Superhydrophobic coatings

Patent metadata

Field	Value
Publication number	US-2025382476-A1
Application number	US-202318875157-A
Country	US
Kind code	A1
Filing date	Jun 14, 2023
Priority date	Jun 14, 2022
Publication date	Dec 18, 2025
Grant date	—

Abstract

A composition comprising an emulsion comprising a plurality of particles is provided. An article comprising a substrate, and a plurality of particles comprising a void core and a shell, wherein the plurality of particles are in the form of a coating layer on the substrate is provided. Further, a method for coating a substrate is provided.

First claim

1 . A composition, comprising a plurality of core-shell particles dispersed within a hydrophobic solvent, wherein:
a. the core of said core-shell particles comprises an aqueous solution; b. the shell of said core-shell particles comprises hydrophobic metal oxide nanoparticles; and wherein the shell is in contact with polymeric particles; c. a w/w ratio of said hydrophobic solvent to said aqueous solution within said composition is between 1:1 and 10:1; and d. a w/w concertation of the hydrophobic metal oxide nanoparticles within said composition is between 0.5 and 5%; e. an average cross-section of the core-shell particles is between 1 μm and 100 μm; and f. the hydrophobic solvent is or comprises dimethyl carbonate (DMC).

2 . The composition of claim 1 , wherein a w/w concertation of the hydrophobic metal oxide nanoparticles within said composition is between 1.5 and 3%.

3 . The composition of claim 1 , wherein a ratio between the hydrophobic metal oxide nanoparticles and the polymeric particles is between 30:1 and 1:1.

4 . The composition of claim 1 , wherein a w/w concertation of the polymeric particles within the composition is between 0.05 and 2%; and wherein the polymeric particles are latex nanoparticles comprising a thermoplastic polymer characterized by a glass transition temperature between 1° and 90° C.

5 . The composition claim 1 , wherein an average cross-section of said polymeric particles is between 1 nm and 100 nm.

6 . The composition claim 1 , wherein said hydrophobic metal oxide nanoparticles comprise a chemical modification covalently attached to a metal oxide particle, the metal oxide particle is or comprises SiO 2 particle.

7 . The composition of claim 6 , wherein said chemical modification comprises any of a polysiloxane, a polysilane, (C1-C20)alkylsilyl group, a (C1-C20)alkoxysilane group including any copolymer or any combination thereof.

8 . The composition of claim 7 , wherein said polysiloxane is PDMS.

9 . (canceled)

10 . The composition of claim 4 , wherein the thermoplastic polymer comprises a polyacrylate, a polyester, a polyurethane, polystyrene including any combination, or any copolymer thereof.

11 . The composition claim 1 , further comprising between 0.1 and 20% by weight of biologically active agent; and wherein said biologically active agent is selected from: an anti-microbial agent comprising an essential oil, a wax or both; a preservative; and a pesticide, or any combination thereof.

12 . (canceled)

13 . A coated substrate, comprising at least one surface of a substrate in contact with a coating, wherein:
a. the coating comprises a plurality of hollow microparticles; b. a shell of the hollow microparticles comprises hydrophobic metal oxide nanoparticles and a thermoplastic polymer; and c. a ratio between the hydrophobic metal oxide nanoparticles and the thermoplastic polymer within the shell is between 30:1 and 1:1.

14 . The coated substrate of claim 13 , wherein said thermoplastic polymer is in a form of latex particles; wherein the hydrophobic metal oxide nanoparticles are in contact with the latex particles, and wherein a weight ratio between the hydrophobic metal oxide nanoparticles and the latex particles within the coating is between 25:1 and 5:1; and wherein the coating is a water repellent coating; optionally wherein the coating is by any one of: anti-biofilm coating, anti-microbial coating, or both.

15 . The coated substrate of claim 13 , wherein the thermoplastic polymer comprises a polyacrylate, a polyester, a polyurethane, polystyrene including any combination, or any copolymer thereof; and wherein said hydrophobic metal oxide nanoparticles comprise chemically modified SiO 2 particles.

16 . The coated substrate of claim 13 , wherein the coated substrate is characterized by any one of: a roll-off angle between 0 and 10°; and a water contact angle of at least 120°; and wherein the substrate comprises a plastic substrate, a cellulose-based substrate, a glass substrate, a ceramic substrate, a metal substrate, a textile substrate, and a wood substrate or any combination thereof.

17 . (canceled)

18 . (canceled)

19 . The coated substrate of claim 15 , wherein said chemically modified SiO 2 particles are PDMS modified silica particles.

20 . The coated substrate of claim 13 , wherein the coating is in a form of a continuous layer, characterized by a thickness of between 0.5 and 50 um.

21 . The coated substrate of claim 13 , wherein an outer surface of the coated substrate is characterized by a route mean square of surface height (RMS) of between 20 and 100 nm.

22 . (canceled)

23 . The coated substrate of claim 14 , wherein the latex particles are acrylate latex particles and are characterized by an average particle size between 1 and 100 nm; wherein the substrate is the cellulose-based substrate, and wherein the coated substrate is characterized by water absorption of at most 30% by weight of the substrate.

24 . (canceled)

25 . (canceled)

26 . (canceled)

27 . The coated substrate of claim 13 , fabricated by applying the composition of claim 1 on top of the substrate; and exposing the substrate in contact with the composition under conditions suitable for drying, thereby obtaining the coated substrate.

28 . The coated substrate of claim 27 , wherein the conditions suitable for drying comprise a temperature between 1° and 200° C.

Assignees

• The State Of Israel Ministry Of Agriculture & Rural Development Agricultural Res
• Univ Bar Ilan

Inventors

• Mechrez Guy
• Mani Karthik Ananth
• Cohen Raz
• Pirmatova Madina
• Bareket Yifat
• Banin Ehud

Classifications

• C09D5/14

  Paints containing biocides, e.g. fungicides, insecticides or pesticides (C09D5/16 takes precedence) · CPC title

• B05D2601/20

  used for non-pigmentation effect · CPC title

• B05D3/0254

  After-treatment · CPC title

• C09D7/62 Primary

  modified by treatment with other compounds · CPC title

• C09D7/67

  Particle size smaller than 100 nm · CPC title