent and nonionic surfactant is prepared by dispersing or partially dissolving the whitening agent in the nonionic surfactant, preferably with mixing to achieve a substantially homogenous mixture. The homogeneity of the mixture may be assessed using, for example, a UV lamp, thereby d
REFERENCES:
patent: 4869843 (1989-09-01), Saito et al.
patent: 5000869 (1991-03-01), Dittert
patent: 5560748 (1996-10-01), Suruzidis et al.
patent: 5958858 (1999-09-01), Bettiol et al.
patent: 5998351 (1999-12-01), Brouwer et al.
Delcotto Gregory R.
Dressman Marianne
Miller Steven W.
The Proctor & Gamble Company
Zerby Kim William
LandOfFree
Sprayed granule does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sprayed granule, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sprayed granule will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-216939