Creating Superhydrophobic Surfaces

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[SIZE=4]This is an article I just posted on my blog. Just wanted to make it available here. Also. As I continue to work with this technology if anyone would like me to send them any info directly just send me a request by email to [email protected]
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[COLOR=#0000cd]OK. Many years have passed since Repcon. Most of you out there have never even heard of this product. It was first created for jet aircraft. Then came RainX. Next The Invisible Shield. These three at that time were owned by the same company. Over in the UK at about the same time from a completely different company came Clear Shield. Now over thirty years has passed since this time. However the chemistry used for these products is still known and in use.

Many other products and systems have been developed in later years. Based on somewhat different chemistries such as cross linking siloxanes, organofluorochlorosilanes, and silane functionalized silica nanoparticles. As it turns out hydrophobic glass surfaces are not too difficult to create. However superhydrophobic surfaces are somewhat more challenging. It has been learned from studying the nanoscopic surface of the lotus leaf that more is involved than just chemistry. The physical surface must have a certain ‘structure’. When the right chemistry is coupled with this then contact angles greater than 150 degrees can be attained. Superhydrophobicity can be tested also by whether water drops will roll down a clean surface at only a 10 degree angle.

The benefits of such ‘new’ surfaces are many. First they will resist hard water spots, paint, wood stains, grease, and other chemistries. They also improve vision during rain storms. Especially if applied to vehicular vision glass. The right treatments will resist scratches making glass and mirror mar resistant. Likewise superhydrophobic window cleaning is a breeze. It completely eliminates the need for squeegees and hence the skill factor. Microfiber applicators can be used inside. And a simple garden hose will do the outside. Throw away your store bought cleaners that just coat windows with soap creating filmy glass. Pure water is all you’ll need.

If you want to buy into this technology you will need a window cleaning company that is Glass Smart. One word of caution however. The creators of superhydrophobic systems and products claim that superhydrophobic glass is ‘self cleaning’. This is not completely true. Windows will still get dirty and spotted. Thus they will still need to be cleaned. Which can be done with microfiber applicator/wipes or the garden hose if your water isn’t hard. But they will still need to be cleaned. It is also true that under certain conditions inside surfaces can become filmy quicker than if there were no coating applied at all. In fact if that surface were ‘structured’ correctly without any coating used at all it will appear to stay cleaner longer. This can be proven over a span of just a month or two by a simple experiment on your window. Now these are the kind of things a company that sells superhydrophobic glass treatments will absolutely NOT tell you. But a Glass Smart window cleaning company will. It pays to listen to the independant contractor/consultant.[/COLOR]

[COLOR=#0000cd][SIZE=4]www.glass-smart.blogspot.com

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I have heard about “self cleaning windows” before from customers and it always confused me. How can a window stay clean on its own without the occassional help from a window cleaner? This makes a lot more sense now that you are talking about them being superhydrophobic. Thanks for the article.

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Hi Jason,

The term ‘Self Cleaning’ refers to a hydrophylic surface that sheets not beads water. It is water loving not water hating. And is photocatalytic so it is energized by the sun to break up dirt into smaller particles. Then when it rains this dirt is sheeted away. In theory. I have cleaned self cleaning windows before. I would rather apply a hydrophobic coating that offers so many more advantages.

Henry

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I think they are calling them low maintenance windows these days. Still don’t cut the mustard for bird dung, but on the whole the titanium dioxide does the job, although not a complete job & will still need cleaning.

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Hi Karl,

Precisely correct. Thanx for the insertion about bird crap. I used to do a Burger King up in Lebanon NH that had about forty horizontal sloping plates. Every week they were loaded with bird crap. No ‘self cleaning’ titanium dioxide window would have stood a chance! Maybe some strategically placed anti-bird wire. Also. I have always wondered what window manufacturers would suggest we use to remove silicone caulk, wood stain, paint, deck sealer, concrete, or some other creative deposit from these high tech but sensitive surfaces.

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Hi Henry,
I guess that I was confused by the hydrophyllic windows being called self cleaning and not the hydrophobic ones. I feel the same way about having hydrophobic windows and them making things easier. I will say that hydrophyllic definitely make WFP work seem easier so in a way that makes sense as far as “self cleaning” windows go. I would just naturally think that the smoother surface that you have the cleaner that it is going to stay.

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Henry, I have a commercial account that I have been doing for years with a wfp. The first time I cleaned the windows exterior was right after they had the building waterproofed and painted. They construction cleaned the windows and did a good job. The windows seem to be [B]hydrophobic because of the residue from the waterproof chemical. Have you ever seen this before? The windows come out great every time I clean them with a wfp pole.[/B]