Droplet ejector having treated surface - Patents.com
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-03-09
- Publication Date
- 2026-03-16
Abstract
Description
[Technical field]
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Provisional Patent Application No. 63 / 318,202, entitled "DROPLET EJECTOR WITH OLEOPHOBIC COATING", filed March 9, 2022, Provisional Patent Application No. 63 / 323,770, entitled "ROUGHENED DROPLET EJECTOR SURFACE AND COATINGS", filed March 25, 2022, and Provisional Patent Application No. 63 / 346,794, entitled "POLYMER DROPLET EJECTOR WITH SPUTTERED COATING SURFACE", filed May 27, 2022, all of which are incorporated by reference in their entireties herein.
[0002] This disclosure relates to droplet generating devices that generate aerosols of compositions for inhalation, such as by the mouth and nose. [Background technology]
[0003]
[0003] The use of droplet generating devices to deliver substances to the respiratory system is an area of great interest. A major challenge is to provide a device that delivers a precise, consistent and verifiable amount of a substance in a droplet size suitable for successful delivery of the substance to a target area of the respiratory system.
[0004]
[0004] A droplet delivery device includes an ejector mechanism having a mesh, perforated plate, or similar substrate with holes of a desired size to produce a desired surface contact angle, and a powered transducer acts on the liquid and the ejector mechanism to produce droplets from the liquid passing through the mesh. In some devices, the powered transducer may vibrate a membrane to push the liquid through the mesh to produce droplets ("push mode"), while in other devices the transducer may be coupled to vibrate the mesh directly to produce droplets. Examples of devices including such ejector mechanisms using substrates having holes are described in U.S. Patent Application Publication No. US2022 / 0401661, published on December 22, 2022, entitled "DELIVERY DEVICE WITH PUSH EJECTION," International Publication No. WO2020 / 264501, published on December 30, 2020, entitled "DELIVERY OF SMALL DROPLETS TO THE RESPIRATORY SYSTEM VIA ELECTRONIC BREATH ACTUATED DROPLET DELIVERY DEVICE," and International Publication No. WO2020 / 264501, published on November 12, 2020, entitled "ULTRASONIC BREATH ACTUATED RESPIRATORY DROPLET DELIVERY DEVICE AND METHODS OF and US Pat. No. WO 2020 / 227717, entitled "USE," all of which are incorporated by reference in their entireties, including the incorporation of such publications and patent applications as cited, incorporated by reference, or relying on the disclosures referenced. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] U.S. Patent Application Publication US2022 / 0401661 [Patent Document 2] WO2020 / 264501 [Patent Document 3] WO2020 / 227717 Summary of the Invention [Problem to be solved by the invention]
[0006]
[0005] Droplet delivery devices can be used to facilitate inhalation of a number of therapeutic (e.g., pharmaceutical and medical) and non-therapeutic (e.g., nicotine and cannabinoid) substances. With such substances, it is desirable to include flavor compositions, which are often oil-based, and challenges exist to generate desirable inhalable droplets from the droplet delivery device because the liquid composition may have varying levels of water and oil that affect the interaction and droplet formation through the mesh of the ejector mechanism. [Means for solving the problem]
[0007] In embodiments, the invention includes an ejector mesh and, in some embodiments, other fluid contacting parts of the ejector that have been treated to enhance droplet generation and produce smaller droplet size aerosols that are inhaled into the nose or mouth. In one embodiment, the ejector parts may be treated with an oleophobic coating that reduces adhesion between the oil-containing composition and the ejector fluid contacting parts and the ejector mesh.
[0008]
[0007] In further embodiments, the ejector mesh, and in some cases other ejector parts that come into contact with the fluid composition, may be intentionally roughened prior to application of the oleophobic coating to further reduce adhesion between the additive solution and the ejector mesh and parts and maintain a larger surface contact angle for desired droplet formation from the solution / formulation.
[0009]
[0008] In further embodiments, various coatings and combinations of coatings, including hydrophobic coatings (which repel water), oleophobic coatings (which repel oil or non-polar liquids), and / or grease-repellent coatings (which repel lipids or other non-polar solvents), can be applied to other ejector parts that come into contact with the fluid composition after roughening of the ejector mesh, and optionally to other ejector parts that come into contact with the fluid composition.
[0010] In some embodiments, different ejector materials and different coatings may be utilized in various combinations to facilitate better ejection of droplets from the aerosolized substance.
[0011] In one embodiment of the present invention, the polymer ejector mesh having holes formed by laser ablation may include a metal surface, such as palladium and gold, sputtered onto the polymer mesh material. The metal sputtering adds stiffness to the polymer ejector plate, which has the unexpected effect of increasing droplet ejection from the droplet ejector device.
[0012] In further embodiments of the invention, laser ablation and / or nanomolding of various polymeric materials can be used to create the ejector substrate, such as a mesh or perforated plate. In certain embodiments, polysulfone, polyimide, FEP coated polyimide, FEP, PEEK, PTFE, PVDF and PFA provide advantageous materials for such laser ablation or nanomolding of the ejector parts. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] In one embodiment of the present invention, a droplet delivery device having a powered transducer includes an ejector mechanism having a mesh or similar substrate with holes of a predetermined size and shape. A reservoir of the device supplies a liquid composition to the ejector mechanism for generating droplets having a desired size for inhalation.
[0014] In one embodiment, the liquid composition delivered to the ejector mechanism and mesh is a nicotine formulation containing 0-20% propylene glycol (PG), vegetable glycerin (VG) and glycerol (a purer form of VG). These oils, typically for providing flavor, result in a smaller contact angle than through a mesh having a hydrophobic coating, as described in the incorporated disclosures identified in the related disclosures. For example, testing has shown a reduction in contact angle from 111.3° to 102.8° with a 10% VG solution. This means that as the amount of the above additives increases, the contact angle should decrease. Additionally, the contact angle should decrease depending on which additive is used, i.e., PG >>> glycerol > VG.
[0015]
[0014] To help minimize the adhesion between the additive solution and the ejector material (fluid contact parts) and the ejector mesh, an oleophobic and / or hydrophobic coating, or a combination of coatings, is preferably used, so that droplets are generated that are desirable for inhalation. In particular, in one embodiment, an oleophobic coating is used, and the aqueous solution, and the aqueous solution containing the small hydrocarbon segment additive, can have a contact angle of more than 110°. In one embodiment, a hydrophobic / oleophobic monolayer can be used. Good candidates for achieving this larger contact angle in embodiments of the present invention include using fluorocarbons or organofluorine compounds. Some examples of these perfluorinated compounds can include poly- and perfluoroalkyl substances (PFAS).
[0016]
[0015] In some embodiments, a "general purpose" type oleophobic coating may be used to coat the ejector mesh and ejector parts that come into contact with the oil-based composition. For example, a coating comprising a mixture of 1H,1H,2H,2H-perfluorohexyltrichlorosilane (PFTS) and n-butyl cyanoacrylate (n-BCA) combined in a dichloropentafluoropropane solution may be used in embodiments of the present invention, as described in https: / / cen.acs.org / materials / coatings / Fluorinated-coating-utterly-repellent / 96 / i42 (hereby incorporated by reference). Other coatings in other embodiments may also comprise trichlorosilane head groups on fluorinated hydrocarbons.
[0017] In some embodiments of the present invention, the intentional roughening of the surface of the ejector mesh, and in other embodiments, possibly other ejector parts that come into contact with the oil-containing formulation, provides better adhesion of the oleophobic coating to the desired surface. For example, it is expected that an oleophobic coated surface without roughening has a contact angle of approximately 104°, while roughening the surface and then coating the surface (i.e., a better adhered coating) can provide a contact angle of 115°.
[0018] In various embodiments, roughening the desired surface (e.g., the ejector mesh and / or other ejector parts) may include roughening palladium nickel with oxygen plasma etching, argon sputter etching, ion bombardment, abrasive / roughened beads (e.g., aluminum oxide and zirconium oxide), other chemical etching techniques, etc. The roughened surface is then coated with an oleophobic (and preferably hydrophobic) coating to generate the desired droplets from the liquid formulation of the droplet delivery device.
[0019]
[0018] In other embodiments, various coatings and combinations of coatings, including hydrophobic coatings (which repel water), oleophobic coatings (which repel oil or non-polar liquids), and / or grease-repellent coatings (which repel lipids and other non-polar solvents), can be applied after roughening of the ejector mesh, and optionally to other ejector parts that come into contact with the fluid composition.
[0020]
[0019] In embodiments in which one or more coatings are applied to the roughened surface of an ejector mesh or part, it is preferable to apply the coatings in a sufficient thickness to completely cover the surface peaks and valleys created by the roughening, so that the one or more coatings will adhere to the peaks and valleys created by the roughening, resulting in a coated surface that is ultimately smooth.
[0021] In certain embodiments, a combination of all three of hydrophobic, oleophobic and grease-repellent coatings, particularly those using fluorocarbons and / or halogenated silanes, may be applied to the roughened ejector mesh and / or ejector surfaces that contact the fluid composition of the droplet delivery device. In other words, a coating that is oleophobic / oil-repellent in addition to being hydrophobic may be applied after the desired ejector surface, e.g., ejector mesh / plate, has been roughened. In some embodiments, the aforementioned coatings or combined coatings may not repel liquids, but provide an absence / lack of attraction / adhesion between the ejector surface and the liquid composition.
[0022] In further embodiments where the ejector mesh or similar substrate having holes includes one or more coatings, the coating(s) are also applied, in particular to the inside of the holes or appearance. Different coatings may be applied to different surfaces of the ejector mesh or part, for example, one face or surface may include a first coating type and an opposing face or surface may include a second coating type. In some embodiments, a third coating type may be further applied to the holes or appearance of the ejector mesh or part.
[0023]
[0022] In certain embodiments, one or more coatings may be applied to the ejector mesh or parts to reduce the shear zone and increase slippage of droplets generated by the ejector mechanism. Depending on the type of fluid generating the droplets, the use of different coatings or combinations of coatings on the ejector mesh, ejector substrate holes and / or parts provides better control over the shear zone and maintains a droplet size that is not too large or too small for the intended application of a particular type of droplet.
[0024] In some embodiments, polymeric ejection plates enhance droplet ejection results when metals such as palladium or gold are deposited on the surface of the ejection plate or part by using sputtering, evaporation, or any other form of deposition. Coatings, such as hydrophobic and oleophobic coatings, and combinations thereof, can also be optionally added onto the polymeric ejection plate after the metal is deposited to provide the desired contact angle and further improved droplet ejection. Roughening of the deposited metal surface may also be performed in certain embodiments, and may be optionally utilized in combination with one or more additional coatings (e.g., oleophobic and / or hydrophobic coatings). Metal surfaces deposited on polymer meshes may provide better adhesion of surface coatings in various embodiments of the invention. Metals deposited on the surface of the polymer mesh have a higher Young's modulus than the underlying polymeric material, and thus the metal layer sputtered / deposited on the polymeric material makes the perforated plate more rigid. In embodiments of the invention, a perforated plate, i.e., ejector mesh / ejector plate, has holes (on the order of microns) formed by laser ablation, and a metal layer (on the order of nanometers) sputtered onto the polymer ejector plate provides a metal surface layer that does not impede the passage of liquid that forms droplets on the holes and ejector plate. In some embodiments, the surface of the polymer ejection plate may be roughened and a metal layer may be deposited on the roughened surface.
[0025] In some embodiments, the polymer mesh having holes formed by laser ablation may comprise a polymeric material such as polymethylmethacrylate, polyetherketone, polyetherimide, polyvinylidene fluoride, ultra-high molecular weight polyethylene, polytetrafluoroethylene (PTFE), and the like. In some embodiments, the layer of metal sputtered or deposited on the polymer mesh may comprise a thin layer (e.g., about 30 to about 150 nm, about 60 nm to about 100 nm, about 30 nm, about 60 nm, about 80 nm, about 100 nm, etc., dense sputtering) of precious metals and precious metal alloys such as gold (Au), palladium (Pd), platinum (Pt), silver (Ag), and the like. Palladium has been found to be the preferred deposited / sputtered layer on the polymer in embodiments of the invention. By way of example, holes in a perforated plate (e.g., formed by laser ablation) can be in the range of 1 micron to 6 microns, 2 microns to 5 microns, 3 microns to 5 microns, 3 microns to 4 microns, and similar desirable size ranges of several microns.
[0026] In further embodiments of the invention, laser ablation and / or nanomolding of various polymeric materials can be used to fabricate ejector substrates, such as meshes or perforated plates. In certain embodiments, polysulfone, polyimide, polyimide coated with fluorinated ethylene propylene (FEP), fluorinated ethylene propylene (FEP), polyether ether ketone (PEEK), polytetrafluoroethylene (PTFE), polyvinylidene fluoride or polyvinylidene difluoride (PVDF), and perfluoroalkoxyalkane (PFA) provide advantageous materials for such laser ablation or nanomolding of ejector parts.
[0027] In one aspect of the invention, a droplet delivery device includes an ejector including a polymer mesh having holes and a metal layer deposited on the polymer mesh. In one embodiment, the metal layer is sputtered onto the polymer mesh, although other deposition methods for depositing a metal layer on a mesh of the invention are encompassed.
[0028] In a further aspect, the holes in the droplet delivery device are formed by laser ablation.
[0029] In a further aspect, the metal layer deposited on the ejector mesh of the present invention comprises one or more of gold, palladium, platinum and silver.
[0030] In a further aspect, the metal layer deposited on the ejector mesh of the present invention comprises one or more precious metal alloys.
[0031]
[0030] In a further aspect, the ejector mesh of the present invention comprises one or more of polymethylmethacrylate, polyetheretherketone, polyetherimide, polyvinylidene fluoride, ultra-high molecular weight polyethylene, polysulfone, polyimide, fluorinated ethylene propylene, perfluoroalkoxyalkane, and polytetrafluoroethylene.
[0032] In one aspect of the invention, the polymer mesh is nanomolded.
[0033] In another embodiment of the invention, an oleophobic or hydrophobic coating is applied over the metal layer. In another embodiment of the invention, the metal layer may be roughened to allow better adhesion of the coating, e.g., an oleophobic or hydrophobic coating.
[0034]
[0033] In one particular aspect of the invention, the metal layer of the ejector mesh is roughened to include peaks and valleys, and one or more coatings cover the peaks and valleys of the metal layer to provide a smooth surface.
[0035] In various aspects of the present invention, at least one coating is applied within the pores of an ejector mesh, such as a polymer mesh.
[0036] In another aspect of the invention, a droplet delivery device including an ejector includes a substrate having a hole, a transducer configured to vibrate the substrate, e.g., a powered piezoelectric transducer, a liquid supply to the substrate, and one or more coatings applied to a roughened surface of the substrate having a hole. In one aspect, the substrate is a polymer. In one aspect, the one or more coatings of the substrate include an oleophobic coating. In another aspect, the one or more coatings of the substrate include a deposited metal. In another aspect, the one or more coatings of the substrate include a hydrophobic coating.
[0037]
[0036] Although the present invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made without departing from the scope of the invention and that equivalents may be substituted for the elements of the invention. In addition, many modifications may be made to adapt a particular situation or material to the present teachings without departing from the essential scope of the invention. Therefore, it is not intended that the invention be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but rather that the invention will include all embodiments falling within the scope of the appended claims.
Claims
1. A polymer mesh having pores, A metal layer deposited on a polymer mesh, A droplet delivery device comprising an ejector, which includes a liquid feeder that fluidly communicates with the polymer mesh, and which contains a liquid containing nicotine in combination with propylene glycol, vegetable glycerin and / or glycerol.
2. The droplet delivery device according to claim 1, wherein holes are formed by laser ablation.
3. The droplet delivery device according to claim 1, wherein a metal layer is sputtered onto a polymer mesh.
4. The droplet delivery device according to any one of claims 1 to 3, wherein the metal layer comprises at least one metal selected from the group consisting of gold, palladium, platinum, and silver.
5. A droplet delivery device according to any one of claims 1 to 3, wherein the metal layer comprises one or more types of precious metal alloys.
6. A droplet delivery device according to any one of claims 1 to 3, wherein the polymer mesh comprises one or more of polymethyl methacrylate, polyether ether ketone, polyetherimide, polyvinylidene fluoride, ultra-high molecular weight polyethylene, polysulfone, polyimide, fluorinated ethylene propylene, perfluoroalkoxyalkane, and polytetrafluoroethylene.
7. A droplet delivery device according to any one of claims 1 to 3, wherein the polymer mesh is nanomolded.
8. A droplet delivery device according to any one of claims 1 to 3, further comprising an oil-repellent or hydrophobic coating on a metal layer.
9. A droplet delivery device according to any one of claims 1 to 3, further comprising a hydrophobic coating on a metal layer.
10. A droplet delivery device according to any one of claims 1 to 3, wherein the metal layer is roughened.
11. A droplet delivery device according to any one of claims 1 to 3, wherein the metal layer is roughened to include ridges and valleys, and one or more coatings cover the ridges and valleys of the metal layer to provide a smooth surface.
12. A droplet delivery device according to any one of claims 1 to 3, further comprising at least one coating applied to a plurality of pores of a polymer mesh.
13. A substrate having holes, A transducer configured to vibrate a substrate, Liquid feeder to a substrate, including a liquid containing nicotine in combination with propylene glycol, vegetable glycerin and / or glycerol, and One or more coatings applied to the roughened surface of a substrate A droplet delivery device including an ejector.
14. The droplet delivery device according to claim 13, wherein the substrate is a polymer and includes a metal on which one or more coatings are deposited.
15. The droplet delivery device according to claim 13 or 14, wherein one or more coatings include a hydrophobic coating.