EP0430330A2

EP0430330A2 - Suspending liquid detergent compositions

Info

Publication number: EP0430330A2
Application number: EP90203017A
Authority: EP
Inventors: Francesco De Buzzaccarini
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1989-11-24
Filing date: 1990-11-14
Publication date: 1991-06-05
Also published as: NZ236205A; MX172443B; PE31191A1; TR25074A; AR245207A1; AU650247B2; JPH03210400A; AU6695690A; EP0430330A3; BR9005930A; IE904243A1; CA2030205C; CA2030205A1

Abstract

Pourable aqueous detergent compositions containing C₁₀-C₁₆ alk(en)yk substituted succinic acid as a builder, are formulated as neat phases.

Description

Technical Field

The invention relates to aqueous built detergent compositions which are pourable, and have suspending properties.

Background

Aqueous pourable detergent compositions are well known in the Art, but it is only recently that C₁₀-C₁₆ alk(en)yl substituted succinic acids have been used as builders in these compositions, which have been disclosed in EP-A-0 293 040 and EPA- 0 294 904.
These compositions are very satisfactory in terms of their cleaning performance, but ingredients in the form of solid particles could not be stably suspended in these compositions, and therefore it is recommended to use only liquid ingredients during their manufacture. Indeed, the use of ingredients in the form of solid particles inevitably leads to sedimentation.
Pourable compositions having such suspending properties have been disclosed for instance in EP-A -0 151 884, EP-A-0 120 638, EP-A-0 092 363, GB-A-2 023 637, US-A-4 692 271; all the compositions disclosed in these documents do not contain C₁₀-C₁₆ alk(en)yl substituted succinic acids, and it has been found that said compositions would lose their suspending properties upon incorporation of said substituted succinic acids.
It is an object of the present invention to provide aqueous, pourable detergent compositions, which contain C₁₀-C₁₆ alk(en)yl substituted succinic acids and which further have suspending properties.
Further, the compositions of the prior art tend to collapse also if hydrophilic solvents are incorporated in important amounts; it is another object of the present invention to provide aqueous, pourable detergent compositions, which contain C₁₀-C₁₆ alk(en)yl substituted succinic acids and have suspending properties, and which may further contain hydrophilic solvents, such as ethanol.

Summary

It has now been found that aqueous, pourable detergent composition containing an anionic surfactant and C₁₀-C₁₆ alk(en)yl substituted succinic acid could acquire suspending properties by formulating them as neat phases, by incorporating at least 7.5% by weight of the total composition of a compound of the formula
RO(CH₂CH₂O)_yH
wherein:
-R is a C_n alkyl, alkenyl, alkynyl, aryl or alkyl aryl group
-and n is an integer of from 4 to 22
-and y = 0 to 4
-and n/y ≧ 2 if y
0

Detailed Description of the Invention

The present invention addresses the problem of formulating an aqueous detergent composition which contains C₁₀-C₁₆ alk(en)yl substituted succinic acids, and which has suspending properties.
It has been found that such composition can be formulated as a neat phase as follows. In the following, the expression neat phase (or G-phase) refers to an essentially lamella-structured or spherulitic composition in which aqueous layers are separated by double layers of hydrophobic materials.
Such a lamellar structure can be identified by observing the product through an optical microscope, between crossed Nichol prisms.
The neat phases are characterized by specific textures which are described for instance by F.B. Rosevear, journal of the American Oil Chemists Society, vol. 3, page 628, 1954.
The compositions of the invention always contains an anionic surfactant.
Suitable anionic surfactants can be represented by the general formula R¹SO³M wherein R¹ represents a hydrocarbon group selected from the group consisting of straight or branched alkyl radicals containing from about 8 to about 24 carbon atoms and alkyl phenyl radicals containing from about 9 to about 15 carbon atoms in the alkyl group. M is a salt forming cation which typically is selected from the group consisting of sodium, potassium, ammonium, and mixtures thereof.
A preferred synthetic anionic surfactant is a water-soluble salt of an alkylbenzene sulfonic acid containing from 9 to 15 carbon atoms in the alkyl group. Another preferred synthetic anionic surfactant is a water-soluble salt of an alkyl sulfate or an alkyl polyethoxylate ether sulfate wherein the alkyl group contains from about 8 to 24, preferably from about 10 to about 18 carbon atoms and there are from about 1 to about 20, preferably from about 1 to about 12 ethoxy groups. Other suitable anionic surfactants are disclosed in US Patent 4,170,565, Flesher et al., issued October 9, 1979.
Suitable anionic synthetic surface-active salts are selected from the group of sulfonates and sulfates. Preferred anionic synthetic water-soluble sulfonate or sulfate salts have in their molecular structure an alkyl radical containing from about 8 to about 22 carbon atoms.
Exemples of such preferred anionic surfactant salts are the reaction products obtained by sulfating C₈-C₁₈ fatty alcohols derived from tallow and coconut oil; alkylbenzene sulfonates wherein the alkyl group contains from about 9 to 15 carbon atoms; sodium alkylglyceryl ether sulfonates; ether sulfates of fatty alcohols derived from tallow and coconut oils; coconut fatty acid monoglyceride sulfates and sulfonates; and water-soluble salts of paraffin sulfonates having from about 8 to about 22 carbon atoms in the alkyl chain. Sulfonated olefin surfactants as more fully described in e.g. US Patent Specification 3,332,880 can also be used. The neutralizing cation for the anionic synthetic sulfonates and/or sulfates is represented by conventional cations which are widely used in detergent technology such as sodium and potassium.
A particularly preferred anionic synthetic surfactant component herein is represented by the water-soluble salts of an alkylbenzene sulfonic acid, preferably sodium alkylbenzene sulfonates having from about 10 to 13 carbon atoms in the alkyl group.
The compositions of the invention may additionally contain zwitterionic surfactants which include derivatives of aliphatic quaternary ammonium, phosphonium, and sulphonium compounds in which the aliphatic moiety can be straight or branched chain and wherein one of the aliphatic substituents contains from about 8 to about 24 carbon atoms and another substituent contains, at least, an anionic water-solubilizing group. Particularly preferred zwitterionic materials are the ethoxylated ammonium sulfonates and sulfates disclosed in US Patents 3,925,262, Laughlin et al., issued December 9, 1975 and 3,929,678, Laughlin et al., issued December 30, 1975.
The compositions may also contain small amounts, i.e. below 1% by weight of the total composition, of cationic surfactants. Examples of suitable cationic surfactants include quaternary ammonium compounds of the formula R₁R₂R₃R₄N⁺X⁻, wherein R₁ is C₁₂-C₂₀ alkyl or hydroxyalkyl; R₂ is C₁-C₄ alkyl or C₁₂-C₂₀ alkyl or hydroxyalkyl or C₁-C₄ hydroxyalkyl; R₃ and R₄ are each C₁-C₄ alkyl or hydroxyalkyl, or C₆-C₈ aryl or alkylaryl; and X⁻ is halogen. Preferred are mono-long chain quaternary ammonium compounds (i. e., compounds of the above formula wherein R₂ is C₁-C₄ alkyl or hydroxyalkyl).
The total amount of surfactant in the compositions is of from 5% to 60%, preferably 15% to 40% by weight of the total composition.
The compositions of the invention additionally contain at least 7,5% of a compound of the formula
RO(CH₂CH₂O)_yH
wherein
- R is a C_n alkyl, alkenyl, alkynyl, aryl or alkyl aryl group
- n is an integer of from 4 to 22
- y = 0 to 4
- and n/y ≧ 2 if y
0
or mixtures thereof.
Preferred compounds according to this definition are condensation products of ethylene oxide with a fatty alcohol in the presence of an acidic or basic catalyst.
Preferably, fatty alcohols having from 13 to 15 carbon atoms are used to make such condensation product.
Also preferred are such solvents as butanol, butoxyethanol, benzylalcohol, hexyl diglycol ether, butyl diglycolether, and mixtures thereof.
The compounds are present in the compositions of the invention in an amount of at least 7,5% by weight of the total composition, preferably from 8% to 15% by weight.
The compositions of the invention also contain as a builder system, from 5% to 20% by weight of the total composition of a C₁₀-C₁₆ alk(en)yl substituted succinic acid, preferably from 8% to 15% by weight of the total composition. The preferred builder for use herein is dodecenyl substituted succinic acid.
Importantly, the compositions of the invention contain water, in an amount of from 20% tp 60% by weight of the composition.
All the hereinbefore mentioned ingredients are mixed together so as to obtain a compositon which is structured as a neat phase.
Optionally, the compositions of the invention may contain an electrolyte such as sodium bromide, chloride, iodide, nitrate or acetate, preferably sodium chloride.
Other optionals include detergent enzymes. Suitable enzymes include the detergent proteases, amylases, lipases and cellulases. Enzymatic stabilizing agents for use in aqueous liquid detergents which are well known, can also be used herein; preferred is a salt of formic acid, e.g., sodium formate. The amount of this stabilizing agent typically ranges from 0.5% to 2%.
Examples of organic builders are represented by polyacids such as citric acid, nitrilotriacetic acid, and mixtures of tartrate monosuccinate with tartrate disuccinate. Preferred builders for use herein are citric acid. Polymeric carboxylate builders inclusive of polyacrylates, polydydroxy acrylates and polyacrylates/polymaleates copolymers can also be used.
The compositions of the invention may also contain chelants, such as ethylenediaminotetracetic acid, diethylenetriaminopentacetic acid, ethylenediamino disuccinic acid or the water-soluble alkali metals thereof. Other additives include organo-phosphonic acids; particularly preferred are ethylenediamino tetramethylenephosphonic acid, hexamethylenediamino tetramethylenephosphonic acid, diethylenetriamino pentamethylenephosphonic acid, aminotrimethylenephosphonic acid and hydroxyethylidene 1,1 diphosphonic acid.
The compositions herein can contain further optional ingredients which are mostly used in additive levels, usually below about 5%. Examples of the like additives include : Suds regulants, opacifiers, agents to improve the machine compatibility in relation to enamel-coated surfaces, bactericides, dyes, perfumes, brighteners and the like.
The beneficial utilization of the claimed compositions under various usage conditions can require the utilization of a suds regulant like polysiloxanes such as dimethylpolysiloxane, also frequently termed silicones. These silicones are frequently used in a level not exceeding 1.5%, most preferably between 0.1% and 1.0%.
It can also be desirable to utilize opacifiers inasmuch as they contribute to create a uniform appearance of the concentrated liquid detergent compositions. Examples of suitable opacifiers include : polystyrene commercially known as LYTRON 621 manufactured by MONSANTO CHEMICAL CORPORATION. The opacifiers are frequently used in an amount from 0.3% to 1.5%.
It can further be desirable to add from 0.1% to 5% of known antiredeposition and/or compatibilizing agents. Examples of the like additives include : sodium carboxymethylcellulose; hydroxy-C₁₋₆-alkylcellulose; polycarboxylic homo- or copolymeric ingredients, such as : polymaleic acid; a copolymer of maleic anhydride and methylvinylether in a molar ratio of 2:1 to 1:2; and a copolymer of an ethylenically unsaturated monocarboxylic acid monomer, having not more than 5, preferably 3 or 4 carbon atoms, for example (meth)acrylic acid, and an ethylenically unsaturated dicarboxylic acid monomer having not more than 6, preferably 4 carbon atoms, whereby the molar ratio of the monomers is in the range from 1:4 to 4:1, said copolymer being described in more detail in EUROPEAN Patent Application 0 066 915, filed May 17, 1982.
Since the compositions of the invention have acquired suspending properties, due to the formulation as a neat phase, it is possible to use ingredients which are in the form of solid particles. There is no restriction as to the nature of the ingredient, but these ingredients are preferably in the form of solid particles having an average diameter size in the range of from 1 micrometer to 350 micrometers.
Such ingredients can be zeolites, clays, suds suppressors such as silica waxes, any encapsulated material, and a highly preferred ingredient to be suspended in the compositions are solid, water-soluble peroxygen bleaching compounds, preferably perborates, persulfates, peroxydisulfates, perphosphates and the crystalline peroxyhydrates formed by reacting hydrogen peroxide with sodium carbonate or urea. Preferred are sodium perborate, monohydrate and tetrahydrate, and sodium percarbonate.
If a peroxygen bleaching compound is used, the compositions preferably contain water miscible organic solvents including ethanol, n-propanol, isopropanol polyethylene glycol, dipropylene glycol, hexylene glycol, methoxyethanol, ethoxyethanol, ethyldiglycolether, and mixtures thereof. Preferably, the compositions will contain from 4% to 10% of the total composition of ethanol, as a stabilizing system for the peroxygen compounds.
Also, in such a case, the pH as is of the compositions should be in the range of from 8 to 12, preferably 9 to 11.
The following examples will illustrate and facilitate the understanding of the invention, but are not meant to restrict its scope.

Examples

The following composition are obtained by mixing together the listed ingredients in the listed proportions.
The order in which the ingredients are mixed plays no role in the achievement of the neat phase structure; it is however particularly convenient to proceed as follows, referring to example IV.
A premix which is made with water, diethylene triamine pentamethylene phosphonic acid and citric acid is neutralized to pH 7 with sodium hydroxide. The solvents (ethanol and hexyl diglycolether) are then added.The linear alkyl benzene sulfonate and the dodecenyl substituted succinic acid are added while cooling the mixture; the pH is then trimmed to 10 with sodium hydroxide. The composition at this point is not yet a neat phase, but an isotropic solution characterized by its low viscosity and transparency. The neat phase which is formed on adding the C₁₄alcohol 3 times ethoxylated can be identified by a higher viscosity and a translucent appearance; to confirm the formation of the neat phase structure, the composition can be examined with an optical microscope, between crossed Nichol prisms.
The sodium chloride and all minor ingredients are finally incorporated in the composition.
If an ingredient in the form of solid particles is to be incorporated, it is preferable to do so before the formation of the neat phase, in order to facilitate the mixing.

Claims

1. A detergent composition comprising a anionic surfactant, from 5% to 20% by weight of the total composition of a C₁₀-C₁₆ alk(en)yl substituted succinic acid, characterized in that it is formulated as a neat phase.

2. A detergent compositions according to claim 1, characterized in that it comprises at least 7.5% by weight of the total composition of a compound of the formula
RO(CH₂CH₂O)_yH wherein :
- R is a C_n alkyl, alkenyl, alkynyl, aryl or alkyl aryl group
- and n is an integer of from 4 to 22
- and y = 0 to 4
- and n/y ≧ 2 if y

0
and mixtures thereof.

3. A detergent composition according to claim 1 or 2, characterized in that it comprises from 6% to 15% by weight of the total composition of a C₁₀-C₁₆ alk(en)yl substituted succinic acid.

4. A detergent composition according to claims 2 or 3, wherein the compound is selected from butyl diglycol ether, hexyl diglycol ether and the condensation products of C₁₃-C₁₅ fatty alcohols with 3 moles of ethylene oxide per mole of fatty alcohol, or mixtures thereof.

5. A detergent composition according to claims 2, 3 or 4, wherein said compound is present in an amount of from 8% to 15% by weight of the total composition.

6. A detergent composition according to any of the preceding claims, characterized in that it contains up to 10% by weight of the total composition of an electrolyte.

7. A detergent composition according to claim 6 characterized in that the electrolyte is sodium chloride.

8. A detergent composition according to any of the preceding claims, characterized in that it contains at least one ingredient which is in the form of solid particles.

9. A detergent composition according to any of the preceding claims, characterized in that it contains a peroxygen compound.

10. A detergent composition according to claims 8 and 9 characterized in that the peroxygen compound is in the form of particles having a diameter size in the range of from 1 micrometer to 350 micrometer.

11. A detergent composition according to claim 9 or 10 characterized in that the peroxygen compound is a perborate.

12. A detergent composition according to claim 9 or 10 characterized in that the peroxygen compound is a percarbonate.

13. A detergent composition according to claims 8, 9 or 10 characterized in that it further comprises from 3% to 12% by weight of the total composition of ethanol.

14. A detergent composition according to claims 9 to 13, which has a pH of at least 9.