Invention Concerning Agricultural Active Substances

• US 20080213590A1
• Filed: 05/30/2005
• Published: 09/04/2008
• Est. Priority Date: 05/28/2004
• Status: Active Grant

• Current Assignee: Justus-Liebig-Universitaet Giessen, Philipps-Universität Marburg
• Original Assignee: Justus-Liebig-Universitaet Giessen, Philipps-Universität Marburg
• Inventors: Wendorff, Joachim H., Greiner, Andreas, Hummel, Hans E., Becker, Matthias, Dersch, Ronald
• Granted Patent: US 8,017,061 B2
• Time in Patent Office: Days
• US Class Current: 428/401
• CPC Class Codes: A01M 7/00 Special adaptations or arrangements of liquid-spraying apparatus for purposes covered by this subclass
• CPC Class Codes: A01N 25/10 Macromolecular compounds
• CPC Class Codes: A01N 25/34 Shaped forms, e.g. sheets, not provided for in any other sub-group of this main group
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: D01D 5/0084 Coating by electro-spinning, i.e. the electro-spun fibres are not removed from the collecting device but remain integral with it, e.g. coating of prostheses
• CPC Class Codes: D01D 5/0092 characterised by the electrical field, e.g. combined with a magnetic fields, using biased or alternating fields
• CPC Class Codes: D01D 5/34 Core-skin structure; Spinnerette packs therefor
• CPC Class Codes: Y10T 428/298 Physical dimension

Abstract

The invention relates to supports consisting of nanoscalar polymer fibres, polymer tubes or hollow fibres for the application and targeted and/or delayed release of ingredients, in particular, agricultural active ingredients. The invention also relates to a method and a device for the production of supports of this type in a charged or empty state. The method and device use electrospinning technology.

Claims

1. Use of nanoscaled polymer fibers, polymer tubes or nanoscaled hollow fibers with and/or without nanoscaled morphologies as carriers for agricultural or agriculturally useful active substances, wherein the fibers or tubes feature a diameter of 10 nm to 6 μ

m and are biodegradable, i.e. are degradable under natural environmental conditions.

2. Use according to claim 1, wherein the fibers or tubes feature a surface of 100 to 700 m²/g.

3. Use according to claim 1, wherein the release of the active substances out of or from the fibers or out of or from the tubes occurs through degradation of the fibers through diffusion or/and permeation.

4. Method for the output of nanoscaled polymer fibers and tubes or hollow fibers as carriers for agricultural or agriculturally useful active substances, said carriers being in a state loaded or unloaded with such active substances, wherein the output occurs through use of the procedure of electrospinning.

5. Method according to claim 4, wherein the farmland or/and plants found thereon or/and seeds found thereon or therein, or seeds without surrounding soil are used as counter electrodes.

6. Method according to claim 4, wherein the output occurs through relative movement of the counter electrode to the electrospinning device according to the present invention.

7. Method according to claim 4, wherein, along with the farmland or/and the plants, or/and a seed, a counter electrode connected mechanically or/and electrically to the electrospinning device is used.

8. Method according to claim 4, wherein the active substance is blended or mixed with the polymer which is to be spun.

9. Method according to claim 4, wherein, for the coating or covering of a first core fiber parallel to the electrospinning procedure for the production of this core fiber, a second or further electrospinning procedure for the production of the first or further coating/s or covering/s is carried out.

10. Method according to claim 9, wherein, for the execution of the method, the second or further nozzles providing a first or further coating(s) are set at the same electric potential as the first nozzle which serves for output of the first fiber.

11. Method according to claim 9, wherein, for the execution of the method, the second or further nozzles for the output of a first or further coating(s)/covering(s) are set at another electric potential than the first nozzle which serves for output of the first fiber, so that the first, i.e. the core-fiber is used as the first counter electrode for the second or further nozzle(s) serving for the coating or covering.

12. Method according to claim 4, wherein, for the increase of the plaiting of the target surface(s) by the fibers, a relative movement of the nozzle(s) in the relative direction of movement between nozzle and target surface, e.g. via a rotation of the nozzle(s), is realized.

13. Method according to claim 12, wherein, for the further increase of the plaiting of the target surface(s) by the fibers, an alternating voltage field is created between the first electrode, in the form of the nozzle(s), and the counter electrode, in the form of farmland, plant(s) or seed(s).

14. Device for the execution of the method according to claim 4, wherein the device features an electrospinning device with an energy source and a nozzle electrically connected therewith, so that, for the passage of the mixture of polymer and active substances to be spun (in the form of a solution or a melt), the nozzle is set at a different electric potential than the target surface of the mixture of polymer and active substances which forms the counter electrode.

15. Device according to claim 14, wherein the device is realized to be able to be moved relative to a farmland.

16. Device according to claim 14, wherein the device features, along with the target surfaces, further counter electrodes, for instance in the form of preferably metallic counter electrodes arranged next to the target surfaces.

17. Device according to claim 14, wherein the device features sensors, for instance optic sensors for ascertainment of the type or/and the state of the target surfaces, which are realized in a manner connected to means of comparison of the device, of such a type that only upon positive recognition of the type or/and the state of the target surface initiates the method for the “

spinning or webbing”

of the target surface.

18. Device according to claim 14, wherein the device features, along with the first nozzle for the release of a carrier-fiber, further nozzles for the delivery of coatings or coverings made of polymers, wherein the further nozzles feature the same or a different electric potential as the first nozzle, so that co-electrospinning is made possible.

19. Device according to claim 14, wherein the device features means for the ascertainment of the released carrier- or/and active substance mass or -speed, which are preferably realized to be connected with likewise provided means for the control of the output-mass or -speed.

20. Device according to claim 14, wherein the device features means for the blending or mixing of the polymers with the active substances, as well as, in the case of significantly changing working conditions (temperature, humidity etc.), featuring further means for tempering or supplying water to the polymer and/or active substances.

21. Device according to claim 14, wherein the device features means for coating in the form of means of a polymer fiber after emanating the blending or mixing of the polymers with the active substances, as well as, in the case of significantly changing working conditions (temperature, humidity etc.), featuring further means for tempering or supplying water to the polymers and/or agents.

22. Method for the coating of target surfaces in the form of dielectric substances or ferroelectric crystals, preferably of bodies containing water with nanoscaled fibers, wherein the target surfaces are exposed to an electric potential and, thus, an electric field and, emanating from a nozzle, which is set at a higher electric potential than the target surface, a solution or melt containing a polymer is delivered to the target surface.