Hydrophobic coating including oxide of Ni and/or Cr

Stock material or miscellaneous articles – Composite – Of quartz or glass

Reexamination Certificate

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Details

C428S433000, C428S697000, C428S699000, C428S701000, C428S702000, C427S162000, C427S166000, C427S419200

Reexamination Certificate

active

06689476

ABSTRACT:

This invention relates to a hydrophobic coating to be used in the context of coated articles. More particularly, this invention relates to a hydrophobic coating comprising a layer having a contact angle(s) &thgr; which does not significantly decrease upon exposure to ultraviolet (UV) radiation. In certain example embodiments, the layer may be of or include NiCrO
x
, or any other suitable material.
BACKGROUND OF THE INVENTION
Hydrophobic coatings are known in the art, and are typically characterized by high contact angles &thgr;. Contact angles, in general, are discussed for example in U.S. Ser. Nos. 09/442,805 filed Nov. 18, 1999 (now U.S. Pat. No. 6,338,901), and 09/583,862 filed Jun. 1, 2000 (now U.S. Pat. No. 6,335,086), both of which are hereby incorporated herein by reference. Contact angle &thgr; is explained in the context of
FIGS. 1 and 2
.
The initial contact angle &thgr; of a conventional glass substrate
1
with sessile water drop
3
thereon is typically from about 22-24 degrees, although it may dip as low as 17 or so degrees in some circumstances, as illustrated in FIG.
1
. Thus, conventional glass substrates are not particularly hydrophobic in nature. The provision of a hydrophobic coating or layer system
5
on substrate
1
causes the contact angle &thgr; to increase to the angles discussed herein, as shown in FIG.
2
. As shown in
FIG. 2
, hydrophobic coatings can have initial contact angles &thgr; of above 90 degrees for water repelling purposes. An “initial” contact angle &thgr; means prior to exposure to environmental conditions such as sun, rain, abrasions, ultraviolet radiation, humidity, etc.
For example, U.S. Pat. No. 5,378,527 discloses a diamond-like carbon (DLC) coating having a contact angle of 90 degrees in certain examples, and 120 degrees in other examples. Unfortunately, it has been found that initial contact angles &thgr; of DLC coatings drop dramatically upon prolonged exposure to ultraviolet (UV) radiation in an ambient atmosphere including sun, rain and the like. This UV stability problem can in some instances result in contact angle &thgr; dropping from an initial value of 80 degrees or higher to a post-UV value of less than 20 degrees.
In view of the above, those skilled in the art will appreciate that there exists a need in the art for a UV stable hydrophobic coating which does not experience a significant loss/decrease in contact angle &thgr; value upon prolonged exposure (e.g., 100-250 hours) to UV radiation. Other needs will also become apparent to those skilled in the art upon review of the instant document.
BRIEF SUMMARY OF THE INVENTION
An object of this invention is to provide a hydrophobic coating that has a rather high contact angle &thgr; of at least about 70 degrees, both before and after exposure to ultraviolet (UV) radiation (e.g., about 100-250 hours of UV exposure). In other words, an object of this invention is to provide a hydrophobic coating that is UV stable (i.e., not subject to significant contact angle &thgr; degradation upon UV exposure).
Another object of this invention is to provide hydrophobic coating that is transmissive of at least 60% of visible light, more preferably at least 70% of visible light, and most preferably at least 75% of visible light.
Another object of this invention is to provide a hydrophobic coating that is durable enough to be used in the context of vehicle windows, architectural windows, and/or the like.
Another object of this invention is to provide a hydrophobic coating including at least one NiCrO
x
inclusive layer.
Another object of this invention is to fulfill one or more of the above listed objects and/or needs.


REFERENCES:
patent: 4603805 (1986-08-01), Rogers
patent: 4953922 (1990-09-01), Granqvist
patent: 5030478 (1991-07-01), Lin et al.
patent: 5229194 (1993-07-01), Lingle et al.
patent: 5264099 (1993-11-01), Szczyrbowski et al.
patent: 5376455 (1994-12-01), Hartig et al.
patent: 5378527 (1995-01-01), Nakanishi et al.
patent: 5436047 (1995-07-01), Howard et al.
patent: 5514476 (1996-05-01), Hartig et al.
patent: 5547768 (1996-08-01), Topolski et al.
patent: 5563734 (1996-10-01), Wolfe et al.
patent: 5798134 (1998-08-01), Sato et al.
patent: 5876854 (1999-03-01), Kawazu et al.
patent: 5909314 (1999-06-01), Oka et al.
patent: 6090489 (2000-07-01), Hayakawa et al.
patent: 6156389 (2000-12-01), Brown et al.
patent: 6235833 (2001-05-01), Akamatsu
patent: 6335086 (2002-01-01), Veerasamy
patent: 6338901 (2002-01-01), Veerasamy
patent: 2 792 003 (2000-10-01), None
patent: 2-258250 (1990-10-01), None
patent: 06-219785 (1994-08-01), None
Translation of JP 02-258250.*
“Surface Science of Metal Oxides”, Victor Heinrich & P.A. Cox, 1994, pp. 14-43.
PCT Search Report dated Nov. 19, 2002.

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