DE10064638A1 - Silicate particles - Google Patents

Abstract

The invention relates to a method for loading a siliceous material, whereby the siliceous material is used as a carrier for low-viscosity to high-viscosity liquids and solids. The inventive method is characterised in that said siliceous material contains hollow bodies.

Description

The invention relates to a method for loading a silicate material which is the silicate material as a carrier for low-viscosity to high-viscosity Substances and / or solids is used.

A silicate material means all non-crystalline materials, which have a small grain size and usually in the range between 20 microns up to less than 10 nm. Silicate material usually has a glass-like Structure, but crystalline sections can also occur. The In addition to silicon dioxide, silicate material can contain other elements such as boron, Aluminum, alkali, alkaline earth metals or metals of the sub-group elements contain. In addition, the silicate material can be partially hydrated Form. Silicate materials have a wide range of applications, primarily as fillers / additives for plastics (POTTERS-BALLOTINI).

In many areas of application, materials with additives, so-called additives offset to achieve additional positive properties that the Does not own the starting product. Individual additives or one Combination of multiple additives can be used to achieve the desired result achieve. These additives can be completely different in nature such as. B. Fragrances, corrosion inhibitors, fungicides, bactericides. From a combination of various active substances, the problem that the Active ingredient combination in the finished product is not long-term stable, d. H. it can too  an accelerated breakdown of one or more of the active ingredients due to their Interact with each other. To avoid this unwanted degradation may need to prevent another combination with possibly reduced effect can be used. Furthermore, it can be in the Incorporation of such additives into the finished product for mixing problems come.

In addition, there is the problem that the rate of release of the additive normally only through the diffusion rate in the Starting product is given. It is difficult to influence, so not the desired additive can always be used with every starting product, because it either doesn't release at all or releases too quickly. This will either solved by an increased use of additives, or by using a other additives. The increased use is on the one hand with increased raw material costs connected and can, because of the increased additive concentration, due to it prohibit possible harm to health.

The object of the present invention is to provide a dosage form for various To create additives that enable a controlled release of active ingredients.

The invention is based on the knowledge that the possible uses and the Effectiveness of liquid or solid additives can be increased if they are bound to a silicate material via absorption and / or adsorption.

The invention relates to a method for loading a silicate Material in which the silicate material as a carrier for low-viscosity up highly viscous liquids and / or solids is used, which is characterized is that the silicate material contains hollow bodies.

Another object of the invention is the use of a silicate Material containing hollow bodies as a carrier for low-viscosity to high-viscosity Liquids and / or solids.  

The method according to the invention for loading a silicate delivers systems which are characterized by the fact that an active ingredient over a desired period of time can be released slowly (so-called "slow-release" effect). The basis for the release rate it is primarily from the silicate Carrier material determines and can be influenced. So can about the choice of Carrier material actively influences the rate of diffusion of the adsorbed / absorbed Active ingredient are taken.

Another advantage of the method according to the invention is that this also Active ingredients can be incorporated into the starting product that deal with this don't normally let it mix. In addition, ad- and / or absorbed active ingredients used in the starting product have a diffusion coefficient that is too large and therefore released too quickly become. As a result, substances of application that are available with previously are accessible known methods due to their diffusion behavior in the starting products could not be used, although z. T. better drug properties have. The delivery speed can be particularly advantageous by adjusting a suitable coating ("coating") before and / or after loading the silicate particles can be influenced so that the desired Dispensing speed is reached. So when adding a fungicide loaded silicate material into a joint sealant an extrapolated Delivery time of more than 24 months can be set. When using silicate particles loaded with insecticide in or as a crop protection powder dispensing of the active ingredient over a period of one week can be stopped. According to the previously known methods, the active ingredient could be released via a longer period can only be achieved by adding a larger amount of active ingredient become. This is no longer necessary in the method according to the invention.

The purpose of the method according to the invention is to absorb and / or absorb Drug at a later time at a desired rate to release again. The carrier material can be removed and / or Adsorbent for a water-based liquid, emulsion or Microemulsion, a fragrance, a gel, an oil, an organic or inorganic  Fat, a corrosion inhibitor, a liquid or solid fertilizer, a herbicide, Fungicide, insecticide, bactericide or virucide, or a mixture thereof.

The use of spherical silicate bodies is particularly advantageous Structure, as opposed to mechanical stability in this embodiment external pressure is best. Furthermore, the internal friction and thus the abrasion low when transferring the loaded carrier with this geometry.

According to a particularly preferred embodiment of the invention The silicate material contains largely closed hollow bodies. This is particularly advantageous since partially closed hollow bodies become easier let loaded. Loading is carried out when the hollow bodies are completely closed via diffusion through the cave body wall.

According to a further preferred embodiment, the silicate Materials have a diameter of less than 20 µm, in particular less than 1 µm. According to a particularly preferred embodiment, silicate particles are also less than 100 nm, in particular less than 10 nm used for the loading. As a rule, the wall thickness does not remain constant here, but is one Function of the particle diameter, but not directly proportional to it dependent. The dependence of particle diameter on wall thickness is also influenced by the manufacturing process of the silicate material. Have so Larger particles with a diameter of approx. 50 µm usually have a wall thickness of approx. 1 µm and smaller particles of about 1 µm have a wall thickness of about 0.1 µm. The specified particle sizes refer to the diameter of the individual Particles.

According to a preferred embodiment, silicate material is used that is at least partially agglomerated. This is particularly advantageous because it means that Grain of the material can be tailored to the application. Becomes when using a fine-grained material required such. B. a powder Fungicide, a silicate material with only a low degree of agglomeration or used without agglomeration. If a coarser material is desired e.g. B. for  Use as an insect bait is at least partially agglomerated Material is an advantage.

A particularly preferred embodiment of the method according to the invention is the loading of hollow micro glass spheres as a silicate carrier material. Such Micro glass hollow spheres are normally used as an additive in plastics used. It is of particular advantage that the microglass hollow spheres are commercial are available and have the required structural features.

According to a further preferred embodiment, the silicate material comprises filter ash (also called fly ash) which is obtained during combustion in hard coal-fired power plants. The filter ash, which is generated at combustion temperatures below 1300 ° C, is particularly suitable here, since this material has better adsorption and absorption properties. The use of filter ash is particularly advantageous because this product is inexpensive to purchase. The silicate portion is primarily in the form of small hollow spheres of glass-like modification. The aluminum oxide / hydroxide, calcium oxide / hydroxide and iron oxide / hydroxide particles also contained in the filter ash also act as an absorbent / adsorbent. The silicate portion does not necessarily have to be pure SiO ₂ , but it may contain iron, calcium and aluminum and other ions. The oxides or hydroxides of aluminum, iron and calcium do not have to be present in pure form next to one another as pure phases, but can certainly form mixtures at the crystalline level.

The carrier materials described are particularly suitable for loading with Active substances, since they adsorb and / or absorb them. The active ingredients can be low to highly viscous liquids or even solids. This Liquids or solids can be a water-based liquid, a Emulsion or microemulsion, a dispersion, a fragrance, a gel, an oil, a organic or inorganic fat, a corrosion inhibitor, a liquid or solid fertilizer, a herbicide, fungicide, insecticide, bactericide or virucide or one Be a mixture of them.  

If the active ingredients with which the carrier is to be loaded, increased pressure and / or withstand temperature, it is advantageous to vary the loading perform these parameters, e.g. B. the viscosity of a liquid in the Reduce load. But it is also possible to reduce the load To perform pressure. Here, pressures of 0.1 to 200, preferably 1 to 100 bar and particularly preferably 1 to 50 bar and temperatures of 5 to 400 ° C, preferably 20 to 300 ° C and particularly preferably 50 to 200 ° C used. On the other hand, the adsorption capacity of the Reduce wearer, so a combination of increased pressure and increased Temperature is of particular advantage. So the loading of a silicate Carrier material with Cetiol OE at 150 ° C and 50 bar pressure much faster be performed as under normal conditions.

According to a further preferred embodiment, the carrier is first one Exposed to negative pressure, e.g. B. to adsorbed substances such as gases or First remove water. The next step is the loading carried out. It is advantageous that the active ingredient is no longer already adsorbed Substances must displace, which improves the adsorption behavior.

For loading with solids, it is particularly advantageous to start with a suitable solvent, then apply to the carrier and then remove the solvent again. The removal of the solvent can z. B. done by spray drying to agglomerate the To prevent particles. This procedure can also be used for advance wedge for the Loading with liquids z. B. with the help of an emulsifier.

According to a particularly preferred embodiment of the invention The carrier is subjected to a pretreatment prior to loading accelerates the adsorption and / or absorption behavior and / or increases the capacity. So z. B. an activation by briefly etching the silicate material with dilute acid, e.g. As hydrofluoric acid, to roughen the Particle surface and an increase in the number of capillaries. The  The increase in surface area caused by roughening primarily results in a Increased capacity for adsorption and the increase in the number of capillaries increased essentially the rate of absorption, with the additional Capillary walls also have a positive effect on the adsorption behavior.

According to a further preferred embodiment, the silicate carrier is before and / or encapsulated after loading. Here, an encapsulation before Loading can be used to agglomerate the particles in the loading step to prevent. This is particularly advantageous if, on the one hand, the encapsulation Ad and / or absorption under the selected parameters for pressure and temperature not significantly impaired during loading and the one used for loading Active ingredient is very sticky or highly viscous. Such encapsulation can also be used the loading can be carried out, e.g. B. a slower, delayed To achieve release (so-called "slow-release") of the adsorbed / absorbed active ingredients. The encapsulation prevents the active ingredient from being released immediately and thus enables release over a certain period of time. So can when adding silicate material loaded with a fungicide into a Joint sealing compound has an estimated delivery time of more than 24 months can be set. When using silicate-laden insecticide Particles in or as a crop protection powder can release the active ingredient the period of one week can be set. B. a Polymer, a wax, a melamine resin, polyacrylic acid, alginate, gelatin, starch, Dextrins or polyvinyl alcohol can be used. When encapsulating with Polymers can be the polymer z. B. from a solution, or by polymerization can be applied directly to the particle surface.

According to a further preferred embodiment of the invention The process involves a multi-layer encapsulation, the above mentioned effects can be distributed to the individual layers. So z. B. there is also an encapsulation step before the loading, which reduces the pourability of the Product improves and prevents sticking; one after loading encapsulation leads to a controlled release of active ingredient. Further  Layers can also be applied to the product before Humidity u. to protect external influences.

Another object of the invention is the use of a silicate Material containing hollow bodies as a carrier for low-viscosity to high-viscosity Liquids and / or solids. The carrier can be used for absorption and / or Adsorption of a water-based liquid, an emulsion or microemulsion, a dispersion, a fragrance, a gel, an oil, an organic or inorganic grease, a corrosion inhibitor, a liquid or solid Fertilizer, a herbicide, fungicide, insecticide, bactericide or virucide or one Mixture of them. The one loaded with one or more active ingredients silicate carrier is then introduced into an end product. Furthermore you can two or more silicate carriers loaded with different active ingredients in one Product can be used. This is particularly advantageous if the active ingredients used in the direct introduction into the starting product are long-term stable, e.g. B. because they accelerate the decomposition among themselves. Since the Active ingredients are bound to the carrier material and not in free form side by side, a mutual decomposition process becomes largely avoided.

Another object of the invention is the use of filter ash as Carrier for low-viscosity to high-viscosity liquids and solids. Fly ash contains a high proportion of iron, calcium and aluminum oxides silicate material. This is particularly advantageous because filter ash has very good ad and shows absorption properties and is an inexpensive carrier material.

Examples 1 Loading filter ash with a liquid and then encapsulating it

500 ml of olive oil are mixed with 100 g of a filter ash. The particles are for stirred for an hour and soaked in the oil. The saturated particles will filtered off and by briefly washing with acetone from the excess olive oil freed. The powder obtained is saturated with an alkaline Dispersed polyacrylic acid solution and encapsulated by spray drying.  

Example 2 Loading filter ash with a liquid under increased pressure and temperature

500 ml of Cetiol OE are mixed with 100 g of filter ash and added for five hours Stirred 150 ° C at 50 bar pressure and soaked with the oil. The particles so loaded are then filtered off and briefly washed with acetone in order to Remove excess cetiol from the surface. This makes it a pourable Obtain powder containing Cetiol OE.

Example 3 Loading filter ash with a solid after loosening it beforehand

500 ml solution of a 0.1 mol / l Fosetyl Al (aluminum tris (ethyl phosphite)) in water is mixed with 100 g of filter ash and stirred for one hour. The saturated Particles are filtered off and then spray dried. As a result, with Receive Fosetyl Al partially filled filter ash.

Example 4 Loading filter ash with a liquid followed by slow Release ("slow-release")

100 ml of perfume oil are mixed with 100 g of a filter ash. The particles are for stirred for an hour and soaked in the oil. Give the saturated particles then, even at higher temperatures such. B. 40 ° C, the perfume oil delays free. Even after 6 weeks at 40 ° C, the fragrance of the perfume oil is still there clearly perceivable.

Claims (22)

1. A method for loading a silicate material, in which the silicate material serves as a carrier for low-viscosity to high-viscosity liquids and / or solids, characterized in that the silicate material contains hollow bodies. 2. The method according to claim 1, characterized in that the silicate Material contains spherical hollow body. 3. The method according to claim 1 or 2, characterized in that the contains silicate material largely closed hollow body. 4. The method according to any one of the preceding claims, characterized in that the silicate material has a glass-like structure. 5. The method according to any one of the preceding claims, characterized in that the average particle diameter is smaller than 20 µm, in particular smaller than 1 µm. 6. The method according to claim 5, characterized in that the middle Particle diameter is less than 100 nm, in particular less than 10 nm. 7. The method according to any one of the preceding claims, characterized in that that the silicate material comprises hollow glass microspheres. 8. The method according to any one of claims 1 to 6, characterized in that the includes silicate filter ash material. 9. The method according to claim 8, characterized in that the filter ash at Temperatures below 1300 ° C, especially below 1200 ° C has been. 10. The method according to claim 8 or 9, characterized in that the filter ash contains ferromagnetic iron oxide and / or iron hydroxide particles.   11. The method according to any one of claims 8 to 10, characterized in that the Contains filter ash calcium oxide and / or calcium hydroxide. 12. The method according to any one of claims 8 to 11, characterized in that the Contains filter ash aluminum oxide and / or aluminum hydroxide. 13. The method according to any one of the preceding claims, characterized in that the carrier is a water-based liquid, an emulsion or Microemulsion, a dispersion, a fragrance, a gel, an oil, an organic or inorganic fat, a corrosion inhibitor, a liquid or solid Fertilizer, a herbicide, fungicide, insecticide, bactericide or virucide or one Mixture thereof is absorbed and / or adsorbed. 14. The method according to any one of the preceding claims, characterized in that the loading with the help of increased pressure and / or Temperature. 15. The method according to any one of claims 1 to 13, characterized in that the Loading with the help of reduced pressure and / or temperature he follows. 16. The method according to any one of the preceding claims, characterized in that the loading with the help of a solvent and / or a Emulsifier takes place. 17. The method according to any one of the preceding claims, characterized in that that the carrier before loading to improve the absorption and / or Adsorption behavior is subjected to a pretreatment, in particular hydrophobized, hydrophilized or activated. 18. The method according to any one of the preceding claims, characterized in that that the carrier is encapsulated before or after loading, especially with a polymer, a wax, a melamine resin, polyacrylic acid, alginate, Gelatin, starch, dextrins and / or polyvinyl alcohol.   19. Use of a silicate material containing hollow bodies as a carrier for low-viscosity to high-viscosity liquids and / or solids. 20. Use of filter ash as a carrier for low-viscosity to high-viscosity Liquids and / or solids. 21. Encapsulation of a silicate carrier material for use in one Method according to one of claims 1 to 17, wherein the encapsulation before and / or after loading. 22. Encapsulated silicate carrier material, producible according to claim 21.