EP1356857A1 - Method for producing dispersantless Oil-in-Water dispersions - Google Patents

Abstract

Preparation of a dispersing agent-free oil in water dispersion, e.g. for manufacturing a separating agent, a cooling lubricant and/or a plant protection agent, with a viscosity of less as 10000 mPas, preferably less than 1000 mPas, comprises mixing at least a first aqueous phase and at least a further immiscible phase, without addition of a dispersing agent by intensively applying energy at least 5 seconds to obtain a stable dispersion. Independent claims are also included for: (1) process for the continuous production of a dispersing agent-free dispersion, in particular for the continuous production of a separating agent or a cooling lubricant, from at least two immiscible phases, by supplying the 2 phases intensively with energy for at least 5 seconds and without addition of a dispersing agent to form a stable dispersion, followed by separation of the phases in a separating funnel and mixing the phases again to form semistabilized dispersions; and (2) a dispersing agent-free oil-in-water dispersion, especially separating agent, cooling lubricant and/or plant protection agent, with a viscosity of less as 10000 mPas, preferably less than 1000 mPas, consisting of at least a first aqueous phase and at least a further immiscible phase, manufactured using the process;

Description

The present invention relates to a method for producing dispersant-free medium and low viscosity oil-in-water dispersions, with one Process-available oil-in-water dispersions and their use.

Medium and low viscosity oil-in-water dispersions are found in many industrial Areas of application, e.g. as a release agent in the construction industry e.g. to the Stripping of cast concrete, in the metal industry in the die casting process, in forging or the pharmaceutical industry in manufacturing of tablets and dragees, as cooling lubricants in metal cutting, i.e. when drilling, turning, milling or the like, or as a crop protection agent. While release agents and cooling lubricants predominantly in Formulated as oil-in-water emulsions are plant protection products depending on the active ingredients mainly as solid-liquid dispersions or emulsions applied.

For stabilization, dispersants are added to the dispersions, which reduce the interfacial tension between the individual phases in order to avoid segregation of the phases over a longer period of time and such a microscopic fine distribution of the dispersed phase (s) in the continuous Maintain phase over a longer period of time. The The proportion of dispersant depends on the specific application and is in conventional crop protection products up to 20% by weight. Commercial concrete release agents and cooling lubricants contain up to 30% by weight of emulsifiers.

The dispersants or emulsifiers previously considered necessary have application-related disadvantages, which even by adding more suitable Auxiliaries can often only be partially compensated for. In the Use of concrete release agents, for example, can emulsifiers because of them high interfacial affinity and interfacial activity an at least partial Emulsification of the separating agent / concrete body interface, causing a Part of the release agent penetrates into the concrete surface and closes after hardening leads to a correspondingly reduced surface quality of the concrete body. To at least partially compensate for these technical disadvantages is a considerable development effort for the selection and testing more suitable Auxiliaries necessary.

Another disadvantage of the dispersants or emulsifiers is that this reliable and sufficiently long stabilization only within one ensure a very narrow concentration and temperature range. On Exceeding or falling below the critical concentration limit values, for example Evaporation or by absorption of foreign substances as a result of improper use Storage, such as dilution of the dispersion with condensate or rainwater, leads as well as corresponding temperature jumps, especially those below freezing (freeze-thaw change), to an irreversible instability the dispersion or emulsion. Unless the instability is recognized and the dispersion is used in this form, inevitably leads to Loss of the processed products.

Furthermore, the dispersants or emulsifiers are due to the high proportion in the dispersions and not least because for the only selected applications, often especially for the application Synthetic dispersants or emulsifiers can be used, one represents a significant cost factor.

There has been no shortage of attempts in the past, the share of Dispersants or emulsifiers in dispersions or emulsions to reduce.

From DE 44 00 272 A1 a mold release agent for concrete is known which, as an oil component, possibly alongside other substances, preferably a water-immiscible and at temperatures between 5 and 15 ° C liquid, monofunctional C ₆ -C ₃₀ alcohol component contains an unsaturated C ₁₂ -C ₂₂ fatty alcohol, C ₁₆ -C ₂₈ guebert alcohol, C ₈ -C ₁₅ oxo alcohol or a saturated C ₆ -C ₁₀ alcohol. The emulsifiers used are preferably fatty acid monoglycerol esters or ethoxylates of fatty alcohols, of alkylphenols or of fatty acids, and particularly preferably sodium or potassium soaps of saturated and unsaturated C ₁₂ -C ₂₂ fatty acids. Due to the strongly emulsifying effect of these alcohols, stable emulsions should be obtained by adding comparatively small amounts of emulsifier. However, because of the use of emulsifiers, these concrete release agents also have the disadvantages described above.

DE 19911777 A1 describes a method for producing highly viscous cosmetic or pharmaceutical formulations, in which two or several liquid components immediately before using the formulation are mixed together from separate pantries by they are passed through a micromixer. By using the Micromixers aim to achieve a homogeneous distribution of all ingredients at extreme highly viscous formulations with a viscosity of 67,000 mPa.s without additives can be achieved by emulsifiers. However, this procedure also looks before, compositions with a viscosity of less than 50,000 add 2 to 50% by weight of emulsifiers, depending on the viscosity, being, in accordance with the physical principle, according to which the segregation immiscible phases with decreasing viscosity faster goes, more emulsifier are added with decreasing viscosity got to.

The object of the present invention is to provide a method, with the oil-in-water dispersions of medium to low viscosity, in particular Release agents, coolants and / or crop protection agents, without Addition of dispersant can be prepared, which, compared with the known dispersions of the same type, at least comparable, preferably have better application properties.

This object is inventively z. B. a method according to claim 1 solved.

Surprisingly, it was found that by just one intensive mixing of the dispersant-free medium and low viscosity phases Oil-in-water dispersions can be obtained, which themselves with - apart from the dispersant - the same composition as the previous one for the individual applications known dispersions for each Use sufficient homogeneity and also sufficient stability exhibit. The period of stability of the semi-stable dispersion according to the invention depends mainly on the quality and the degree of energy input the mixing and must be optimized for the respective application. Both for cooling lubricants during machining and for Manufacture of concrete release agents must have the appropriate energy input parameters When mixing, set so that the oil-in-water emulsion a stability of <10 seconds, corresponding to the time required for distributing and spreading release agent in the mold.

The dispersions are preferably prepared immediately before use. This ensures that the dispersion is the largest possible when used Has homogeneity.

Since with the process according to the invention dispersant-free dispersions can be obtained by adding the previously known oil-in-water dispersions usually to compensate for the application technology disadvantageous side effects of the dispersants added excipients become. Another advantage of the method according to the invention is that that only the organic phase has to be stored before use, since water is usually available at the place of use from water pipes stands. Furthermore, since the water and oil phases immediately before use can be brought together in defined volume ratios Exceeding or falling below the critical concentration limit values due to improper use Storage, for example by absorbing foreign substances or due to uneven evaporation of individual phases, no longer occur. Furthermore, in the process according to the invention, the previously used oil-in-water dispersions to prevent the growth of microorganisms mandatory addition of biocides or other preservatives for the most part or even entirely, because there is only one any aqueous phase or concentrate stored before use, which is diluted with tap water immediately before manufacture is, but not organic phase, in which an increase of microorganisms not taking place anyway, must be treated accordingly. Finally allows the method according to the invention, the ratio of the oil and water phase immediately before using the special conditions on site adapt flexibly, whereas in the case of the dispersions known hitherto corresponding ratio is inevitably predetermined by the emulsion.

The mixing of the at least two phases can be carried out on the person skilled in the art can be carried out in a known manner for this purpose, for example by injection one phase into the at least other phase, by turbulent mixing, by applying vibrations and cavitation such as ultrasound Homogenizers or other commercially available mixing devices.

As particularly suitable for this purpose, especially for the preparation of oil-in-water emulsions, static micromixers have proven to be like them e.g. are described in DE 199 28 123 A1, which are hereby introduced as a reference and is therefore considered part of the revelation. With these static micromixers the individual phases are defined by individual management channels Dimensions led and divided into a variety of liquid fins before the individual liquid lamellae with fragmentation of at least one of the Phases are merged. Allow these static micromixers a very high energy input during mixing, which makes it semi-stable Oil-in-water emulsions of comparatively long stability can be obtained can. On the other hand, these mixers ensure an even energy input, leading to high reproducibility with regard to homogeneity, the particle size distribution and the stability of the dispersions thus produced leads. The size distribution of the droplets forming the emulsified phase can be targeted to one by the flow velocity of the individual phases suitable value for the specific application.

The mixing of the at least two phases by membrane emulsification, as for example from Vladisavljevic, Goran T .; Tesch, Sabine and Schubert, Helmar in Chemical Engineering and Processing 2002, 41 (3), pp. 231-238 was hereby introduced as a reference and thus as part of the disclosure applies, has in particular for the production of oil-in-water emulsions proven to be workable. In membrane emulsification at least one phase to be dispersed through a microporous membrane, For example, a polypropylene membrane with a pore size of 0.4 µm, in the continuous Phase pressed. The droplet size of the dispersed phase as well the droplet size distribution depends in particular on the pretreatment of the Membrane and the pressure with which the phase to be dispersed through the Membrane is pressed off, even droplets with a lower Diameter than that of the membrane pores can be formed. According to the invention is based on the addition of emulsifiers, as previously provided was waived.

Also particularly suitable for mixing the at least two Phases have proven to be dynamic micromixers, e.g. in the DE 199 17 148 A1 are described, which is hereby introduced as a reference and is therefore considered part of the disclosure. With these micromixers, the fragmentation the at least one phase in the merging of the liquid lamellae additionally supported by mechanical vibrations. With such Micromixers can be the size distribution of the emulsified phase Droplets due to the flow speed of the individual phases, the frequency as well as intensity of the mechanical vibrations targeted at one for appropriate value can be set for the specific application.

In a further development of the inventive concept, it is proposed that the invention Carry out procedures in the form of a circular process. First semi-stable oil-in-water dispersions are produced as described above and fed to use. Then the dispersions collected and for the purpose of separating the individual phases, for example in one Separating funnel incubated before the at least two phases, if necessary after separation of impurities resulting from the application and possibly after Compensation for any liquid loss by means of metering pumps again the mixing device are supplied in which the phases become semi-stable with one another Dispersions are mixed.

Such a cycle process is particularly suitable for cooling and Lubrication in metal cutting, in which the oil-in-water emulsion only briefly comes into contact with the product to be processed and the contamination in the form of chips caused by the application can be separated particularly easily. Maybe with cooling lubrication Any liquid losses occurring in the individual phases can then occur the mixing can be easily compensated for by appropriate metering. Biocides or other preservatives only need to be aqueous Phase added as the growth of microorganisms in the organic Phase is inhibited anyway. In the case of disposal, only the organic one Treat phase as special chemical waste, as it is weak at best organically contaminated water phase can be eliminated in conventional sewage treatment plants can. So compared to the previously used stable emulsions considerable cost savings can be achieved.

Such a continuous process can also be used, for example, for release agents, especially in the pharmaceutical field in the manufacture of tablets and coated tablets. One skilled in the art immediately recognizes that such a continuous Process not on medium-sized and lower oil-in-water dispersions Viscosity is limited, but with any kind of dispersant-free Dispersions is feasible. Other examples are the production of cakes, Sweets, chocolates or gummy bears.

Another object of the present invention are dispersant-free Oil-in-water dispersions, in particular release agents, cooling lubricants and Plant protection products which can be obtained by the process according to the invention.

Apart from the dispersants, the oil-in-water dispersions according to the invention can with regard to the ingredients and the proportions of Ingredients have the same composition as the previously known stable oil-in-water dispersions of the same type. However, the in many known oil-in-water dispersions to compensate for the negative application effects of the dispersants added to be dispensed with. There is also an addition of biocides or preservatives only required if the aqueous phase or an equivalent Concentrate over the preparation of the semi-stable dispersion is stored for a longer period of time or if the semi-stable dispersion over a to be used several times over a longer period of time.

The release agents according to the invention can, for example, be mineral oils, White oils, waxes, triglycerides, esters from aliphatic carboxylic acids and one or polyhydric alcohols, alcohols or ethers or a mixture of two or more substances from one or more of the aforementioned Groups included. The ratio of the aqueous to the organic phase is preferably between 20: 1 and 1: 1.

The release agents according to the invention particularly preferably contain an oil phase a mixture of 90 to 98% by weight of a base oil, 0 to 10% by weight of one separating components, 0.2 to 1 wt .-% of an anti-corrosion additive and 0.2 to 5% by weight of a wetting agent. Are particularly suitable as base oil Hydrocarbons, triglyceride mixtures, esters, very particularly preferred Esters of a carboxylic acid with more than 16 carbon atoms and an alcohol component with more than 8 carbon atoms, fatty alcohols and a mixture of two or more substances from one or more of the aforementioned groups. Examples of separating components are Mixtures of fat and resin acids, triglyceride mixtures, esters and polyol alcohol derivatives as well as their mixtures. As a corrosion protection additive are merely For example, succinic acid esters, amine phosphates, sulfonate / carboxylate mixtures, Imidazole derivatives, N-oleyl sarcosine and phosphoric acid esters, which are used both alone and in combination can. Suitable wetting agents are fatty acid polyethylene glycol esters, sodium diisooctyl sulfosuccinate, Sorbitan trioleate, glycerol monooleate, glycerol dioleate, Alcohol derivatives, ester derivatives and silicone additives, which both alone and can also be used in combination.

Cooling lubricants according to the present invention can e.g. as organic Phase a mixture of 5 to 80 wt .-% base oil, 5 to 20 wt .-% corrosion protection additives as well as metal inhibitors, possibly preservatives and contain other common additives. Suitable base oils are ester oils, paraffinic or naphthenic hydrocarbons, alcohols, ethers, polyisobutenes, Polyalkylene glycols and mixtures of two or more substances one or more of the groups listed above. As corrosion protection additives come in particular phosphoric acid esters, triazoles, thiadiazoles, Reaction products of boric acid with primary or tertiary alkanolamines, Fatty acids, fatty acid alkanolamines or mixtures of two or more Substances from one or more of the groups listed above into consideration. The oil phase can also alkylsuccinimides, castoroil ethoxylates, Petroleum sulfonates, solid lubricants, toluyltriazoles, defoamers and / or Anti-fog additives included as other common additives. The proportion of the oil phase can in the cooling lubricant according to the invention between 2 and 25 % By weight.

The crop protection agents according to the invention can in principle be all common agrochemical active ingredients, such as herbicides, pesticides, insecticides, acaricides, algicides Aphicides, bactericides and virucides. Are only exemplary Active substances such as D, L- and L-phosphinothricin ammonium, D, L- and D-fenoxapropethyl, Diclofopmethyl, ethofumesate, phenmedipham and desmediphan called. In addition to the active ingredients, the plant protection products further customary additives, such as inert substances, fillers or anti-foaming agents, be inflicted. Depending on the active ingredient, the present invention Plant protection products in the form of oil-in-water emulsions or in the form of solid / liquid oil-in-water dispersions.

a) Die Verwendung des erfindungsgemäßen Trennmittels für das Formtrennen eines hydraulischen Bindemittels, bspw. Beton,

b) die Verwendung des erfindungsgemäßen Kühlschmierstoffs bei der spanenden Bearbeitung von Metallen,

c) die Verwendung der erfindungsgemäßen Öl-in-Wasser-Dispersion als Trennmittel beim Schmieden,

d) die Verwendung der erfindungsgemäßen Öl-in-Wasser-Dispersion in der Nahrungs- und Genussmittelindustrie, bspw. zur Herstellung von Kuchen, Bonbons, Pralinen, Gummibären oder dergl.,

e) die Verwendung der erfindungsgemäßen Öl-in-Wasser-Dispersion bei der Herstellung von Autoreifen, von Polymeren oder polymerhaltigen Zusammensetzungen, bspw. von Gleitlacken und Gleitfilmen.

Preferred applications of the oil-in-water dispersions according to the invention are:

a) the use of the release agent according to the invention for the mold release of a hydraulic binder, for example concrete,

b) the use of the cooling lubricant according to the invention in the machining of metals,

c) the use of the oil-in-water dispersion according to the invention as a release agent in forging,

d) the use of the oil-in-water dispersion according to the invention in the food and beverage industry, for example for the production of cakes, candies, chocolates, gummy bears or the like,

e) the use of the oil-in-water dispersion according to the invention in the manufacture of car tires, of polymers or polymer-containing compositions, for example of lubricating varnishes and lubricating films.

Examples

The invention is explained below with reference to Examples 1 to 3. This Explanations are only exemplary and limit the general idea of the invention not a.

example 1

To produce a concrete release agent formulation according to the invention in the form of an oil-in-water emulsions, an oil phase was first prepared from the following components: 90% by weight spindle oil 5% by weight rapeseed oil 3% by weight oleic acid 0.5% by weight Bernsteinsäureester 0.5% by weight Fettsäurepolyethylenglykolester

A static micromixer, as described in Example 1, was then used DE 199 28 123 A1 describes the oil phase with one to one with water Oil-in-water emulsion mixed with an oil content of 5.5% by weight.

The viscosity of the oil phase, the viscosity of the emulsion and the average Diameter of the oil droplets is shown in Table 1.

Example 2

To produce a concrete release agent formulation according to the invention in the form of an oil-in-water emulsions, an oil phase was first prepared from the following components: 98% by weight rapeseed oil 1% by weight AdditinRC 4820 (commercial product) 1% by weight Isooctylsulfosuccinat

The oil phase was then added with water as described in Example 1 one mixed into an oil-in-water emulsion with an oil content of 13.3% by weight.

The viscosity of the oil phase, the viscosity of the emulsion and the average Diameter of the oil droplets is shown in Table 1.

Example 3

To produce a concrete release agent formulation according to the invention in the form of an oil-in-water emulsions, an oil phase was first prepared from the following components: 91.2% by weight Isooctyloleat 5% by weight oleic acid 0.8% by weight AdditinRC 4220 (commercial product 9 3% by weight glycerol oleate

The oil phase was then added with water as described in Example 1 one mixed to form an oil-in-water emulsion with an oil content of 24.4% by weight.

The viscosity of the oil phase, the viscosity of the emulsion and the mean diameter of the oil droplets are shown in Table 1. example 1 2 3 Viscosity (20 ° C) oil phase (mm ² / s) 17.1 15.0 39.7 Viscosity (20 ° C) emulsion (mm ² / s) 7.1 3.1 2.4 Volume distribution: Average diameter (µm) 6.67 7.62 6.74

All of the above oil-in-water emulsions have been used successfully as parting agents in the Demoulding of concrete bodies used. All emulsions had one long stability and excellent application properties.

Claims (19)

Process for producing a dispersant-free oil-in-water dispersion, especially for the production of a release agent, a cooling lubricant and / or a crop protection agent with a viscosity of less than 10,000 mPas, preferably less than 5,000 mPas, especially preferably less than 1,000 mPa · s, consisting of at least a first im Substantially aqueous phase and at least one other with the first immiscible phase by combining the at least two phases and without the addition of a dispersant by the introduction of energy in this way mixed intensively, that a stable dispersion for at least 5 seconds receives. A method according to claim 1, characterized in that the at least two phases are brought together and mixed only immediately before the dispersion is used. Method according to one of the preceding claims, characterized in that the aqueous phase is prepared by diluting a concentrate with water before it is mixed with the at least one further phase. Method according to one of the preceding claims, characterized in that the at least two phases are mixed by injecting one phase into the at least other phase, by turbulent mixing, by applying vibrations and cavitation, such as ultrasound, or by means of homogenizers. Method according to one of the preceding claims, characterized in that the at least two phases are mixed by means of a static or a dynamic micromixer. A method in particular for the preparation of a dispersant-free oil-in-water emulsion according to one of the preceding claims, characterized in that the at least two phases are mixed by means of a micromixer, the individual phases being guided through individual guide channels of defined dimensioning and divided into a plurality of liquid lamellae before the individual liquid lamellae are brought together with fragmentation of at least one of the phases. A method according to claim 6, characterized in that the fragmentation of the at least one phase is additionally supported by mechanical vibrations when the liquid lamellae are brought together. Process for the continuous production of a dispersant-free Dispersion, in particular for the continuous production of a release agent or a cooling lubricant, from at least two immiscible with each other Phases by first merging the at least two phases and without the addition of a dispersant by the introduction of energy in this way mixed intensively, that a stable dispersion for at least 5 seconds receives, then the dispersion of the application, thereby the dispersion fields and for the purpose of separating the individual phases, for example in one Separate funnel before incubating the at least two phases together mixed to form semi-stable dispersions. A method according to claim 8, characterized in that after the dispersion has been collected and before the at least two phases have been mixed again, impurities resulting from the application are separated from the dispersion or from the separated phases of the dispersion. Method according to claim 8 or 9, characterized in that after the dispersion has been collected and before the at least two phases have been mixed again, liquid losses suffered as a result of the use are compensated for by metering in. Dispersion-free oil-in-water dispersion, especially release agents, Cooling lubricant and / or crop protection agents with a viscosity of less than 10,000 mPa · s, preferably less than 5,000 mPa · s, particularly preferred less than 1,000 mPa · s consisting of at least a first substantially aqueous phase and at least one other with the first not miscible phase, produced by a method according to one of the claims 1 to 10. Release agent as a water-in-oil emulsion, produced by a process according to one of claims 1 to 10, characterized in that it contains mineral oils, white oils, waxes, triglycerides, esters of aliphatic carboxylic acids and mono- or polyhydric alcohols, alcohols or as the oil phase Contain ether or a mixture of two or more substances from one or more of the aforementioned groups. Cooling lubricant as a water-in-oil emulsion, produced by a process according to one of Claims 1 to 10, characterized in that it is a mixture of 5 to 80% by weight of base oil and 5 to 20% by weight of corrosion protection additives as the organic phase as well as metal inhibitors, possibly preservatives and other common additives. Plant protection product as an oil-in-water dispersion, produced by a process according to one of claims 1 to 10, characterized in that it contains agrochemical active ingredients, such as herbicides, pesticides, insecticides, acaricides, algicides, aphicides, bactericides and virucides, and further conventional additives , such as inert substances, fillers or anti-foaming agents. Plant protection products as an oil-in-water dispersion according to Claim 14, characterized in that they contain D, L- and L-phosphinothricin ammonium, D, L- and D-fenoxapropethyl, diclofopmethyl, ethofumesate, phenmedipham and desmediphan as active ingredients. Use of a water-in-oil emulsion according to claim 12 for the Mold separation of a hydraulic binder material, e.g. concrete. Use of a cooling lubricant composition according to claim 13 when machining metals. Use of a water-in-oil emulsion according to claim 12 as Release agent when forging. Use of a water-in-oil emulsion according to claim 12 as Release agent in the production of cakes, candies, chocolates or gummy bears.