JPH06102795B2 - Liquid detergent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a surfactant structure within the composition.
liquid detergent composition comprising sufficient detergent active material and sufficient dissolved electrolyte to form a structure). Such compositions are not secondary additives such as some cross-linked polyacrylates that are added to the unstructured composition as "external structurants", but derive their structuring from the primary component. Therefore, it is sometimes said to be “internally structured”.

Internal structuring is well known to those of skill in the art and is intended to provide the consumer with flow characteristics and / or a hazy appearance. Many internally structured liquids can also suspend solid particles such as detergent builders and abrasive powders. An example of a structured liquid without suspended solids is shown in US Pat. No. 4,244,840, while a suspended example of solid granules is EP-A-1603.
42; EP-A-38101; EP-A-104452 and above-mentioned U.S. Pat. No. 4,244,840.

Various possible surfactant structuring (surfactant structurin
Some of g) are from K. Walters (ed.), “Rheometry: Industrial Use,” J. Wiley & Sons, Letchworth (1980).
Chapter 2, "Detergents" by HA Barnes. In general, the regularity of such systems increases with increasing concentration of surfactant and / or electrolyte. At very low concentrations, surfactants can exist as molecular solutions or spherical micelles (both isotropic). The addition of further surfactants and / or electrolytes forms a structured (anisotropic) system. These are referred to by various names such as rod-shaped micelles, plane lamella structure, lamella drop, and liquid crystal phase.
Others will often use other terms to refer to substantially the same structure. The presence of the surfactant structuring system in the liquid can be detected by means known to those skilled in the art, such as optical techniques, various flow measurements, X-ray or neutron diffraction, and optionally electron microscopy.

One well-known type of internal surfactant structure is called lamellar droplet dispersion (lamellar dispersion). Each lamellar droplet consists of concentric bilayers of surfactant molecules arranged in an onion, between which water or an electrolyte solution (aqueous phase) is entrapped. In systems such as densely packed lamellae droplets, the combination of physical stability, solids suspension, useful flow properties, etc. is highly desirable.

In the present specification, the term "electrolyte" means an ionic water-soluble substance. However, in the structured liquid, not all of the electrolyte is necessarily dissolved, but it may be suspended as solid particles. This is because the total electrolyte concentration of the liquid is higher than the electrolyte solubility limit. Mixtures of electrolytes may also be used, in which case one or more electrolytes may be in the dissolved aqueous layer, while the other one or more may only be present in the substantially suspended solids phase. Two or more electrolytes may be distributed between these two phases in approximately proportional proportions. In part this depends on the treatment, ie the order of addition of the components. The term "salt" refers to all organic and inorganic substances (compounding ingredients), with or without ionic properties, except surfactants and water, and this term is a subordinate concept of electrolytes (water-soluble substances). Also includes.

The amount and type of surfactants and salts (eg, builders, buffers, enzyme stabilizers, preservatives) that are ideally incorporated into such systems will vary widely depending on the type of formulation. Unfortunately, this can be hampered by the incompatibility of the ingredients. One is the salting-out (precipitation) of surfactants by the salts present. This is a problem when salting out depends on the properties of the substance in question, but when one or both of the salt concentration and the surfactant concentration are relatively high. This is often a problem (if not always) when the salt contains large amounts of electrolyte.

This has created a need to identify surfactants and surfactant mixtures that are stably incorporated in such liquids to allow improved broad tolerances in salt type and concentration. . This is basically a patent specification EP
-It is a problem addressed in A-178,006. But,
The surfactants (alkyl polycarboxylates) described in EP-A-178,006 do not provide the electrolyte tolerances that the present invention seeks to provide.

Since many useful salts are also electrolytes, a suitable surfactant that provides the required improvement is to dissolve it in water and test its tolerance by successively increasing the amount of electrolyte added. It can be confirmed. However,
We have found that this does not always work as expected.

The reason is that an aqueous solution of a surfactant is a molecular solution (molecu
lar solution) or spherical micelle solution. This is quite different from the arrangement of surfactant molecules in a structured liquid. Therefore, when electrolytes are sequentially added to a molecular or spherical micellar solution of a surfactant, the behavior of the surfactant does not necessarily mimic its behavior in a structured system.

However, unexpectedly, a particularly suitable surfactant (hereinafter referred to as "stabilizing surfacta
nt) ”) defines the appropriate thresholds to determine whether a particular surfactant will pass the test, and centrifuges the composition containing the stabilizing surfactant. Then under the condition that some kind of result is obtained,
It turned out that it can be confirmed by the above-mentioned general test. This advantageously allows selection of surfactants that can be used in the novel internal structured detergent liquid.

In the present specification, the test for electrolyte tolerance is referred to as salting-out resistance measurement. For this test, 200 ml of a 5% by weight aqueous solution of the surfactant in question are prepared. The trisodium salt of nitrolotriacetate (NTA) is added at room temperature (about 25 ° C) until turbidity and observable phase separation occurs. The amount of NTA added up to this point (NTA 1 mole is 3 equivalents) is the salting-out resistance of the surfactant. (This amount is expressed in gram equivalent of NTA added to 1 liter of the surfactant solution.) For convenience,
Use SOR as an abbreviation for salting out resistance.

The aqueous liquid detergent composition of the present invention contains a sufficient amount of detergent active material and dissolved electrolyte to cause surfactant structuring in the composition and is centrifuged at 750 G for 20 hours at 25 ° C. Does not form a substantially transparent liquid active layer, and the detergent active material is stable, having an average alkyl chain length of 6 or more carbon atoms and a salting-out resistance (defined above) of 6.4 or more. It is characterized by containing a chemical surfactant.

Compared to known surfactant structured liquid detergents, the choice of surfactants of the present invention provides considerable flexibility in that large amounts of salts, especially soluble salts (ie electrolytes) can be added to the compositions of the present invention. And also allows the addition of polymeric builders, especially water-soluble builders. This allows
The desired viscosity reduction of the product can also be realized. The addition of higher amounts of surfactant is beneficial for the removal of lipid soils. Especially when the stabilizing surfactant is non-ionic,
A larger amount of nonionic surfactant than anionic surfactant is added later, which is also advantageous for the stability of existing enzymes. Enzymes are generally more sensitive to anionic than nonionic systems. In general, in the present invention, it has been found that the larger the actual speed SOR, the lower the concentration of the surfactant required to exert a predetermined effect.

For the composition of the present invention, not only comprising at least some stabilizing surfactant as described above, but also at 25 ° C. for 20 hours,
It is necessary to prevent the formation of a substantially transparent liquid active rich layer even after centrifugation at 750G. The symbol G indicates the normal gravity value of the earth. This requirement excludes compositions that do not exhibit the effect of the composition of the present invention, and also filed at the same time as this application, entitled "Aqueous Detergent Composition and Method for Producing the Same", filed by the same applicant (c. The composition of interest in (1) is also excluded.

As used herein, the term "transparent" with respect to a liquid active layer means completely or substantially transparent to the naked eye. 10 liquid layers not active rich
It comprises less than 5% by weight, preferably less than 5% by weight, more preferably less than 2% by weight of surface-active (detergent active) substances.

The stabilizing surfactant may constitute all or part of the detergent active material. The only limitation on the total amount of detergent active material and electrolyte is that they must together form a structured system. Thus, within the scope of the present invention, very wide variations in the type and amount of surfactant are possible. The choice of surfactant type and loading is within the ability of one of ordinary skill in the art in light of the teachings of the present invention in obtaining a stable liquid having the desired structure. However, an important subclass of useful compositions is one in which the detergent active material comprises one or more stabilizing or surfactants together with one or more conventional or "primary" surfactants. But it could be. Typical blends useful in fabric cleaning compositions are those where the primary surfactant comprises nonionic and / or nonalkoxylated anions and / or alkoxylated anionic surfactants.

The stabilizing surfactant has an average alkyl chain length of 6 or more carbon atoms, and generally it is preferred that the stabilizing surfactant has an average alkyl chain length of 8 or more carbon atoms. Particularly preferred classes of stabilizing surfactants used alone or in combination are: alkyl polyalkoxylated phosphates; alkyl polyalkoxylated sulfosuccinates; dialkyl diphenyl oxide disulfonates and alkyl polysaccharides (alkyl polyglucosides or It is also called polyglycoside.). A variety of such stabilizing surfactants are known to those of skill in the art. For example EP-A-70074; 7007
5; 70076; 70077; 75994; 75995; 75996 and 92355.

Particularly preferred is a stabilizing surfactant having an SOR of 9.0 or more (regardless of chemical structure).

In many (but not all) cases, the total detergent active material may be present in the range of 2 to 50% by weight of the total composition, preferably 5 to 35% by weight, more preferably 10 to 30%. These figures apply both to blends of primary and stabilizing surfactants and where the detergent active material is all composed of stabilizing surfactants. However, in a blend of primary surfactant and stabilizing surfactant, the amount of stabilizing surfactant is typically 0.
It is 1 to 45% by weight, particularly 0.5 to 30% by weight, more preferably 1 to 30% by weight. In such blends, the stabilizing surfactant is 5 to 90% by weight of the total detergent active material, especially 7.
Often ranges from 5 to 90% by weight, most preferably 10 to 90% by weight.

In general, it is highly desirable that the composition have a rheology and a minimum of stability that is compatible with most commercial and retail requirements. Therefore, the composition of the present invention generally has a phase separation of less than 2% by volume after storage at 25 ° C. for 21 days from the time of production,
At a shear rate of 21 s ^-1 , the viscosity is less than 2.5 Pas, preferably 1
It is preferably less than Pas.

In the case of blends of primary and stabilizing surfactants, the exact ratio of each component that provides such stability and viscosity depends on the type and amount of electrolyte, as in the case of traditional structured liquids. Decided. Thus, by way of example, FIG. 1 shows a typical ternary stability curve for a blend of dodecyl benzene sulfonate (DoBS), C _12-15 fatty acid alcohol ethoxylated with an average of 7 moles of ethylene oxide and a stabilizing surfactant. The figure is shown. Trace I shows the limit for a stable composition at a certain electrolytic mass (eg 10% by weight). The dashed lines A, B, C have the following meanings for this limit.

A = minimum weight ratio of stabilizing surfactant to total surfactant amount (in this case 0.
06) B = The minimum weight ratio of ethoxylated fatty alcohol to the total amount of surfactant that can be stably added (here, 0.3
4) C = The minimum weight ratio of the compounded surfactant to the total amount of the surfactant to obtain a stable liquid detergent composition (here, 0.3
7) (Assuming that the stabilizing surfactant is non-ionic) Trace II shows the same limit at higher electrolytic mass (eg 12.5 wt%). It is understood that when determining compositional parameters at various electrolytic masses, it is necessary to modify the ratio of surfactants so that the test composition is always effectively in the same position with respect to the stability limit. Such adjustments must be made in the determination of thresholds A, B and C at various electrolytic masses, as shown in the examples below.

In such a three-component surfactant blend, the use of a stabilizing surfactant as a co-surfactant with one or more primary surfactants would be expected from the additive behavior of each two-component combination. The stability diagram gives a much larger stability region than the one. (That is, a stable composition can be obtained with a wide range of surfactant ratios.) Fig. 2 shows a system of 23% total surfactant, 10% sodium citrate and 67% water, and The agents were dodecylbenzesisulfonate, C _12-15 E ₇ and a stabilizing surfactant C _12-13 G ₃ (see (Note) at the end of Example 1).
Is. The ternary diagram a) shows the additive behavior expected from the binary system, and the diagram b) shows the actually observed stability region. [Note] The numbers on each axis in these diagrams indicate the ratio of each surfactant to all the surfactants in the composition.

In general, detergent active substances are composed of one or more surfactants, and in the case of both primary surfactants and stabilizing surfactants, they are anionic, cationic, nonionic, zwitterionic and zwitterionic. And mixtures thereof (if they are compatible with each other). For example, these are "Surfactants" Volume 1, Schwartz & Perry, Interscience 1949, and
"Surfactants" Volume II, Schwartz, Perry & Birch (Interscience 1958), Manufacturing,
Listed in "McKachchan Emulsifiers &Detergents" or "Tenside Pocketbooks" H. Stagghe, Second Edition, Karl Hansers Bookshop, Munich & Vienna, 1981, published by the McKachchan Division of Confectioners, Inc. You can select from class, subclass and specific substance.

In the case of primary surfactants, suitable nonionic surfactants are reaction products of compounds having a hydrophobic compound with compounds having a reactive hydrogen atom, such as aliphatic alcohols, aliphatic acids, aliphatic amides or alkylphenols. With the product obtained by reacting with alkylene oxide, especially ethylene oxide alone or a mixture with propylene oxide. Specific nonionic detergent compounds include alkyl (C ₆ -C ₁₈ ) 1 containing ethylene oxide.
There are products obtained by condensing ethylene oxide with a reaction product of a primary or secondary straight-chain or branched chain alcohol and propylene oxide and ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulfoxys.

The primary anionic detergent surfactant is usually a water-soluble alkali metal salt of organic sulfuric acid and sulfonic acid containing an alkyl group of about 8 to 22 carbon atoms. "Alkyl" here
The term includes the alkyl portion of higher acyl groups.

Examples of suitable synthetic anionic detergent compounds include sodium and potassium alkyl sulphates, especially those obtained by sulphating higher (C ₈ -C ₁₈ ) alcohols prepared from, for example, beef tallow or coconut oil, alkyl (C ₉ −
C ₂₀ ) Sodium and potassium benzene sulfonate,
Especially straight chain secondary alkyl (C ₁₀ -C ₁₅ ) sodium benzene sulfonates; sodium alkyl glyceryl ether sulfonates, especially ethers of higher alcohols derived from tallow or coconut oil and ethers of synthetic alcohols derived from petroleum; coconut oil fatty Monoguriserudo sulfur and sodium sulfonate; higher (C ₈ -
C ₁₈ ) Reaction products of sodium and potassium salts of sulfuric acid esters of fatty alcohols with alkylene oxides, especially ethylene oxide; Reaction products of fatty acids such as coconut fatty acid esterified with isethionic acid and neutralized with sodium hydroxide; Sodium and potassium salts of fatty acid amides; alpha olefins (C ₈ −
Alkanes such as those obtained by reacting C ₂₀ ) with sodium bisulfite, those obtained by reacting paraffin with SO ₂ and Cl ₂ and then hydrolyzing with a base to form a random sulfonate. Monosulfonate;
Examples thereof include olefin sulfonates obtained by reacting an olefin, particularly a C ₁₀ -C ₂₀ alpha olefin with SO _3, and then neutralizing and hydrolyzing the reaction product. The preferred anionic detergent compounds are (C ₁₁ -C ₁₅ ) sodium alkylbenzene sulfonate and (C ₁₆ -C).
_C18 ) is sodium alkylsulfate.

As primary surfactants, those derived from alkali metal soaps of fatty acids, especially acids containing 12 to 18 carbon atoms, such as oleic acid, linoleic acid, castor oil, rapeseed oil, peanut oil, coconut oil, palm kernel oil or mixtures thereof. Fatty acid soap may be included. You can use sodium or potassium soap of these acids,
Potassium soap is preferred.

The compositions of the present invention also include an amount of electrolyte sufficient to structure the detergent active material. The composition preferably contains 1% to 60%, especially 10 to 45% salting out electrolyte. The salting-out electrolyte refers to an electrolyte having a lyotropic number of 9.5 or less as described in EP-A-79646. For example, alkali metal or ammonium salts of ortho and pyrophosphate, alkali metal salts or ammonium salts of tripolyphosphate such as sodium tripolyphosphate, silicic acid, boric acid, carbonic acid, sulfuric acid, alkali metal salts or ammonium salts of citric acid, Mention may be made of alkali metal or ammonium salts of nitrilotriacetic acid and of carboxymethyloxysuccinic acid. Some salting
-In) electrolyte (as defined in EP-A-79646)
You may contain as needed as long as the kind and amount are compatible with other components. Such compositions are also within the scope of the invention. Some or all of the electrolytes (whether salt-soluble and salting-out electrolytes), or the substantially water-insoluble salts present, may have detergent builder properties. In any case, it is desirable that the composition according to the invention comprises a detergent builder substance. Some or all of the detergent builder materials may be electrolytes. Builder substances are substances that can reduce the amount of free calcium ions in the wash liquor and also have other advantageous properties such as the generation of alkaline pH, the suspension of dirt removed from the fabric, the dispersion of clay substances for fabric softening. What can be applied to the composition is desirable.

Examples of phosphorus-containing inorganic detergent builders include water-soluble salts, especially alkali metal pyrophosphates, orthophosphates, polyphosphates and phosphonates. Specific examples of the inorganic phosphate builder include sodium and potassium salts of tripolyphosphoric acid, phosphoric acid and hexametaphosphoric acid, respectively.

Examples of phosphorus-free inorganic detergent builders include water-insoluble alkali metal carbonates, bicarbonates, silicates and crystalline or amorphous aluminosilicates. Specific examples include sodium carbonate (including those with and without calcite nucleus), potassium carbonate, sodium and potassium bicarbonates and silicates, and zeolites.

Examples of organic detergent builders include alkali metal, ammonium and substituted ammonium polyacetyl carboxylates and polyhydroxy sulfonates. Specific examples are ethylenediaminetetraacetic acid, nitrilotriacetic acid,
Includes sodium, potassium, lithium, ammonium and substituted ammonium salts of oxydisuccinic acid, mellitic acid, benzene polycarboxylic acid, citric acid, tartrate disuccinic acid and tartrate monosuccinic acid.

Apart from the additives already mentioned, many other additives may be used if desired. For example, foam promoters such as alkanolamides, especially monoethanolamide derived from palm kernel oil fatty acids and coconut oil fatty acids, fabric softeners such as clays, amines and amine oxides, defoamers, oxygen release such as trichloroisocyanuric acid. Bleaching agents, inorganic salts such as sodium sulphate and fluorescent agents usually present in very small amounts, perfumes, enzymes such as proteases and amylases, fungicides and colorants.

The present invention will be further described based on the following examples.

[Brief description of drawings]

Figure 1 shows dodecylbenzene sulfonate (DoBS), C
Figure 3 shows a ternary stability diagram for a blend containing _12-15 fatty acid alcohol (7EO) and a stabilizing surfactant. Figure 2 a) and b) are DoBS, C _12-15 E ₇ and C
Predicted and measured values are shown for the three-component stability of the system containing _12-13 G ₃ .

Claims (11)

[Claims] 1. A stabilizer comprising a dispersion of lamellar drops containing a detergent active material and a salting-out electrolyte, wherein the detergent active material has an average alkyl chain length of 6 or more carbon atoms and a salting-out resistance of 6.4 or more. An aqueous liquid detergent composition comprising a surfactant. 2. A composition according to claim 1, wherein the detergent active material comprises a nonionic surfactant and / or a non-alkoxylated anionic surfactant and / or an alkoxylated anionic surfactant. 3. The stabilizing surfactant is selected from alkylpolyalkoxylated phosphates; alkylpolyalkoxylated sulfosuccinates; dialkyldiphenyloxide disulfonates; alkylpolysaccharides; and mixtures thereof. The composition according to 2. 4. The composition according to any one of claims 1 to 3, wherein at least one of the stabilizing surfactants or the stabilizing surfactants having a stabilizing surfactant has a salting-out resistance of 9.0 or more. 5. The composition according to claim 1, wherein the stabilizing surfactant has an average alkyl chain length of more than 8 carbon atoms. 6. The composition according to claim 1, wherein the detergent active material comprises 2 to 50% by weight of the total composition. 7. The composition according to claim 1, wherein the stabilizing surfactant constitutes 0.1 to 45% by weight of the total composition. 8. The stabilizing surfactant is 5 to 90% of the detergent active material.
The composition according to any one of claims 1 to 7, which accounts for weight%. 9. A salting-out electrolyte in an amount of 1 to 60% by weight.
9. The composition according to any one of to 8. 10. The composition according to claim 9, wherein the salting-out electrolyte constitutes 10 to 45% by weight of the total composition. 11. The phase separation does not exceed 2% by weight even when left at 25 ° C. for 21 days after production, and the viscosity is a shear rate of 21 s ^−1.
The composition according to claim 1, which does not exceed 1 Pas.