EP3230430B1 - Method for producing liquid compositions containing a surfactant and having a yield point - Google Patents

Description

The present invention relates to a process for the preparation of liquid compositions with yield point, which contain one or more surfactants, and the compositions obtained therefrom.

Liquid, surfactant-containing compositions have become indispensable in everyday life. On the one hand, these are personal care products such as shampoos, shower gels or bubble baths. But also washing or cleaning agents, such as household cleaners, fabric softeners, laundry detergents, floor care products, all-purpose cleaners, manual dishwashing detergents, automatic dishwashing detergents or heavy-duty detergents are included.

Much of these compositions are now produced in a batch process. The batch process, often referred to as batch production, is a discontinuous production process. Here, certain quantities of starting materials are conveyed according to a predetermined recipe in a container and mixed there. The capacity of the production vessel, in which all components are mixed together, limits the amount of material that is produced in a batch or a batch.

In a typical batch process or batch process, first a reaction vessel is completely filled with the starting materials, ie the educts. The reaction of the reactants with each other towards the final product takes place within the reaction vessel. Once the reaction has taken place, the reaction vessel is completely emptied and the desired formulation is filled into suitable containers for sale or optionally for storage. Then the reaction vessel has to be prepared for the next filling. This means a thorough cleaning of the reaction vessel and optionally the lines through which the starting materials are introduced into the reaction vessel, as well as the implementation of upcoming maintenance.

Such a batch process has the advantage that the formulation of the recipe can still be adjusted in the reaction vessel if necessary. Replenishment of individual components are possible here. In terms of quality, this must take into account the possibility of batch tracing.

The disadvantage, however, is the large footprint. A reaction vessel is always completely filled; that is, it will always be produced large quantities of a product. Once a batch (or batch) is made, it must be processed first before another batch batch approach can be made. Is not a direct processing or filling possible, an already manufactured product must be stored outside the reaction vessel. Again, this leads to a high space requirement and the creation of additional costs.

Furthermore, the change in production from one product to another requires a lot of effort. If, for example, a product is produced in a first batch process which has a specific colorant and a certain odorant substance, then, before a second product having a different color and odor profile is produced, the reaction vessel and all feed lines must be thoroughly cleaned so as to cause contamination the batches are avoided.

In addition to the batch batch process, continuous processes for the preparation of liquid surfactant-containing compositions are also known. Continuous processes offer better opportunities for just-in-time production. However, a complex control of the individual process steps is necessary here. In the continuous process, the mixing by means of static or dynamic mixing devices does not take place in a reaction vessel as in the batch process. Rather, the mixing takes place within a pipe. In this line, the individual ingredients of a recipe are dosed in a predefined order. At the end of this line immediately bottling. A re-dosing or changing the concentration of individual components is not possible here. Targeted and controlled monitoring of the addition of each constituent is necessary.

When manufacturing personal care, washing or cleaning agents, it should also be noted that the addition of solid ingredients may be necessary. However, these can only be added in a batch process. The addition of solid components in a continuous process is not possible. In continuous processes, only liquid components can be dosed.

However, the addition of solid additives to corresponding compositions belongs today to the state of the art. It is often problematic to suspend solids in liquids, especially when the solids differ in density from the liquid, they tend to sediment or float. The incorporation of certain active ingredients (for example, bleach enzymes, perfumes, dyes, etc.) in liquid detergents and cleaners can lead to problems. For example, incompatibilities between the individual active ingredient components of the liquid detergents and cleaners may occur. This can lead to undesirable discoloration, agglomeration, odor problems and destruction of detergent active ingredients.

The consumer, however, requires liquid detergents and cleaning agents which, even after storage and transport, develop optimally at the time of use. This requires that the contents of the liquid washing and cleaning agent have neither been previously deposited or decomposed nor volatilized. A concept for the incorporation of sensitive, chemically or physically incompatible as well as volatile components consists in the use of particles and in particular microcapsules in which these ingredients are trapped stable storage and transport.

In order to generate a stable network in personal care, washing or cleaning agents, in which solids can be stably suspended, so-called structuring agents are often used, which usually after activation with the remaining constituents of the formulation, such as surfactants, solvents or builders are mixed together, whereby a structured product is obtained by producing a flow limit. Such external structuring can be achieved, for example, by the use of structuring gums, such as xanthan gum, guar gum, locust bean gum, gellan gum, wellar gum or carrageenan or of polyarcrylate thickeners. From an aesthetic point of view, it is desirable for the agents to be transparent or at least translucent. However, the use of structuring gums often results in cloudy compositions.

In the WO 00/36078 describes transparent / translucent liquid detergents which are capable of suspending particles in a size of 300 to 5000 microns, comprising at least 15 wt .-% of surfactant and 0.01 to 5 wt .-% of a polymeric gum. The application contains no information as to whether the liquid detergents have yield points.

In the WO 2013/160022 For example, yield-point compositions containing activated citrus fibers as external structurants are prepared.

Another disadvantage of using these structuring or thickening agents is their sensitivity to ionic compounds, in particular to anionic surfactants which are obligatory in cleaning applications.

At high concentrations of polymeric thickeners in systems with simultaneously high concentrations of anionic surfactants, drastic increases in viscosity can occur, which severely impair the handling of the detergents and cleaners (for example, pumping, pouring or metering). It is also not always possible to produce flow limits in systems rich in electrolyte and / or surfactants.

In other cases, flow limits can be achieved by forming a lamellar structure of the surfactants. In this case, certain amounts of surfactants, cosurfactants and inorganic salt are mixed together to change the originally micellar structure of the surfactants by means of co-surfactants and salts in a lamellar structure. Corresponding structured means are for example in WO 2013/064357 A1 described in detail.

In the EP 1 466 959 A1 are flow-containing formulations having high levels of anionic surfactants described that have no polymeric thickener, but anionic and cationic surfactants in a specific, effective for generating a yield point ratio.

In the production of appropriately structured flow-limit agents in a batch batch process, the manufacturing process is associated with the introduction of air into the composition to be produced. This is disadvantageous because fluctuations in density due to variable air intake make a reproducible and constant filling much more difficult, if not impossible. In addition, there is the possibility that the air bubbles begin to float at low flow limits and thereby cause the separation of the composition.

Therefore, in order to achieve a stable structured product with a yield point in which solids can be homogeneously suspended, it would be desirable to provide a process in which the entry of air can be avoided. A solution is in here WO 2011/056953 A1 and in WO 2011/056947 A1 proposed. Here, the product is prepared in a conventional manner in a batch process and then degassed. Alternatively, the resulting product could be deaerated in a centrifuge. Both methods, however, increase the apparatus required for the production. In addition, the equipment required is costly and production flexibility and capacity are adversely affected. Furthermore, not all constituents contained in a liquid composition are so stable that they are stable in a venting process in a vacuum or the centrifugal forces occurring in a centrifugation, so that in particular the new or further development of formulations is difficult.

There is therefore a need to provide a method by which liquid surfactant-containing compositions can be produced with yield stress. In the process, no or as little as possible air should be added to the composition. Not only liquid but also solid starting materials should be used as starting materials.

A fabric, e.g. a composition according to the definition of the invention is solid when in the solid state at 25 ° C and 1013 mbar.

A fabric, e.g. a composition according to the definition of the invention is liquid when in liquid state at 25 ° C and 1013 mbar. In this case, liquid also includes gel.

Surprisingly, it has been found that an approximately air-free production process, in which both liquid and solid starting materials can be used, realized thereby can be that in a first step in a batch process, a basic recipe is prepared, which is then differentiated in a second step.

1. i) in der kontinuierlichen Anlage alle Stoffe in flüssiger Form in eine Leitung zusammen dosiert und mittels dynamischer und/oder statischer Mischer homogenisiert werden und
2. ii) das kontinuierliche Verfahren bei einem gegenüber dem Umgebungsdruck erhöhten Druck von 0,5 bis 6 bar durchgeführt wird.

The object underlying the present invention is therefore achieved by a process for producing a liquid, surfactant-containing composition having a yield point of from 0.01 Pa to 50 Pa, in which in a first step in a batch process a base formulation comprising at least one surfactant and at least one Solvent prepared and this basic formulation is differentiated in a subsequent second step in a continuous process, wherein

1. i) in the continuous plant all substances in liquid form are metered together in a line and homogenized by means of dynamic and / or static mixer and
2. ii) the continuous process is carried out at a relative to the ambient pressure increased pressure of 0.5 to 6 bar.

The composition according to the invention has a yield point. In the rheology, the yield point is understood as the shear stress (in Pa) below which a specimen exclusively or at least largely elastically deforms and above which an irreversible, plastic deformation, ie, a flow, takes place.

The yield strength of the liquid, surfactant-containing composition is measured using a TA-Instruments, type AR G2 absolute rotary rheometer (shear stress controlled rheometer, cone-plate measuring system with 40 mm diameter, 2 ° cone angle, 20 ° C.). This is a so-called shear stress controlled rheometer. Here, the samples in the rheometer with a time-increasing shear stress σ (t) are applied. For example, the shear stress can be increased from the lowest possible value (for example, 0.01 Pa) to, for example, 100 Pa in the course of 30 minutes. As a function of this shear stress σ, the deformation γ of the sample is measured. The deformation is plotted against the shear stress in a log-log plot (log γ against log σ). If the tested sample has a yield point, it can be recognized by a sudden change in the curve. Below a certain shear stress, one finds a purely elastic deformation. The slope of the curve γ ( σ ) (log-log plot) in this area is one. Above this shear stress begins viscous flow and the slope of the curve is suddenly higher. The shear stress at which the bending of the curve takes place, ie the transition from the elastic to a plastic deformation, marks the yield point. A convenient determination of the yield stress (= bend of the curve) is possible by applying tangents to the two curve parts. Samples without yield point do not show a characteristic kink in the function γ (σ).

The composition produced according to the invention preferably has a yield point in the range from 0.01 Pa to 50 Pa, preferably from 0.1 Pa to 10 Pa, particularly preferably from 0.5 Pa to 5 Pa. In this case, those compositions are particularly preferred which have a yield point of not more than 10 Pa. Such are particularly well filled and well dosed by the consumer.

According to the invention, the base formulation comprises at least one surfactant and at least one solvent. The base formulation may thus have one or more surfactants. These surfactants are selected from the group consisting of anionic, cationic, zwitterionic, nonionic surfactants and mixtures thereof. If the composition comprises a plurality of surfactants, these may be, for example, several different nonionic surfactants. However, it is also possible that the composition comprises, for example, both nonionic and anionic surfactants. This applies analogously to the other surfactants. Preferably, the base formulation comprises at least one anionic surfactant and at least one nonionic surfactant.

The level of surfactant in the final composition is preferably 0.1-40% by weight of surfactant, more preferably 5% to 30% by weight of surfactant, even more preferably 10-25% by weight of surfactant.

If the base formulation comprises an anionic surfactant, this is preferably selected from the group consisting of C _9-13 -alkylbenzenesulfonates, olefinsulfonates, C _12-18 -alkanesulfonates, ester sulfonates, alk (en) ylsulfates, fatty alcohol crude ether sulfates and mixtures thereof. It has been found that these sulfonate and sulfate surfactants are particularly suitable for the preparation of stable liquid compositions with yield point. Liquid compositions comprising as anionic surfactant C _9-13 -alkylbenzenesulfonates and fatty alcohol ether sulfates have particularly good dispersing properties. Preferred surfactants of the sulfonate type are C _9-13 -alkylbenzenesulfonates, olefinsulfonates, that is to say mixtures of alkene and hydroxyalkanesulfonates and also disulfonates, as are obtained, for example, from C _12-18 -monoolefins having terminal or internal double bonds by sulfonation with gaseous Sulfur trioxide and subsequent alkaline or acid hydrolysis of the sulfonation obtained. Also suitable are C _12-18 alkanesulfonates and the esters of α-sulfo fatty acids (ester sulfonates), for example the α-sulfonated methyl esters of hydrogenated coconut, palm kernel or tallow fatty acids.

Alk (en) ylsulfates are the alkali metal salts and, in particular, the sodium salts of the sulfuric monoesters of C ₁₂ -C ₁₈ fatty alcohols, for example coconut fatty alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl or stearyl alcohol or the C ₁₀ -C ₂₀ oxo alcohols and those half-esters of secondary alcohols of these chain lengths are preferred. Of washing technology interest, the C ₁₂ -C ₁₆ alkyl sulfates and C ₁₂ -C ₁₅ alkyl sulfates and C ₁₄ -C ₁₅ alkyl sulfates are preferred. 2,3-alkyl sulfates are also suitable anionic surfactants.

Also, fatty alcohol ether sulfates, such as the sulfuric acid monoesters of straight-chain or branched C _7-21 -alcohols ethoxylated with from 1 to 6 mol of ethylene oxide, such as 2-methyl-branched C _9-11- alcohols having on average 3.5 mol of ethylene oxide (EO) or C _{12 -18} fatty alcohols with 1 to 4 EO are suitable.

It is preferred that the liquid composition prepared according to the invention contains a mixture of sulfonate and sulfate surfactants. In a particularly preferred embodiment, the liquid composition C _9-13 alkylbenzenesulfonates and fatty alcohol ether sulfates as anionic surfactant.

In addition to the anionic surfactant, the liquid composition in the base formulation may also contain soaps. Suitable are saturated and unsaturated fatty acid soaps, such as the salts of lauric acid, myristic acid, palmitic acid, stearic acid, (hydrogenated) erucic acid and behenic acid and, in particular, soap mixtures derived from natural fatty acids, for example coconut, palm kernel, olive oil or tallow fatty acids.

The anionic surfactants and the soaps may be in the form of their sodium, potassium or magnesium or ammonium salts. Preferably, the anionic surfactants are in the form of their sodium salts. Further preferred counterions for the anionic surfactants are also the protonated forms of choline, triethylamine, monoethanolamine or methylethylamine.

The base formulation may also comprise at least one nonionic surfactant in addition to the anionic surfactant. The nonionic surfactant includes alkoxylated fatty alcohols, alkoxylated fatty acid alkyl esters, fatty acid amides, alkoxylated fatty acid amides, polyhydroxy fatty acid amides, alkylphenol polyglycol ethers, amine oxides, alkyl polyglucosides, and mixtures thereof.

The nonionic surfactant used are preferably alkoxylated, advantageously ethoxylated, in particular primary, alcohols having preferably 8 to 18 carbon atoms and on average 4 to 12 moles of ethylene oxide (EO) per mole of alcohol, in which the alcohol radical may be linear or preferably methyl-branched in the 2-position or may contain linear and methyl-branched radicals in the mixture, as they are usually present in Oxoalkoholresten. In particular, however, alcohol ethoxylates having linear radicals of alcohols of native origin having 12 to 18 carbon atoms, for example coconut, palm, tallow or oleyl alcohol, and on average 5 to 8 EO per mole of alcohol are preferred. The preferred ethoxylated alcohols include, for example, C _12-14 alcohols with 4 EO or 7 EO, C _9-11 alcohols with 7 EO, C _13-15 alcohols with 5 EO, 7 EO or 8 EO, C _12-18 Alcohols with 5 EO or 7 EO and mixtures of these. The degrees of ethoxylation given represent statistical means which, for a particular product, may be an integer or a fractional number. Preferred alcohol ethoxylates have a narrow homolog distribution (narrow range ethoxylates, NRE). In addition to these nonionic surfactants, fatty alcohols with more than 12 EO can also be used. Examples include tallow fatty alcohol with 14 EO, 25 EO, 30 EO or 40 EO. Nonionic surfactants containing EO and PO groups together in the molecule can also be used according to the invention. Also suitable are also a mixture of a (more) branched ethoxylated fatty alcohol and an unbranched ethoxylated fatty alcohol, such as a mixture from a C _16-18 fatty alcohol with 7 EO and 2-propylheptanol with 7 EO. With particular preference, the washing, cleaning, after-treatment or washing assistant contains a C _12-18 fatty alcohol with 7 EO or a C _13-15 oxo alcohol with 7 EO as nonionic surfactant.

The composition prepared according to the invention further comprises one or more solvents in its basic formulation. These may be water and / or non-aqueous solvents. Preferably, the base formulation contains water as the main solvent. The masterbatch may further comprise non-aqueous solvents. Suitable non-aqueous solvents include monohydric or polyhydric alcohols, alkanolamines or glycol ethers. Preferably, the solvents are selected from ethanol, n-propanol, i-propanol, butanols, glycol, propanediol, butanediol, methylpropanediol, glycerol, diglycol, propyldiglycol, butyldiglycol, hexylene glycol, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol methyl ether, Diethylene glycol ethyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, methoxytriglycol, ethoxytriglycol, butoxytriglycol, 1-butoxyethoxy-2-propanol, 3-methyl-3-methoxybutanol, propylene glycol t-butyl ether, di-n-octyl ether and mixtures thereof Solvent.

In the first step of the process according to the invention, a basic formulation is prepared in a conventional batch process or batch process, which in particular has a viscosity of 1000 mPa · s or less, in particular 200 to 800 mPa · s, especially 400 to 700 mPa · s. The viscosity is determined at a temperature of 20 ° C (Viscometer HATDV II from Brookfield, 20 rpm spindle 2). In the batch process the basic formula air is added. Due to the low viscosity, however, this air can escape from the basic formulation within a very short time without any intervention, so that in effect an approximately air-free product is obtained.

In addition to the at least one surfactant and the at least one solvent, the base formulation may further comprise builders and / or alkaline substances. As builders, for example, polymeric polycarboxylates are suitable. These are, for example, the alkali metal salts of polyacrylic acid or polymethacrylic acid, for example, those having a molecular weight of 600 to 750,000 g / mol.

Suitable polymers are in particular polyacrylates, which preferably have a molecular weight of from 1,000 to 15,000 g / mol. Because of their superior solubility, the short-chain polyacrylates, which have molecular weights of from 1,000 to 10,000 g / mol, and particularly preferably from 1,000 to 5,000 g / mol, may again be preferred from this group.

Also suitable are copolymeric polycarboxylates, in particular those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with maleic acid. To improve the water solubility, the polymers may also contain allylsulfonic acids, such as allyloxybenzenesulfonic acid and methallylsulfonic acid, as a monomer.

As builders which may be present in the composition produced according to the invention, in particular silicates, aluminum silicates (in particular zeolites), carbonates, salts of organic di- and polycarboxylic acids and mixtures of these substances may be mentioned.

Organic builders which may furthermore be present in the composition prepared according to the invention are, for example, the polycarboxylic acids which can be used in the form of their sodium salts, polycarboxylic acids meaning those carboxylic acids which carry more than one acid function. These are, for example, citric acid, adipic acid, succinic acid, glutaric acid, malic acid, tartaric acid, maleic acid, fumaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), methylglycinediacetic acid (MGDA) and derivatives thereof and mixtures thereof. Preferred salts are the salts of polycarboxylic acids such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures thereof.

However, preference is given to using soluble builders, such as, for example, citric acid, or acrylic polymers having a molar mass of from 1,000 to 5,000 g / mol in the basic formulation.

For the purposes of the present invention, alkaline substances or wash alkalis are chemicals for raising and stabilizing the pH of the composition.

In particular, those constituents of the composition are preferably added to the basic formulation in the batch process, which can be metered exclusively in a batch process. These are in particular those components which are present exclusively as a solid and thus can not be introduced into a composition in a continuous process. For example, this relates to citric acid and its salts, such as sodium citrate, or boric acid. These must be introduced as a solution or suspension.

According to the invention, a differentiation of the basic formulation then takes place in a second step following the first step. This takes place in a continuous process. It is possible to directly transfer the basic formulation obtained in the first step into a continuous process. However, it is also possible to initially store the basic recipe and use it only when needed in the continuous process.

Differentiation in the sense of the present invention means that a basic formulation which is the same for several different liquid, surfactant-containing compositions is then differentiated to the actual desired end product. In this second step, only the substances are added to the base formulation, which are important for the characteristics of the end product, that is the inventively prepared liquid, surfactant-containing composition, such as dyes, perfume compositions, enzymes dyes, perfume capsules, microbeads, opacifiers, color Transfer inhibitors (dye transfer inhibitors DTI), brighteners, saline solutions, cosurfactants or water.

The continuous process is characterized in that there is an overpressure within the plant in which the continuous process takes place. The basic recipe is passed through a pipe system. By means of pumps, the flow rate of the composition and thus the pressure in the pipe system is controlled. Pressure sensors attached to the piping system allow feedback to the pumps to control the pressure within the piping system. For example, pressure sensors of the company Endress and Hauser, Germany can be used. The line into which the basic formulation is introduced is called the main stream. In this line, the other components are dosed to differentiate the basic formula. The continuous process under overpressure allows to avoid a gas / air entry into the composition. The continuous process is carried out at a relative to the ambient pressure increased pressure of 0.5 to 6 bar, in particular from 0.5 to 4 bar.

In this continuous process, all substances in liquid form are dosed together in a single line in a continuous plant and homogenized by means of dynamic and / or static mixers. Since they can only be operated with liquid substances, according to the invention, in the second step, only liquid products can be used to differentiate the basic formulation. Liquid products within the meaning of the present invention are liquids or solutions of solids in a suitable solvent as well as stable suspensions, dispersions or emulsions.

The differentiation runs along the main stream, through which the basic formula flows. In this case, the compositions to be metered can be premixed and dosed together into the main stream or individually or in different combinations of eg 2-3 components are metered via separate feed lines in the main stream. It is preferred that at the point at which the metering takes place in the main stream, a mixer, in particular a static mixer, which ensures the rapid and homogeneous distribution of the metered means in the main stream. In this case, for example, dyes, microcapsules and perfume can be metered separately from each other in the stream. From the introduction of the basic recipe, the perfume can be used first, and the dye in a subsequent step be dosed. The order of dosing can also be done in reverse order, ie first dye and then perfume. In principle, it is preferred to dose such substances as last, which change the basic formulation even in small amounts. If, for example, a dye is first dosed into the basic formulation and only in a later step is the perfume or another substance, the path taken by the dye through the system is long, so that when changing the recipe, significantly more cleaning effort has to be done to remove the last traces of dye. Therefore, it may be advantageous to dose dyes last in the main stream to allow a quick and favorable change of the dye. Also the place of dosage of perfume is to be determined in this regard. However, for the consumer, the visual perception is stronger than the odor-specific, so in case of doubt, the colorant to be dosed after the perfume, to avoid that the consumer perceives unintentional product discoloration by recipe change.

According to the invention, the differentiation is effected in particular by the addition of one or more cosurfactants and / or one or more electrolytes. The co-surfactant or the co-surfactants change the micellar structure of the surfactants in the basic formulation. By one or more electrolytes, this effect can be strengthened. This results in a lamellar structure of the surfactants. Corresponding structured detergents or cleaning agents with yield point are in the prior art, for example in WO 2013/064357 A1 described. The content of this application is fully incorporated by reference.

Co-surfactants for the purposes of the present invention are amphiphilic molecules with a small, hydrophilic head group. In a binary system with water, these co-surfactants are often only weakly or not at all soluble. Accordingly, they do not form micelles there either. In the presence of the surfactants of the basic formulation, the co-surfactants are incorporated into their associates, thereby changing the morphology of these associates. The spherical micelles become rod-shaped and / or disc-shaped micelles. With a sufficiently high total surfactant content, lamellar phases or structures are formed.

The cosurfactant is preferably selected from the group consisting of alkoxylated C ₈ -C ₁₈ fatty alcohols having a degree of alkoxylation ≦ 3, aliphatic C ₆ -C ₁₄ -alcohols, aromatic C ₆ -C ₁₄ -alcohols, aliphatic C ₆ -C ₁₂ Dialcohols, monoglycerides of C ₁₂ -C ₁₈ fatty acids, monoglycerol ethers of C ₈ -C ₁₈ fatty alcohols, and mixtures thereof. Other suitable cosurfactants are 1-hexanol, 1-heptanol, 1-octanol, 1,2-octanediol, stearic monoglycerol and mixtures thereof.

Also suitable are fragrance alcohols such as geraniol, nerol, citronellol, linalool, rhodinol and other terpene alcohols or fragrance aldehydes such as lilial or decanal as co-surfactants.

Preferred cosurfactants are C ₁₂ -C ₁₈ fatty alcohols having a degree of alkoxylation ≦ 3. These cosurfactants are particularly well incorporated into the preferred anionic and nonionic surfactant associates.

Suitable alkoxylated C ₁₂ -C ₁₈ fatty alcohols having a degree of alkoxylation ≦ 3 include, for example, iC ₁₃ H ₂₇ O (CH ₂ CH ₂ O) ₂ H, iC ₁₃ H ₂₇ O (CH ₂ CH ₂ O) ₃ H, C _12-14 -Alcohol with 2 EO, C _12-14 -alcohol with 3 EO, C _13-15 -alcohol with 3 EO, C _12-18 -alcohols with 2 EO and C _12-18 -alcohols with 3 EO.

An electrolyte in the sense of the present invention is an inorganic salt. Preferred inorganic salts include sodium chloride, potassium chloride, sodium sulfate, sodium carbonate, potassium sulfate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, calcium chloride, magnesium chloride, and mixtures thereof. Particularly stable compositions are obtained using sodium chloride or mixtures of sodium chloride and potassium sulfate.

The addition of the inorganic salt promotes the formation of lamellar structures. In addition, the inorganic salt has an influence on the viscosity, so that the viscosity of the liquid composition can be adjusted by means of the inorganic salt.

It is particularly advantageous to prepare the lamellar structured liquids according to the process of the invention, since smaller amounts of surfactant and / or electrolyte are sufficient to form lamellar structures that stabilize optically perceivable particles because of the low gas / air content in the liquid composition. The prior art processes require a significantly higher concentration of surfactant and / or electrolyte in order to stabilize the air and thus also the optical particles in the individual structured layers. When compared to the compositions of the present invention having the same surfactant and / or electrolyte concentration, the compositions prepared according to prior art methods can not or not to the same extent stabilize the gas / air entries in the compositions such that the lamellar structure is enhanced by buoyancy of the gas bubbles is at least partially destroyed and mix in the individual layers located components. In particular, optical particles can attach to the gas bubbles and be floated with. Thus, it becomes difficult to evenly distribute optical particles in the composition.

Preferably, the flow limit is produced by the dosage of the cosurfactants and / or one or more electrolytes in the continuous process. This has the advantage that the components metered in the continuous process are the same in the desired lamellar structure. In particular, the proportion of cosurfactants and / or electrolytes in the final liquid, surfactant-containing composition having a yield point of up to 15% by weight, preferably up to 10% by weight, more preferably up to 5% by weight.

Preferably, the base formulation in the second step further dispersed particles are added for differentiation. Dispersed particles in the sense of the present invention are not soluble in the solvent of the basic formulation. They can, however, be dispersed therein. The inventive method allows a homogeneous distribution and stable dispersion of these particles. According to the invention, these dispersed particles may be functional and / or have an aesthetic function. Functional materials affect the effect of the composition, whereas aesthetic materials only affect the appearance or odor. Preferably, the dispersed particles are visible particles. This means that the particles are clearly visible to the consumer with the eye in the composition (in the final product) and to be distinguished from the other constituents. Preferably, colored particles are meant herewith. Such particles give the composition a special impression that is appreciated by consumers. More preferably, the composition may contain a dissolved dye and, in addition, colored particles having a color that is a contrasting color to the dissolved dye.

Functionally dispersed particles may be capsules, abrasives, granules or compounds for the purposes of the present invention. The term capsule means on the one hand aggregates with a core-shell structure and on the other hand aggregates with a matrix. Core-shell capsules (microcapsules, microbeads) contain at least one solid or liquid core, which is enclosed by at least one continuous shell, in particular a shell of polymer (s).

Inside the capsules, sensitive, physically incompatible and volatile components (= active ingredients) of the liquid composition can be enclosed stable in storage and transport. The capsules may include, for example, optical brighteners, surfactants, complexing agents, bleaches, bleach activators, bleach catalysts, dyes and fragrances, antioxidants, builders, enzymes, enzyme stabilizers, antimicrobial agents, graying inhibitors, anti-redeposition agents, pH adjusters, electrolytes, detergency boosters, vitamins , Proteins, foam inhibitors and / or UV absorbers. The fillings of the capsules may be solids or liquids in the form of solutions or emulsions or suspensions.

The dispersed particles may have a density which corresponds to that of the liquid composition. According to the invention, this means that the density of the dispersed particles corresponds to 90% to 110% of the composition. However, it is also possible that the dispersed particles have a different density. Nevertheless, it is due to the invention Method also possible here to obtain a uniform dispersion of the particles in the composition. They can consist of different materials such as alginates, gelatin, cellulose, agar, waxes or polyethylenes. Particles which do not have a core-shell structure may also have an active ingredient in a matrix of a matrix-forming material. Such particles are referred to as "speckles". The matrix formation in these materials takes place for example via gelation, polyanion-polycation interaction or polyelectrolyte-metal ion interaction and is well known in the art as well as the production of particles with these matrix-forming materials.

The composition produced according to the invention has a yield strength of from 0.01 Pa to 50 Pa, preferably from 0.1 Pa to 10 Pa, particularly preferably from 0.5 Pa to 5 Pa. The composition is characterized in particular in that it has a viscosity measured at 20 ° C of 50,000 mPa · s or less, in particular 3000 mPa · s or less. The compositions of the invention differ from the known compositions by their lower gas / air content and the higher density associated therewith. As a result, the lamellar structures remain stable longer. Particles in the composition do not accumulate on the surface of the composition as is usual. Thus, the compositions are well fillable without the particles floating after bottling or storage. The absence or lower proportion of gas / air ensures that the composition can be filled more precisely. In addition, the composition has more surfactant per volume, so that the washing power per volume is higher than in conventional compositions.

In the present application, the viscosity of a composition refers to each with a Brookfield viscometer HATDV II with spindle 2 at 20 U / min at 20 ° C certain value.

The composition is in particular a body care, washing or cleaning agent. Personal care, detergents or cleaning agents in the context of the present invention include cosmetics, household cleaners, fabric softeners, laundry detergents, floor care products, all-purpose cleaners, dishwashing detergents for manual and machine cleaning, heavy-duty detergents, shampoos, shower gels and bubble baths. It is preferably a washing or cleaning agent.

The process according to the invention allows freedom from air in the product and thus improved product stability compared to processes described in the prior art. A "one pass" production enables targeted uniform homogenization. Investment costs can be reduced because the product formulation is based on a basic formulation that can be prepared in a simple process. This once made Basic recipe can then be used for different products. This saves the storage of batches of end products that are not immediately put on sale. This will reduce energy and production costs while increasing the capacity of existing facilities.

The process according to the invention is carried out during the continuous differentiation under overpressure. As overpressure, pressure of at least 0.1 bar above atmospheric pressure is considered. The overpressure prevents gases, especially air, from being introduced during differentiation of the composition. Thus, a product is obtained which is more air-free than products originating from a batch process. This makes it possible to dose the composition more reliably and accurately. Because less gas is included in the compositions of this invention, they have a higher density than comparative compositions.

EXAMPLES

The quantities in the exemplary embodiments are in% a.s., In% active substance. The data refer in all examples to 100% of the final product.

In the batch process (Example 1, Example 2a) was stirred with a stirrer from Intermig at a speed of 30 to 40 revolutions / min.

In the exemplary embodiments, water was initially introduced in a batch kettle. The amount of water, which is presented here, is about 50 wt .-% to 60 wt .-% based on 100 wt .-% of the final product. The choice of the exact amount is within the usual scope of the expert and depends on the desired end product. It should be noted that water can also be added by adding other ingredients. The content of water in the end product may according to the invention be from 60% by weight to 75% by weight.

1st batch process (prior art):

A liquid, surfactant-containing composition was prepared in a conventional batch process. For this purpose, water was placed in a 35 m ³ batch kettle. While stirring, 1.9% of NaOH, 1% of boric acid and 2% of citric acid were added. After the added components had dissolved (after stirring for about 5 minutes), a complexing agent (diethylenetriaminepenta (methylenephosphonic acid) in the form of 7 sodium salt (DTPMP · 7Na)) was added in an amount of 0.7% as. After stirring for about 5 minutes, 6.5% of surfactants (2.0% of niotenside (nonionic surfactant) having 12 to 18 carbon atoms and 7 mol of EO / mol, 4.0% of linear alkylbenzenesulfonate having 10 to 13 C Atoms and 0.5% of a fatty acid with 12 to 18 carbon atoms and low odor) was added and stirred for a further 15 minutes. Subsequently, an additional 8% of an anionic surfactant (alkyl ether sulfate with C ₁₂ chain) was added and incorporated by stirring (about 15 minutes). The temperature was about 55 ° C to 60 ° C.

Subsequently, the aqueous solution was cooled to a temperature of about 30 to 32 ° C. In the following, 0.03% as of a defoamer, 2% as ethanol as a solvent, 0.1% as a preservative and 0.35% as of brighteners were added. After these were evenly distributed, 0.2% perfume capsules, 1.1% as perfume and 0.28% as color solutions were added and also incorporated. Subsequently, enzymes (1.16% as), a saline solution (3% as), a nonionic surfactant (isotridecanol with 3 moles EO / mole) (2% as) and microbeads (0.25% as) were incorporated. The resulting mixture was thoroughly stirred and then bottled in the usual way.

The air-containing product obtained by the conventionally produced process shows a milky appearance. The density was 0.927 g / cm ³ . The density was measured with a pycnometer from Erichsen (model 290). The method complies with the requirements of DIN 53217 (ISO 2811-1) and the regulations cited therein. The measurement was carried out at a temperature of 23 ± 0.5 ° C.

2. Method according to the invention a) Preparation of the basic formula:

A surfactant-containing composition was prepared according to the method of the invention. First, water was placed in a batch kettle. With stirring, NaOH (2.3% as), boric acid (1.2% as) and citric acid (2.4% as) were added. After being dissolved in the water, diethylenetriaminepenta (methylenephosphonic acid) was added in the form of the sodium salt (DTPMP · 7Na) (0.85% as). Subsequently, surfactants (nonionic surfactant (nonionic surfactant) having 12 to 18 carbon atoms and 7 moles EO / mol (2.4% as), linear alkylbenzenesulfonate having 10 to 13 carbon atoms (4.8% as) and a fatty acid with 12 to 18 carbon atoms and low odor (0.6% as)) incorporated with stirring. After thorough stirring, another anionic surfactant (alkyl ether sulfate with C ₁₂ chain, 9.7% as) was incorporated. The temperature was about 55 ° C to 60 ° C.

After cooling to a temperature of about 30 to 32 ° C, defoamers (0.04% a.s.), ethanol (2% a.s) and preservatives (0.1% a.s.) were incorporated. The preparation of this basic formulation was carried out as in the known batch process (Example 1).

The viscosity of the basic formulation was 750 mPa s at 20 ° C. The viscosity was determined using a Brookfield viscometer HATDV II with spindle 2 at 20 rpm at 20 ° C.

b) Differentiation of the basic formula:

Subsequently, a part of the basic formulation was differentiated in a continuous process. For this, the composition of the batch was pumped into a line system. The diameter of the main pipe was 65 mm. The flow rate was in the range of 0.5 to 1.9 m / s. The pressure in the line system was 0.1 to 6 bar above normal pressure.

• Aufheller (0,35% Lösung im VE (vollentsalztem) Wasser (0,035% a.s.))
• Parfümkapseln (0,2% a.s.)
• Parfüm (1,1% a.s.)
• ggf. NaOH
• Enzyme (1,16% a.s.)
• Farblösungen (0,28% a.s.)
• NaCl Lösung (20% oder 25%ige Lösungen in VE Wasser) (3% a.s.)
• Niotensid (Isotridecanol mit 3 mol EO/mol) (2% a.s.)
• Microbeads (0,25% a.s.)

The main stream, which consists of the basic formula, was 82.7% of the final product. In this main stream, so the basic formula, the following additives were metered via side streams (the figures here also refer to the amount contained in the final product, the end product corresponds to 100%):

• Brightener (0.35% solution in demineralized water (0.035% as))
• Perfume capsules (0,2% as)
• Perfume (1,1% as)
• if necessary NaOH
• Enzymes (1,16% as)
• Color solutions (0,28% as)
• NaCl solution (20% or 25% solutions in deionised water) (3% as)
• Nonionic surfactant (isotridecanol with 3 mol EO / mol) (2% as)
• Microbeads (0,25% as)

The air-free product thus produced in the process according to the invention had a higher density of 1.062 g / cm ³ . The determination was carried out, as indicated above, also here in a pycnometer according to DIN 53217. The measurement was carried out at a temperature of 23 ± 0.5 ° C. The viscosity was 1500 to 2500 mPa s. The viscosity was determined using a Brookfield viscometer HATDV II with spindle 2 at 20 rpm at 20 ° C. The yield value of the composition was 2.1 Pa.

Both composition 1) and 2b) contained core-shell particles (microbeads), which clearly represented red dots in the composition. While the particles in the air-containing product (Example 1, prior art) swell up after a short time (since air attaches to them), these particles were uniformly distributed in the product in the air-free composition according to the invention (Example 2).

Claims (9)

1. A method for preparing a liquid, surfactant-containing composition having a yield point in the range of from 0.01 Pa to 50 Pa, in which

   - in a first step, in a batch process, a basic formula, comprising at least one surfactant and at least one solvent, is prepared and,

   - in a subsequent, second step, said basic formula is differentiated in a continuous method, wherein

   i) in the continuous system all material is metered together in liquid form into one line and homogenized by means of a dynamic and/or static mixer and

   ii) the continuous method is carried out at a pressure of from 0.5 to 6 bar, which pressure is elevated compared with the ambient pressure.
2. The method according to claim 1, characterized in that the composition has a yield point in the range of from 0.1 Pa to 10 Pa, particularly preferably from 0.5 Pa to 5 Pa.
3. The method according to claim 1 or 2, characterized in that the basic formula has a viscosity of 1000 mPa·s or less, in particular 200 to 800 mPa·s, particularly 400 to 700 mPa·s, the viscosity being determined using a Brookfield viscometer HATDV II having spindle 2 at 20 rpm at 20 °C.
4. The method according to one of claims 1 to 3, characterized in that the basic formula further comprises builders and/or alkaline substances.
5. The method according to one of claims 1 to 4, characterized in that the continuous method is carried out at a pressure of from 0.5 to 4 bar, which pressure is elevated compared with the ambient pressure.
6. The method according to one of claims 1 to 5, characterized in that the differentiation is carried out by adding one or more co-surfactants and/or one or more electrolytes, in particular the proportion of co-surfactants and/or electrolytes being up to 15 wt.%, preferably up to 10 wt.%, even more preferably up to 5 wt.%, of the final liquid, surfactant-containing composition having a yield point.
7. The method according to one of claims 1 to 6, characterized in that, in the second step, dispersed particles are further added to the basic formula for the differentiation.
8. The method according to claim 7, characterized in that the particles are visible particles.
9. The method according to claim 7 or 8, characterized in that the particles are microcapsules.