JPS6138239B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel concentrated aqueous surfactant compositions containing mixtures of different surfactants for use in aqueous systems.

Mixtures of surfactants are manufactured and commercially available for a variety of industrial and domestic uses. These are often required to be in fluid form, and it is desirable that the concentration of active substance be as high as possible to save costs in terms of storage and transportation.

If the melting point of the mixture of surfactants is below or slightly above ambient temperature, the composition may optionally be provided in the form of an anhydrous mixture or with a water content of about 5% or less, respectively. It is possible to do so. In the latter case, trace amounts of water act as melting point depressants. Some surfactant compositions used primarily in non-aqueous systems form fluid mixtures containing trace amounts of water. Such compositions are only slightly soluble in aqueous systems at concentrations of about 2-5%.

However, for surfactant mixtures that are suitable for use in aqueous systems at active concentrations of 5-30% by weight and are solid at temperatures above about 25°C, approximately 30-50% by weight depending on the nature of the mixture. % active ingredient concentration was not possible. Approximately 10%
A small amount of water will not lower the melting point sufficiently, whereas a large amount of water that causes a phase change will result in the formation of a gel that is harder than a fluid solution. Generally, the total concentration of active ingredient in a dilute solution is
As a certain critical value is approached (usually about 30% by weight, but higher in some mixtures up to about 55% by weight), the viscosity of the solution begins to increase and the solution preparation and It becomes difficult to handle. At critical values, the solution forms an immobile gel or phase separation.

In some cases it is possible to increase the concentration of the active ingredient by adding co-solvents or viscosity modifiers, such as alcohols that act as thinners, to reduce the viscosity of the solution and inhibit the formation of gels; Higher concentrations can thereby be obtained. Although such co-solvents are effective in increasing the concentration of active ingredients added, their presence in large quantities can pose a fire hazard, adversely affect product properties, and increase product cost.

Some surfactant compounds have been reported to form highly viscous and non-injectable liquid crystal phases (e.g. “Advances in Colloid Interface”).
Science” 1, 1976, 79-110, pp. 82-83).
Some of these compounds, commonly referred to as "G-phases" or "lamellar phases," have relatively low viscosities when compared to other liquid-crystalline phases that form only within certain concentration ranges. form a phase. However, in the case of most industrially interesting compounds for which the existence of a "G phase" has been reported, the "G phase"
formed only at high temperatures. For example, in the case of sodium lauryl sulfate, an injectable "G phase" is reported to form at about 74°C. However, because such high temperatures are required, this phenomenon has hitherto been of purely academic interest and has not been used industrially. Furthermore, it has not been previously reported that a mixture of various surfactants forms a "G phase."

The inventors have recently discovered that certain surfactants of commercial value, such as certain ammonium alkyl sulfates and certain olefin sulfonates, form a "G phase" at ambient temperatures. This discovery has enabled the inventors to prepare these surfactants in fluid form at much higher concentrations than previously possible (see, for example, GB Patent Application No. 2038/74).

The inventors have discovered that certain mixtures of surfactants form a fluid lamellar (G) phase within a narrow range of concentrations above those that form a stationary phase. This concentration range is often 60-80%.

This mixture forms a fluid G phase at a temperature relatively lower than the minimum temperature at which an aqueous solution of each surfactant forms a G phase. Typically, this mixture forms a fluid G phase at ambient or slightly higher temperatures.

By preparing a solution of such a mixture at a specific concentration that forms a "G phase", it is possible to pump the active ingredient at a concentration that is, in some cases, more than twice the highest concentration of the conventional case. Surfactant mixtures can be obtained. This results in considerable savings in product transport and storage costs. Furthermore, it has been discovered that the highly active compositions of the present invention have bacteriostatic properties.

It is generally surprising that the compositions of the present invention can be readily diluted to conventional dilute concentrations and often tend to form intermediate gel phases when sufficient water is added to effectuate such dilution. There are almost no

The present invention provides an aqueous surfactant composition comprising water and an active ingredient mixture that can be diluted to an active ingredient concentration of 5 to 30% by weight; Surfactant Active Ingredient Mixture Comprising 40-80% by weight of at least 10% by weight of said active ingredient mixture being at least one zwitterionic surfactant; Anionic surfactants with a total surfactant concentration corresponding to the M ₁ /G phase boundary concentration of the active ingredient mixture, optionally containing one or more optional nonionic surfactants. higher than the total surfactant concentration, G
The aqueous surfactant composition of the present invention consists essentially of an aqueous surfactant composition that is lower than the total surfactant concentration corresponding to the phase/solid boundary concentration; ing.

The "G phase" is a pumpable phase formed in a narrow range of active ingredient concentrations, typically 40-80% by weight, in which surfactant molecules associate and are separated by planes of water molecules. It is characterized by a lamellar structure consisting of plate-like objects of indeterminate size.

When a surfactant mixture having the active ingredient composition of the present invention is prepared as an aqueous solution with increasing concentration, its molecules first associate as spherical groups (micelles),
As the concentration increases, it becomes rod-shaped. As the concentration increases, the micelles cluster further and increase the viscosity of the solution, often eventually forming regular hexagonal formations of cylindrical surfactant micelles in the aqueous medium (hard “M ₁ ” liquid crystal phase). As the concentration of the surfactant in the "M ₁ phase" increases further, the M 1 phase either forms a hydrated solid phase or, as in the case of the surfactants of the present invention, the M ₁ phase continues until a minimum viscosity is reached. Gradually converts to fluidity "G phase". When the concentration of "G phase" is further increased, the viscosity increases until a further phase change occurs. This in turn leads to the formation of a hydrated solid or a second immobile liquid crystal phase _{( M2} phase), which in its structure is similar to the _M1 phase, but the phase is reversed and Water becomes the discontinuous internal phase and surfactant becomes the continuous phase.

The term "hydrated solid phase" includes a suspension of a solid or immobile gel phase in one or more viscous or gel phases, which typically exhibits a granular appearance when examined under a polarized light microscope. It broadly refers to a system that consists of a hard substance that is hard.

Until now, no surfactants have been discovered that form liquid crystal phases, but mixtures of surfactants of the type identified here either have individual components that do not form a "G phase" or only form a "G phase" at high temperatures. Even if the mixture does not form a "G phase", it forms a fluid "G phase" as a mixture.

The inventors have discovered that, in general, the quantitative ratio of the active ingredient mixture required to form the "G phase" is determined according to the following formula:

c ₁ /g ₁ +c ₂ /g ₂ +...c _o /g _o = 1 In the above formula, c ₁ ... c _o is the concentration of each active ingredient, and g ₁ ... g _o is the concentration of each ingredient. lowest viscosity G
This is the concentration when forming a phase. In most cases, the concentration range of the mixture that forms the lowest viscosity "G phase" can be predicted by this equation. If the value of g is unknown, or for a component that does not form a G phase, or the above formula is not available, use standard laboratory equipment to calculate, for example, 75% (or approximately One can very quickly and easily obtain the desired active ingredient concentration range by preparing a sample of the test composition at an active ingredient concentration of the expected value and testing the sample by placing it on a heated microscope slide. can be detected. By examining crossed polarizers, the phase of the sample can be determined. Each of the different phases has a unique appearance;
Rosevear's JAOCS (Vol.31, P628, 1954) or J.Colloid and Interfacial Science (Vol.30,
It can be easily identified by comparing it with the photos of typical liquid crystal phases in the classification table of No. 4, P500).

If the mixture is in _M1 phase, the phase change can be observed by allowing water to evaporate from the edge of the sample in a capped sample plate. If the mixture is _M2 phase or hydrated solid,
Water is added around the edges in a sample plate with a lid and allowed to diffuse into the sample composition. If the "G phase" cannot be determined in this manner, the sample may be gradually heated on a microscope stage and the operation repeated.

Typically, the composition of the present invention has a minimum viscosity concentration of ±10%,
Preferably, a concentration range of ±5%, for example ±2.5%, can be pumped. This concentration range tends to become wider as the temperature increases. The desired composition is obtained in a concentration range in which one or more solid or gel phases are suspended in a continuous "G phase." Such compositions are useful for their appearance characteristics and are a feature of the present invention.

Typically, the compositions of the invention will contain two, three or four surfactants, with the concentration of each component being greater than 10% by weight of the total composition.

The compositions of the invention may also contain small amounts of non-surfactant organic solvents such as glycols or fatty alcohols and non-colloidal electrolytes such as sodium chloride or sodium sulfate. However, such components exist as impurities in the surfactant, and it is preferable not to add much solvent to the composition of the present invention. The amount of non-surfactant organic solvent is 5% by weight of the active ingredient mixture.
A smaller amount, preferably 5% by weight of the total composition
It is preferable to keep the amount smaller. More preferably the amount of solvent is kept below 2% by weight of the total composition, most preferably below 1%. The presence of inorganic salts or similar non-colloidal electrolytes is generally less harmful than the presence of organic solvents, but is generally undesirable because it tends to increase the viscosity of the fluid "G phase". Therefore, it is generally preferred to keep the amount of non-colloidal electrolyte similar to that mentioned for the organic solvent. However, in some cases the presence of certain electrolytes may be useful. For example, if the melting point of the G phase is slightly above ambient temperature, the addition of an electrolyte can lower the melting point so that the G phase is pumpable without heating. In such cases, it may be desirable to add up to about 6% by weight of an electrolyte such as sodium chloride or sodium sulfate.

The compositions of the invention may optionally contain surfactants other than those specified above in small amounts, for example in amounts of 5% or more by weight of the active ingredient mixture.

The active ingredient mixture in the compositions of the invention includes at least one zwitterionic surfactant. An example of this zwitterionic surfactant is betaine, e.g. (Each R is an alkyl, cycloalkyl, alkenyl or alkaryl group, preferably at least one and most preferably no more than one R group having an average of 8 to 20, such as 10 to 18 aliphatic There are betaines having carbon atoms (each other R group having on average 1 to 4 carbon atoms). Particularly preferred is the following formula (R and R ¹ are alkyl, alkenyl, cycloalkyl, alkaryl or alkanol groups having on average 1 to 20 aliphatic carbon atoms, R preferably having from 8 to 20, for example 10 to 18 aliphatic carbon atoms) R ¹ preferably has 1 to 4 carbon atoms). Examples of other zwitterionic surfactants used in accordance with the invention include alkylamine ether sulfates, sulfobetaines and other quaternary amines or quaternized imidazoline sulfonic acids and their salts, and other Quaternary amines or quaternized imidazoline carboxylic acids and their salts, and zwitterionic surfactants such as N-alkyltaurine, carboxylated amidoamines, e.g.
RCONH( _{CH2 ) 2N} ( _CH2CH2CH ) _CH2CO2 and hydrocarbon groups capable of imparting surface-active properties (e.g. alkyl _, cycloalkyl, alkenyl with 8 to 20 aliphatic carbon atoms) or an alkaryl group). Representative examples include 2-talo-alkyl 1-talo-amidoalkyl 1-carboxymethylimidazoline and 2-coconutalkyl N-carboxymethyl 2-(hydroxyalkyl)imidazoline. In general, any water-soluble zwitterionic surfactant compound having a hydrophobic moiety such as a _C8-20 alkyl or alkenyl group and a hydrophilic moiety such as an amine or quaternary ammonium group and a carboxylate, sulfate or sulfonic acid group. However, it can be used in the present invention.

Examples of anionic surfactant components include alkyl sulfates, alkyl ether sulfates, alkylbenzene sulfonates, olefin sulfonates, paraffin sulfonates,
sulfosuccinate, sulfosuccinate,
Taurides or sarcosinates, soaps, alkyl phenyl sulfates, alkyl phenyl ether sulfates or alkyl phenyl ether sulfonates, fatty acid sulfonates or fatty acid ester sulfonates, or alkyl phosphates or alkyl ether phosphates; Each of these has a total of 8 to 20
, preferably 10 to 18 carbon atoms. Among the above descriptions, the term "ether" is 1 to 30.
, preferably 1 to 10 oxyethylene and/or
or a polyoxyalkylene group formed from an oxypropylene group and/or a glycerin group.

Amphoteric surfactants and anionic surfactants each represent at least 10% by weight of the active ingredient mixture, preferably at least 20%, most preferably at least 30%, such as at least 40%. The zwitterionic surfactant and anionic surfactant are preferably present in substantially equal molar ratios. For example, each constitutes 50% of the active ingredient mixture. Examples of cations of anionic surfactants include alkali metals such as sodium, potassium or lithium, ammonium or substituted ammonium, such as primary, secondary, tertiary or quaternary alkylammonium or alkylolammonium ions, or dissolved As long as nature allows, there are alkaline earth metals such as calcium.

Examples of nonionic surfactants which are optional components that may be included in the composition of the present invention include ethoxylated fatty alcohols, ethoxylated fatty acids, ethoxylated alkylphenols, ethoxylated glycerol, or sorbitan fats. There are group esters. Examples of other nonionic surfactants include alkylolamides, ethoxylated alkylolamides and amine oxides.

8 to 20 of each nonionic surfactant,
Preferably it has an alkyl group having 10 to 18 carbon atoms. Non-ionic surfactants preferably account for up to 50% by weight in the active ingredient mixture, preferably
Less than 30% by weight, most preferably 20% by weight
Present in lesser amounts, for example less than 10% by weight.

The PH of the composition is usually 5-10. Depending on the chemical nature of the zwitterionic surfactant, the fluidity “G phase”
is within a certain PH range, usually PH 7-9, for example around 8
The above results are obtained. If the PH is low enough to protonate the acid groups of the zwitterionic surfactant, there will be a tendency to convert the "G phase" into various phases, such as opaque emulsions. These emulsions are stable and injectable;
Contains a mixture of active ingredients in a concentration range corresponding to the "G phase". These are therefore useful products and constitute another feature of the invention.

The invention will be explained in more detail by the following examples.

Example 1 1 mole of 1-(hydroxyethyl)-2-cocoyl imidazolidine is mixed with 2.1 moles of chloroacetic acid and water in the presence of sufficient water to give a 23% by weight solution of the imidazoline starting material. It was heated at 55° C. for 12 hours with 4.1 mol of sodium oxide. PH is
It was adjusted to 8.5 with a 35% aqueous hydrochloric acid solution. PH is measured on a diluted solution of 10 parts solution and 90 parts water.

A composition was prepared containing 58.4% by weight of the quaternized imidazoline solution prepared as described above, 37.9% by weight of a 29% aqueous solution of sodium lauryl sulfate, and 3.7% by weight of 90% sodium lauryl sulfate. The product was a free-flowing, translucent composition that upon microscopic examination was found to be "G-phase."

Example 2 One mole of 1-(hydroxyethyl)-2-laurylimidazolidine is mixed with 2.5 moles of chloroacetic acid and sodium hydroxide in the presence of sufficient water to give a 20% solution of the imidazoline starting material. 4.8
mol and reacted at 55°C for 12 hours.

A composition was prepared containing 67% of the resulting quaternized imidazoline solution and 33% of a 70% aqueous solution of sodium lauryl 3 molar ethylene oxysulfate. The product was a free-flowing, translucent composition that upon microscopic examination was found to be "G-phase."

Example 3 29.9 g of a 70.6% solution of C _12-14 sodium alkyl 3 mole ethoxylated sulfate and C _8-13 amidoamine betaine 70.1 g of a 30% solution of were mixed together.

This mixture contained equal parts by weight of anionic surfactant and amphoteric surfactant, and the total surfactant concentration was 42.1%. The product was found to be a viscous gel with M ₁ phase.

This sample was heated on a steam bath in a stream of air to evaporate the water, resulting in an overall concentration of surfactant of 73.8%.
The concentrated mixture was a free-flowing, translucent composition that upon microscopic examination was found to be in "G phase."

The composition of this mixture was as follows.

Sodium alkyl 3 mole ethoxylated sulfate 37% Amidoamine betaine 37% Sodium chloride 9% Other impurities 2-3% Water Remaining example 4 46 g of a 70.6% solution of C _12-14 sodium alkyl 3 mole ethoxylated sulfate and C _8-18 amidoamine betaine 54 g of a 30% solution of were mixed together. This mixture contained 2 parts by weight of anionic surfactant per 1 part by weight of zwitterionic surfactant, giving a total surfactant concentration of 48.7%. The product was found to be a viscous gel with M ₁ phase.

The sample was heated on a steam bath in a stream of air to evaporate the water, giving a total surfactant concentration of 64.6%. This concentrated mixture is a free-flowing, translucent composition, and microscopically shows "G phase".
I found out that it is.

The composition of this mixture was as follows.

Sodium alkyl 3 mole ethoxylated sulfate 43% Amidoamine betaine 21.5% Sodium chloride 5.5% Other impurities 2-3% Water Remaining example 5 29.9 g of a 70.6% solution of C _12-14 sodium alkyl 3 mole ethoxylated sulfate and C _12-14 alkyl dimethyl 70.1 g of a 30% solution of amine betaine were mixed together. This mixture contained equal parts by weight of anionic surfactant and amphoteric surfactant, with a total surfactant concentration of 42.1%. The product was found to be a viscous gel, with M ₁ phase.

The sample was heated on a steam bath in a stream of air to evaporate the water and give a total surfactant concentration of 59.4%. This concentrated mixture was a free-flowing, translucent composition that upon microscopic examination was found to be "G-phase."

The composition of this mixture was as follows.

Sodium alkyl 3 mole ethoxylated sulfate 30% Alkyldimethylamine betaine 30% Sodium chloride 7.5% Other impurities 2-3% Water Remaining example 6 28.9 g of a 71.1% solution of monoethanolamine salt of C _12-14 alkyl sulfate and C ₁₂ 70.2 g of a 30% solution of _~14 alkyldimethylamine betaine (previously treated to remove sodium chloride by electrodialysis) were mixed together.

The mixture was a free-flowing, translucent composition that upon microscopic examination was found to be "G-phase."

The composition of this mixture was as follows.

Monoethanolamine salts of alkyl sulfates
21% Alkyldimethylamine betaine 21% Other impurities 2-3% Water Remaining example 7 46.9% solution of dioctyl sulfosuccinate
39 g and 61 g of a 30% solution of _C12-14 alkyldimethylamine betaine (previously treated to remove sodium chloride by electrodialysis) were mixed together. This mixture contained equal parts by weight of anionic surfactant and zwitterionic surfactant, with a total surfactant concentration of 36.6%. This sample was a viscous gel and was found to be in the _M1 phase.

The sample was heated on a steam bath in a stream of air to evaporate the water and give a total surfactant concentration of 62.7%. This concentrated mixture is a free-flowing, translucent composition that, when examined microscopically, is labeled as
It turned out that it was "Ai".

The composition of this mixture was as follows.

Alkyldimethylamine betaine 31.5% Dioctylsulfosuccinate (Na salt)
31.5% Dioctyl maleade 5% Other impurities 1% Water Remaining example 8 29.9 g of a 70.6% solution of C _12-14 sodium alkyl 3 mole ethoxylated sulfate and C _8-10 amidoamine 70.1 g of a 30% solution of are mixed together, this mixture is
Contained 2.5% glycerol. This mixture contained equal parts by weight of anionic surfactant and zwitterionic surfactant, with a total surfactant concentration of 42.1%. This substance is a viscous gel
It was found to be _M1 phase.

The sample was heated on a steam bath in a stream of air to evaporate the water and give a total surfactant concentration of 67%. The concentrated mixture was a free-flowing, translucent composition that upon microscopic examination was found to be in Phase G.

The composition of this mixture was as follows.

Sodium alkyl 3 mole ethoxylated sulfate 33.5% Amidoamine betaine 33.5% Sodium chloride 8.5% Chrycerol 3.0% Other impurities 2-3% Water Remaining example 9 46.9% solution of dioctyl sulfosuccinate
39g and C _8-18 amidoamine 61 g of a 30% solution of were mixed together. This mixture contained equal parts by weight of anionic surfactant and zwitterionic surfactant, with a total surfactant concentration of 36.6%. This material was found to be a viscous gel and to be in the _M1 phase.

The sample was heated on a steam bath in a stream of air to evaporate the water and give a total surfactant concentration of 61%. The concentrated mixture was a free-flowing, translucent liquid that upon microscopic examination was found to be in phase G.

The composition of this mixture was as follows.

Amidoamine Betaine 30.5% Dioctylsulfosuccinate (Na salt)
30.5% Dioctyl maleate 5% Sodium chloride 7.5% Other impurities 1% Water remaining

Claims (1)

[Claims] 1. An aqueous surfactant composition consisting of 40 to 80% by weight of water and a surfactant active ingredient mixture, said active ingredient mixture comprising at least 10% of the active ingredient mixture.
% by weight of at least one zwitterionic surfactant, at least 10% by weight of the active ingredient mixture of at least one anionic surfactant, and 0 of one or more optional nonionic surfactants. ~
80% by weight, the active ingredient mixture is capable of forming a G phase in the presence of water, and at least a major proportion of the composition is present in the G phase, and the composition is non-surfactant. An aqueous surfactant composition, preferably substantially free of organic solvents and added non-colloidal electrolytes.