Liquid-Impregnated Surfaces, Methods of Making, and Devices Incorporating the Same

Abstract

The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority to and the benefit of, and incorporates herein by reference in its entirety, U.S. Provisional Patent Application No. 61 / 515,395, which was filed on Aug. 5, 2011.TECHNICAL FIELD [0002]This invention relates generally to non-wetting and low adhesion surfaces. More particularly, in certain embodiments, the invention relates to non-wetting surfaces that resist liquid impalement, ice formation, scale formation, hydrate formation, and / or have antifouling properties.BACKGROUND [0003]The advent of micro / nano-engineered surfaces in the last decade has opened up new techniques for enhancing a wide variety of physical phenomena in thermofluids sciences. For example, the use of micro / nano surface textures has provided nonwetting surfaces capable of achieving less viscous drag, reduced adhesion to ice and other materials, self-cleaning, and water repellency. These improvements result generally from diminished contact (i...

AI Technical Summary

Benefits of technology

This patent describes a new type of non-wetting surface that has a liquid inside it, either by being impregnated with a gas or by having tiny wells filled with liquid. These surfaces are much more durable and resistant to damage than previous non-wetting surfaces that only had gas inside them. The methods described can be used in various applications to reduce viscous drag, prevent ice formation, and minimize the accumulation of impinging liquids. The liquid-impregnated surfaces have much higher resistance to impalement, making them better suited for high-pressure applications. The use of micro-scale features is preferred over nano-scale features as they are easier and less expensive to fabricate. The liquid-impregnated surfaces can be customized for different applications, such as reducing water drag on surfaces, preventing fogging, inhibiting ice formation, reducing drag in oil and gas pipelines, and preventing corrosion. The surfaces can also be used as anti-fouling surfaces to resist adsorption of debris.

Problems solved by technology

One of the drawbacks of existing non-wetting surfaces (e.g., superhydrophobic, superoleophobic, and supermetallophobic surfaces) is that they are susceptible to impalement, which destroys the non-wetting capabilities of the surface.

Another drawback with existing non-wetting surfaces is that they are susceptible to ice formation and adhesion.

Removal of the ice can be difficult because the ice may interlock with the textures of the surface.

Similarly, when these surfaces are exposed to solutions saturated with salts, for example as in desalination or oil and gas applications, scale builds on surfaces and results in loss of functionality.

Similar limitations of existing non-wetting surfaces include problems with hydrate formation, and formation of other organic or inorganic deposits on the surfaces.

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