Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – Specific organic component
Reexamination Certificate
1999-03-02
2001-02-20
Gupta, Yogendra (Department: 1751)
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
Specific organic component
C510S117000, C510S276000, C510S290000, C510S308000, C510S477000, C510S478000, C510S515000
Reexamination Certificate
active
06191100
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a detergent composition comprising cationic and anionic surfactants and an acid and alkali source, which is suitable for use in laundry washing and dish washing methods.
BACKGROUND TO THE INVENTION
There is a trend amongst commercially available granular detergents towards higher bulk densities and towards granular detergent compositions which have a higher content of detergent active ingredients, such as various surfactants. Such detergents offer greater convenience to the consumer. The desire for such concentrated products ensures that the amount of filler materials are reduced and packaging materials which, ultimately, be disposed of.
Amongst consumers there is also a need for detergents which provide improved cleaning and stain removal. Therefore, in the recent past detergents have been developed which contain high levels of surfactant and various types of surfactants, such as anionic, nonionic and cationic surfactants.
The high density detergents, comprising high levels of surfactants can lead to poor solubility properties, arising from low rate of dissolution or the formation of gels, and thus to poor dispensing of the product, either from the dispensing drawer of a washing machine, or from a dosing device placed with the laundry inside the machine. This poor dispensing is often caused by gelling of particles, which have high levels of surfactant, upon contact with water. The gel prevents a proportion of the detergent powder from being solubilized in the wash water which reduces the effectiveness of the powder. This is a particular problem at low water pressures and/or at lower washing temperatures.
WO94/28098 discloses a non-spray-dried detergent powder comprising a combination of an ethoxylated primary C8-18 alcohol, an alkali metal aluminosilicate builder and 5 to 40 wt % of a water-soluble salt of a citric acid. EP-A-0 639 637 discloses the replacement of perborate bleach with an alkali metal percarbonate to improve the dispensing profile and dissolution rate of a detergent. Citrate or mixtures of citrate with sulphate or carbonate can be used to coat the percarbonate bleach. EP-A-0 639 639 contains a similar disclosure in this respect.
The use of effervescence to improve the dispensability of granular materials has been used extensively in pharmaceutical preparations. The most widely used effervescent system in this respect is citric acid in combination with bicarbonate. This effervescent system has also been described for improving the dispersibility of pesticidal compositions for controlling water-borne pests, e.g. GB-A-2,184,946.
EP-A-0 534 525 discloses the use of particulate citric acid with a specified particle size range of 350 to 1500 microns.
U.S. Pat. No. 5,114,647 discloses a sanitising composition comprising granules of alkali metal carbonate and aliphatic carboxylic acid of a particle size of 150 to 2,000 microns.
EP-A-0 333 223 discloses a bathing preparation comprising fumaric acid having an average particle size of 50-500 microns.
The addition of citric acid results in a reduction in alkalinity. However, an alkaline pH is required for an optimum performance of various detergent ingredients, such as certain surfactants. Overall an alkaline pH promotes cleaning, stain removal and soil suspension. Therefore, the incorporation of acids into detergent compositions is undesirable. For example, U.S. Pat. No. 4,414,130 discloses detergents, comprising organic acids, wherein certain compounds such as cationic surfactants are preferably omitted.
The Applicants now have found that the particular problems associated with dispensing a detergent composition comprising anionic and cationic surfactants can be improved by the inclusion of an acid and an alkali source whilst the performance of the cationic and anionic surfactants is maintained. This eliminates or reduces the problems of solid detergent particles remaining in the washing machine and on washed clothes.
Furthermore, since the surfactants are more efficiently dispensed into the wash water, the overall performance of the surfactants is more efficient and an overall improved cleaning, stain removal and soil suspending can be achieved.
Furthermore, the detergent residues in the dispensing drawer or dispensing device are reduced.
All documents cited in the present description are, in relevant part, incorporated herein by reference.
SUMMARY OF THE INVENTION
According to the present invention there is provided a detergent composition comprising an anionic surfactant, present at a level of from 0.5% to 60% by weight, a cationic surfactant, present at a level of from 0.01% to 30% by weight, and an acid source and an alkali source wherein said acid source and alkali source are capable of reacting together in the presence of water.
DETAILED DESCRIPTION OF THE INVENTION
The detergent composition of the present invention comprises four essential ingredients: anionic surfactant, cationic surfactant, an acid source and an alkali source. These and optional ingredients, and processes for making the detergents, are described in detail below.
Detergent Surfactants
The detergent composition can comprise one or more anionic surfactants, as described below, and one or more cationic surfactants.
Optionally, additional surfactants, selected from the group consisting of additional anionic and cationic surfactants, nonionic, zwitterionic, ampholytic and amphoteric surfactants can be present.
The total amount of surfactants is preferably of from 1% to 90%, preferably 3% to 70%, more preferably 5% to 40%, even more preferably 10% to 30%, most preferably 12% to 25% by weight of the detergent composition.
A preferred aspect of the present invention is a granular detergent composition. One or more of the surfactants can be comprised in a base composition, containing preferably also a builder material. The base composition may be prepared by spray-drying and dry-mixing/agglomeration. The base composition may also comprise some or all of the alkali source. Alternatively the acid source and/or alkali source may be added as separate components to the detergent base composition, preferably in a granular form.
Anionic Surfactant
The detergent composition of the present invention comprises one or more anionic surfactants. Any anionic surfactant useful for detersive purposes are suitable. Examples include salts (including, for example, sodium, potassium, ammonium, and substituted ammonium salts such as mono-, di- and triethanolamine salts) of the anionic sulfate, sulfonate, carboxylate and sarcosinate surfactants. Anionic sulfate surfactants are preferred.
Other anionic surfactants include the isethionates such as the acyl isethionates, N-acyl taurates, fatty acid amides of methyl tauride, alkyl succinates and sulfosuccinates, monoesters of sulfosuccinate (especially saturated and unsaturated C
12
-C
18
monoesters) diesters of sulfosuccinate (especially saturated and unsaturated C
6
-C
14
diesters), N-acyl sarcosinates. Resin acids and hydrogenated resin acids are also suitable, such as rosin, hydrogenated rosin, and resin acids and hydrogenated resin acids present in or derived from tallow oil.
The anionic surfactant is present at a level of 0.5% to 60%, preferably at a level of from 3% to 50%, more preferably of from 5% to 35%, most preferably from 65 to 20% by weight of the composition.
The ratio of the anionic surfactant to the cationic surfactant is preferably from 25:1 to 1:3, more preferably from 15:1 to 1:1. most preferably from 10:1 to 1:1.
Anionic Sulfate Surfactant
Anionic sulfate surfactants suitable for use herein include the linear and branched primary and secondary alkyl sulfates, alkyl ethoxysulfates, fatty oleoyl glycerol sulfates, alkyl phenol ethylene oxide ether sulfates, the C
5
-C
17
acyl-N—(C
1
-C
4
alkyl) and —N—(C
1
-C
2
hydroxyalkyl) glucamine sulfates, and sulfates of alkylpolysaccharides such as the sulfates of alkylpolyglucoside (the nonionic nonsulfated compounds being described herein).
Alkyl sulfate surfactants are preferably selected from the linear and br
Askew Stuart Clive
Sorrie Graham Alexander
Boyer Charles
Dressman Marianne
Gupta Yogendra
Miller Steven W.
The Procter & Gamble & Company
LandOfFree
Detergent composition having effervescent generating... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Detergent composition having effervescent generating..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detergent composition having effervescent generating... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2587992