U.S. patent application number 11/665084 was filed with the patent office on 2008-06-19 for coating compositions, articles, and methods of coating articles.
This patent application is currently assigned to SDC Technologies, Inc.. Invention is credited to Ren-Zhi Jin, Andreas Schneider.
Application Number | 20080145547 11/665084 |
Document ID | / |
Family ID | 36203444 |
Filed Date | 2008-06-19 |
United States Patent
Application |
20080145547 |
Kind Code |
A1 |
Schneider; Andreas ; et
al. |
June 19, 2008 |
Coating Compositions, Articles, And Methods Of Coating Articles
Abstract
To provide transparent plastic coatings with a combination of
abrasion resistance and formability, a composition comprises an
aqueous-organic solvent mixture containing hydrolysis products and
partial condensates of an epoxy functional silane and/or a diol
functional organopolysiloxane mixed with a multifunctional
crosslinker selected from multifunctional carboxylic acids, an
hydrides or silylated anhydrides, wherein the molar ratio of the
epoxy functional silane and/or the diol functional
organopolysiloxane to the multifunctional crosslinker is from about
10:1 to 1:10, and water in an amount sufficient to hydrolyze the
components.
Inventors: |
Schneider; Andreas; (Orange,
CA) ; Jin; Ren-Zhi; (Irvine, CA) |
Correspondence
Address: |
CALFEE HALTER & GRISWOLD, LLP
800 SUPERIOR AVENUE, SUITE 1400
CLEVELAND
OH
44114
US
|
Assignee: |
SDC Technologies, Inc.
Anaheim
CA
|
Family ID: |
36203444 |
Appl. No.: |
11/665084 |
Filed: |
October 12, 2005 |
PCT Filed: |
October 12, 2005 |
PCT NO: |
PCT/US2005/036458 |
371 Date: |
June 11, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60618014 |
Oct 12, 2004 |
|
|
|
Current U.S.
Class: |
427/386 ;
427/387; 525/477; 528/32 |
Current CPC
Class: |
Y10T 428/31511 20150401;
C08J 7/043 20200101; C08G 59/4085 20130101; C08G 59/423 20130101;
C09D 183/06 20130101; C09D 175/04 20130101; C09D 183/04 20130101;
C08G 77/16 20130101; C08J 7/054 20200101; Y10T 428/31663 20150401;
C08J 2483/00 20130101; C08G 18/289 20130101; C08J 7/0427 20200101;
C08G 18/8061 20130101; C08J 7/046 20200101; C09D 183/06 20130101;
C08L 2666/44 20130101 |
Class at
Publication: |
427/386 ;
427/387; 528/32; 525/477 |
International
Class: |
C08G 77/16 20060101
C08G077/16; B05D 5/00 20060101 B05D005/00; C08G 77/38 20060101
C08G077/38; B05D 3/02 20060101 B05D003/02 |
Claims
1. A composition which, when applied to a substrate and cured,
provides an abrasion resistant formable coating on said substrate,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of at least one of an epoxy
functional silane and a diol functional organopolysiloxane and at
least one multifunctional crosslinker, wherein said multifunctional
crosslinker comprises a silylated multifunctional anhydride, and
wherein said at least one of said epoxy functional silane and said
diol functional organopolysiloxane is present in a molar ratio to
said multifunctional crosslinker from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze said epoxy functional
silane, said diol functional organopolysiloxane, and said silylated
multifunctional crosslinker.
2. The composition as claimed in claim 1 wherein said at least one
of said epoxy functional silane and said diol functional
organopolysiloxane is present in a molar ratio to said
multifunctional crosslinker of about 2:1 to 1:2.
3. The composition as claimed in claim 1 wherein said coating can
be formed to a radius from about 1 inch to less than about 10
inches on a polycarbonate substrate.
4. The composition as claimed in claim 1 wherein said coating can
be formed to a radius from about 3 inches to about 5 inches on a
polycarbonate substrate.
5. The composition as claimed in claim 1 wherein said coating has a
Taber number of between less than about 10 percent to less than
about 2 percent after 50 revolutions of a Taber wheel.
6. The composition as claimed in claim 1 wherein said coating has a
Taber number of between less than about 45 percent to less than
about 15 percent after 200 revolutions of a Taber wheel.
7. The composition as claimed in claim 1 wherein said at least one
of said epoxy functional silane and said diol functional
organopolysiloxane comprises about 5 to about 90 percent by weight
of the solids of said composition, and wherein said multifunctional
crosslinker comprises about 10 to about 95 percent by weight of the
solids of said composition.
8. The composition as claimed in claim 1 wherein the solvent
constituent of said aqueous-organic solvent mixture comprises from
about 40 to about 98 percent by weight of the composition.
9. The composition as claimed in claim 1 wherein the solvent
constituent of said aqueous-organic solvent mixture is selected
from an ether, a glycol or a glycol ether, a ketone, an ester, a
glycolether acetate, alcohols having the formula ROH where R is an
alkyl group containing from 1 to about 10 carbon atoms, and
mixtures thereof.
10. The composition as claimed in claim 1 wherein the solvent
constituent of said aqueous-organic solvent mixture is selected
from glycols, ethers, glycol ethers having the formula
R.sup.1--(OR.sup.2).sub.x--OR.sup.1 where x is 0, 1, 2, 3 or 4,
R.sup.1 is hydrogen or an alkyl group containing from 1 to about 10
carbon atoms and R.sup.2 is an allylene group containing from 1 to
about 10 carbon atoms and combinations thereof.
11. The composition as claimed in claim 1 wherein said epoxy
functional silane is represented by the formula
R.sup.3.sub.xSi(OR.sup.4).sub.4-x, wherein: x is an integer of 1, 2
or 3; R.sup.3 is H, an allyl group, a functionalized allyl group,
an alkylene group, an aryl group, an allyl ether, and combinations
thereof containing from 1 to about 10 carbon atoms and having at
least 1 epoxy functional group; R.sup.4 is H, an alkyl group
containing from 1 to about 5 carbon atoms, an acetyl group, a
--Si(OR.sup.5).sub.3-yR.sup.6.sub.y group where y is an integer of
0, 1, 2, or 3, and combinations thereof; R.sup.5 is H, an allyl
group containing from 1 to about 5 carbon atoms, an acetyl group,
or another --Si(OR.sup.5).sub.3-yR.sup.6.sub.y group and
combinations thereof; and R.sup.6 is H, an alkyl group, a
functionalized alkyl group, an alkylene group, an aryl group, an
alkyl ether, and combinations thereof containing from 1 to about 10
carbon atoms.
12. A composition which, when applied to a substrate and cured,
provides an abrasion resistant formable coating on said substrate,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein said multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein said diol
functional organopolysiloxane is present in a molar ratio to said
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze said diol functional
organopolysiloxane and said silylated multifunctional
crosslinker.
13. The composition as claimed in claim 12 wherein said
aqueous-organic solvent mixture further comprises hydrolysis
products and partial condensates of an epoxy functional silane and
said at least one multifunctional crosslinker.
14. A composition which, when applied to a substrate and cured,
provides an abrasion resistant formable coating on said substrate,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane and
at least one multifunctional crosslinker, wherein said
multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein said at least one of said
epoxy functional silane is present in a molar ratio to said
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional silane
and the multifunctional crosslinker, wherein said composition
contains an amount of at least one of tetrafunctional silanes,
disilanes, and alkyl silanes insufficient to render said coating
rigid on said substrate.
15. The composition as claimed in claim 14 wherein said composition
includes at least one of a tetrafunctional silane and a disilane,
and wherein said epoxy functional silane is present in a molar
ratio to said at least one of said tetrafunctional silane and said
disilane of at least about 5.5:1.
16. The composition as claimed in claim 14 wherein said
aqueous-organic solvent mixture further comprises hydrolysis
products and partial condensates of a diol functional
organopolysiloxane and said multifunctional crosslinker.
17. The composition as claimed in claim 14 wherein: said
tetrafunctional silane has a formula of Si(OR.sup.9).sub.4, where
R.sup.9 is H, an alkyl group containing from 1 to about 5 carbon
atoms and ethers thereof, an (OR.sup.9) carboxylate, a
--Si(OR.sup.10).sub.3 group where R.sup.10 is a H, an alkyl group
containing from 1 to about 5 carbon atoms and ethers thereof, an
(OR.sup.10) carboxylate, or another --Si(OR.sup.10).sub.3 group and
combinations thereof, wherein: said disilane has a formula of
(R.sup.11O).sub.xR.sup.12.sub.3-xSi--R.sup.13.sub.ySiR.sup.14.sub.3-x(OR.-
sup.15).sub.x; wherein x is 0, 1, 2, or 3 and y is 0 or 1; wherein
R.sup.12 and R.sup.14 comprises H, an allyl group containing from
about 1 to about 10 carbon atoms, a fictionalized alkyl group, an
alkylene group, an aryl group, an alkypolyether group, and
combinations thereof; wherein R.sup.12 and R.sup.15 comprises H, an
allyl group containing from about 1 to, about 10 carbon atoms, an
acetyl group, and combinations thereof; wherein if y is 1 then
R.sup.13 comprises an alkylene group containing from about 1 to
about 12 carbon atoms, an alkylenepolyether containing from about 1
to about 12 carbon atoms, an aryl group, an alkylene substituted
aryl group, an alkylene group which may contain one or more
olefins, S, or O; wherein it x is 0 then R.sup.12 and R.sup.14
comprises Cl or Br; and wherein if y is 0 then there is a direct
silicon-silicon bond, and wherein: said allyl silane has a formula
of R.sup.16.sub.xSi(OR.sup.17).sub.4-x where x is a number of 1, 2
or 3; R.sup.16 is H, or an alkyl group containing from 1 to about
10 carbon atoms, a functionalized alkyl group, an allylene group,
an aryl group an alkoxypolyether group and combinations thereof;
R.sup.17 is H, an alkyl group containing from 1 to about 10 carbon
atoms, an acetyl group; and combinations thereof.
18. The composition as claimed in claim 14 wherein said composition
includes at least one alkyl silane, and wherein said epoxy
functional silane is present in a molar ratio to said at least one
allyl silane of at least about 2.5:1.
19. An article, comprising: a substrate and an abrasion resistant
formable coating formed on at least one surface of said substrate
by curing a coating composition, comprising: an aqueous-organic
solvent mixture having hydrolysis products and partial condensates
of at least one of an epoxy functional silane and a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein said multifunctional crosslinker comprises a silylated
multifunctional anhydride, and wherein said at least one of said
epoxy functional silane and said diol functional organopolysiloxane
is present in a molar ratio to said multifunctional crosslinker
from about 10:1 to 1:10; and an amount of water sufficient to
hydrolyze said epoxy functional silane, said diol functional
organopolysiloxane, and said silylated multifunctional
crosslinker.
20. The article as claimed in claim 19 wherein said article
comprises a formed article comprising a formed substrate and said
abrasion resistant formable coating formed on at least one surface
of said substrate by applying said coating composition to a
substrate, curing said coating composition, and subsequently
forming said substrate such that said formed substrate is
formed.
21. The article as claimed in claimed 19 further comprising at
least one primer disposed on said at least one surface of said
substrate between said substrate and said coating.
22. An article, comprising: a substrate and an abrasion resistant
formable coating formed on at least one surface of said substrate
by curing a coating composition, comprising: an aqueous-organic
solvent mixture having hydrolysis products and partial condensates
of a diol functional organopolysiloxane and at least one
multifunctional crosslinker, wherein said multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein said diol functional organopolysiloxane is
present in a molar ratio to said multifunctional crosslinker of
from about 10:1 to 1:10; and an amount of water sufficient to
hydrolyze said diol functional organopolysiloxane and said
silylated multifunctional crosslinker.
23. An article, comprising: a substrate and an abrasion resistant
formable coating formed on at least one surface of said substrate
by curing a coating composition, comprising: an aqueous-organic
solvent mixture having hydrolysis products and partial condensates
of an epoxy functional silane and at least one multifunctional
crosslinker, wherein said multifunctional crosslinker is selected
from multifunctional carboxylic acids, multifunctional anhydrides,
and silylated multifunctional anhydrides, and wherein said epoxy
functional silane is present in a molar ratio to said
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze said epoxy functional
silane and said silylated multifunctional crosslinker, wherein said
composition contains an amount of at least one of tetrafunctional
silanes, disilanes, and alkyl silanes insufficient to render said
coating rigid on said substrate.
24. The article as claimed in claim 23 wherein said coating
composition includes at least one of a tetrafunctional silane and a
disilane, and wherein said epoxy functional silane is present in a
molar ratio to said at least one of said tetrafunctional silane and
said disilane of at least about 5.5:1.
25. The article as claimed in claim 23 wherein said coating
composition includes at least one alkyl silane, wherein said epoxy
functional silane is present in a molar ratio to said at least one
alkyl silane of at least about 2.5:1.
26. A process for providing a substantially transparent abrasion
resistant formable coating, comprising: applying a coating
composition to a substrate; and curing said coating composition,
wherein said coating composition comprises: an aqueous-organic
solvent mixture having hydrolysis products and partial condensates
of at least one of an epoxy functional silane and a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein said multifunctional crosslinker comprises a silylated
multifunctional anhydride, and wherein said at least one of said
epoxy functional silane and said diol functional organopolysiloxane
is present in a molar ratio to said multifunctional crosslinker
from about 10:1 to 1:10; and an amount of water sufficient to
hydrolyze said epoxy functional silane, said diol functional
organopolysiloxane, and said silylated multifunctional
crosslinker.
27. The process as claimed in claim 26 further comprising the step
of forming said coated substrate.
28. The process as claimed in claim 26 further comprising applying
a primer to said substrate prior to applying said coating
composition to said substrate on said primer.
29. A process for providing an abrasion resistant formable coating,
comprising: applying a coating composition to a substrate; and
curing said coating composition, wherein said coating composition
comprises: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein said multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein said diol
functional organopolysiloxane is present in a molar ratio to said
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze said diol functional
organopolysiloxane and said silylated multifunctional
crosslinker.
30. A process for providing an abrasion resistant formable coating,
comprising: applying a coating composition to a substrate; and
curing said coating composition, wherein said coating composition
comprises: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane and
at least one multifunctional crosslinker, wherein said
multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein said epoxy functional
silane is present in a molar ratio to said multifunctional
crosslinker of from about 10:1 to 1:10; and an amount of water
sufficient to hydrolyze said epoxy functional silane and said
silylated multifunctional crosslinker, wherein said composition
contains an amount of at least one of tetrafunctional silanes,
disilanes, and alkyl silanes insufficient to render said coating
rigid on said substrate.
31. The method as claimed in claim 30 wherein said composition
includes at least one of a tetrafunctional silane and a disilane,
and wherein said epoxy functional silane is present vin a molar
ratio to said at least one of said tetrafunctional silane and said
disilane of at least about 5.5:1.
32. The method as claimed in claim 30 wherein said composition
includes at least one alkyl silane, and wherein said epoxy
functional silane is present in a molar ratio to said at least one
alkyl silane of at least about 2.5:1.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and any other benefit of
U.S. Provisional Application Ser. No. 60/618,014, filed Oct. 12,
2004, the entirety of which is incorporated by reference
herein.
FIELD OF THE INVENTION
[0002] The present invention relates to coating compositions,
articles, and methods of coating articles. More particularly, the
present invention relates to stable coating compositions that
provide abrasion resistant formable coatings when cured on a
substrate.
BACKGROUND
[0003] Glass glazing can be substituted with transparent materials,
such as plastics, which do not shatter or are more resistant to
shattering than glass. For example, transparent materials made from
synthetic organic polymers are utilized in public transportation
vehicles such as trains, buses, taxis and airplanes. Lenses for eye
glasses and other optical instruments, as well as glazing for large
buildings, call also employ shatter-resistant, transparent
plastics. Additionally, the lighter weight of these plastics in
comparison to glass can be a further advantage, especially in the
transportation industry where the weight of the vehicle is a major
factor in its fuel economy.
[0004] While transparent plastics provide the major advantage of
being more resistant to shattering, lighter than glass, and having
design flexibility, a serious drawback lies in the ease with which
these plastics mar and scratch due to everyday contact with
abrasives such as dust or cleaning equipment. Marring results in
impaired visibility and poor aesthetics, and often requires
replacement of the glazing or lens or the like.
[0005] To improve the abrasion resistance of plastics,
mar-resistant coatings have been developed. The main disadvantage
of these abrasion resistant compositions is that they may not be
formable after curing. Poor formability means that bending or
working a coated article will often lead to cracking or crazing of
the coating. As a consequence, articles must be coated after
forming, which may entail time delays and shipment of uncoated
articles which may be inadvertently abraded in transit. Thus, there
remains a need in the art for coatings having good abrasion
resistance and formability.
SUMMARY OF THE INVENTION
[0006] In accordance with embodiments of the present invention,
compositions which, when applied to a substrate and cured, provide
an abrasion resistant formable coating on the substrate are
provided. The compositions can comprise an aqueous-organic solvent
mixture having hydrolysis products and partial condensates of at
least one of an epoxy functional silane and a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker comprises a silylated
multifunctional anhydride, and wherein the at least one of the
epoxy functional silane and the diol functional organopolysiloxane
is present in a molar ratio to the multifunctional crosslinker from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane, the diol functional
organopolysiloxane, and the silylated multifunctional
crosslinker.
[0007] In one example, the at least one of the epoxy functional
silane and the diol functional organopolysiloxane is present in a
molar ratio to the multifunctional crosslinker of about 2:1 to 1:2.
In another example, the coating can be formed to a radius from
about 1 inch to less than about 10 inches on a polycarbonate
substrate. In a further example, the coating can be formed to a
radius from about 3 inches to about 5 inches on a polycarbonate
substrate.
[0008] In another example, the coating has a Taber number of less
than about 10 percent after 50 revolutions of a Taber wheel or a
Taber number of less than about 2 percent after 50 revolutions of a
Taber wheel. In another example, the coating has a Taber number of
less than about 45 percent after 200 revolutions of a Taber wheel
or a Taber number of less than about 15 percent after 200
revolutions of a Taber wheel.
[0009] In one example, the at least one of the epoxy functional
silane and the diol functional organopolysiloxane comprises about 5
to about 93 percent by weight of the solids of the composition, and
the multifunctional crosslinker comprises about 7 to about 95
percent by weight of the solids of the composition. In another
example, the at least one of the epoxy functional silane and the
diol functional silane comprises about 30 to about 70 percent by
weight of the solids of the composition, and the multifunctional
crosslinker comprises about 30 to about 70 percent by weight of the
solids of the composition. In a further example, the solvent
constituent of the aqueous-organic solvent mixture comprises from
about 40 to about 98 percent by weight of the composition. In yet
another example, the solvent constituent of the aqueous-organic
solvent mixture comprises from about 65 to about 95 percent by
weight of the composition.
[0010] In one example, the solvent constituent of the
aqueous-organic solvent mixture is selected from an ether, a glycol
or a glycol ether, a ketone, an ester, a glycolether acetate, and
combinations thereof. In another example, the solvent constituent
of the aqueous-organic solvent mixture is selected from alcohols
having the formula ROH where R is an alkyl group containing from 1
to about 10 carbon atoms. In another example, the solvent
constituent of the aqueous-organic solvent mixture is selected from
glycols, ethers, glycol ethers having the formula
R.sup.1--(OR.sup.2).sub.xOR.sup.1 where x is 0, 1, 2, 3 or 4,
R.sup.1 is hydrogen or an alkyl group containing from 1 to about 10
carbon atoms and R.sup.2 is an allylene group containing from 1 to
about 10 carbon atoms and combinations thereof.
[0011] In one example, the epoxy functional silane is represented
by the formula R.sup.3.sub.xSi(OR.sup.4).sub.4-x, wherein: x is an
integer of 1, 2 or 3; R.sup.3 is H, an alkyl group, a
functionalized allyl group, an alkylene group, an aryl group, an
alkyl ether, and combinations thereof containing from 1 to about 10
carbon atoms and having at least 1 epoxy functional group; R.sup.4
is H, an alkyl group containing from 1 to about 5 carbon atoms, an
acetyl group, a --Si(OR.sup.5).sub.3-7R.sup.6.sub.y group where y
is an integer of 0, 1, 2, or 3, and combinations thereof; R.sup.5
is H, an alkyl group containing from 1 to about 5 carbon atoms, an
acetyl group, or another --Si(OR.sup.5).sub.3-yR.sup.6.sub.y group
and combinations thereof; and R.sup.6 is H, an alkyl group, a
functionalized alkyl group, an alkylene group, an aryl group, an
alkyl ether, and combinations thereof containing from 1 to about 10
carbon atoms.
[0012] In one example, the aqueous-organic solvent mixture further
comprises an effective amount of a leveling agent to spread the
aqueous-organic solvent mixture on the substrate and provide a
substantially uniform contact of the aqueous-organic solvent
mixture with the substrate. In another example, the composition
further comprises at least one catalyst, at least one ultraviolet
stabilizer, or at least one surfactant, and combinations
thereof.
[0013] In other embodiments of the present invention, compositions
which, when applied to a substrate and cured, provide an abrasion
resistant formable coating on the substrate are provided. The
compositions can comprise an aqueous-organic solvent mixture having
hydrolysis products and partial condensates of a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein the diol
functional organopolysiloxane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the diol functional
organopolysiloxane and the silylated multifunctional crosslinker.
In one example, the aqueous-organic solvent mixture further
comprises hydrolysis products and partial condensates of an epoxy
functional silane and the at least one multifunctional
crosslinker.
[0014] In accordance with further embodiments of the present
invention, compositions which, when applied to a substrate and
cured, provide an abrasion resistant formable coating on the
substrate are provided. The compositions can comprise an
aqueous-organic solvent mixture having hydrolysis products and
partial condensates of an epoxy functional silane and at least one
multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the at least one epoxy functional silane is
present in a molar ratio to the multifunctional crosslinker of from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane and the silylated multifunctional
crosslinker, wherein the composition contains an amount of at least
one of tetrafunctional silanes, disilanes, and alkyl silanes
insufficient to render the coating rigid on the substrate. In one
example, the aqueous-organic solvent mixture further comprises
hydrolysis products and partial condensates of a diol functional
organopolysiloxane and the multifunctional crosslinker.
[0015] In accordance with embodiments of the present invention,
compositions which, when applied to a substrate and cured, provide
an abrasion resistant formable coating on the substrate are
provided. The compositions can comprise an aqueous-organic solvent
mixture having hydrolysis products and partial condensates of an
epoxy functional silane at and least one multifunctional
crosslinker, wherein the multifunctional crosslinker is selected
from multifunctional carboxylic acids, multifunctional anhydrides,
and silylated multifunctional anhydrides, and wherein the epoxy
functional silane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to about 1:10; an
amount of water sufficient to hydrolyze the epoxy functional silane
and the silylated multifunctional crosslinker; and at least one of
a tetrafunctional silane and a disilane, wherein the epoxy
functional silane is present in a molar ratio to the at least one
of the tetrafunctional silane and the disilane of at least about
5.5:1. In one example, the aqueous-organic solvent mixture further
comprises hydrolysis products and partial condensates of a diol
functional organopolysiloxane and the multifunctional
crosslinker.
[0016] In another example, the tetrafunctional silane has a formula
of Si(OR.sup.9).sub.4, where R.sup.9 is H, an alkyl group
containing from 1 to about 5 carbon atoms and ethers thereof, an
(OR.sup.9) carboxylate, a --Si(OR.sup.10).sub.3 group where
R.sup.10 is a H, an alkyl group containing from 1 to about 5 carbon
atoms and ethers thereof, an (OR.sup.10) carboxylate, or another
--Si(OR.sup.10).sub.3 group and combinations thereof. In a further
example, the disilane has a formula of
(R.sup.11O).sub.xR.sup.12.sub.3-xSi--R.sup.13.sub.y--SiR.sup.14.sub.3-x(O-
R.sup.15).sub.x; wherein x is 0, 1, 2, or 3 and y is 0 or 1;
wherein R.sup.12 and R.sup.14 comprises H, an alkyl group
containing from about 1 to about 10 carbon atoms, a functionalized
alkyl group, an allylene group, an aryl group, an alkypolyether
group, and combinations thereof; wherein R.sup.11 and R.sup.15
comprises H, an alkyl group containing from about 1 to about 10
carbon atoms, an acetyl group, and combinations thereof; wherein if
y is 1 then R.sup.13 comprises an allylene group containing from
about 1 to about 12 carbon atoms, an alkylenepolyether containing
from about 1 to about 12 carbon atoms, an aryl group, an allylene
substituted aryl group, an allylene group which may contain one or
more olefins, S, or O; wherein if x is 0 then R.sup.12 and R.sup.14
comprises Cl or Br; and wherein if y is 0 then there is a direct
silicon-silicon bond.
[0017] In accordance with embodiments of the present invention
compositions which, when applied to a substrate and cured, provide
an abrasion resistant formable coating on the substrate are
provided. The compositions can comprise an aqueous-organic solvent
mixture having hydrolysis products and partial condensates of an
epoxy functional silane at least one multifunctional crosslinker,
wherein the multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein the epoxy
functional silane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to about 1:10; an
amount of water sufficient to hydrolyze the epoxy functional silane
and the silylated multifunctional crosslinker; and at least one
alkyl silane, wherein the epoxy functional silane is present in a
molar ratio to the at least one allyl silane of at least about
2.5:1.
[0018] In one example, the aqueous-organic solvent mixture further
comprises hydrolysis products and partial condensates of a diol
functional organopolysiloxane and the multifunctional crosslinker.
In another example, the allyl silane has a formula of
R.sup.16.sub.xSi(OR.sup.17).sub.4-x, where x is a number of 1, 2 or
3; R.sup.16 is H, or an allyl group containing from 1 to about 10
carbon atoms, a functionalized allyl group, an allylene group, an
aryl group an alkoxypolyether group and combinations thereof;
R.sup.17 is H, an allyl group containing from 1 to about 10 carbon
atoms, an acetyl group; and combinations thereof.
[0019] In accordance with other embodiments of the present
invention, compositions which, when applied to a substrate and
cured, provide an abrasion resistant and formable coating on the
substrate are provided. The compositions can comprise an
aqueous-organic solvent mixture having hydrolysis products and
partial condensates of at least one epoxy functional silane and at
least one multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the at least one epoxy functional silane is
present in a molar ratio to the multifunctional crosslinker from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane and the silylated multifunctional
crosslinker, wherein the composition does not contain
tetrafunctional silanes, disilanes, and alkyl silanes. In one
example, the aqueous-organic solvent mixture further comprises
hydrolysis products and partial condensates of a diol functional
organopolysiloxane and the multifunctional crosslinker.
[0020] In accordance with embodiments of the present invention,
articles are provided. The articles can comprise a substrate and an
abrasion resistant formable coating present on at least one surface
of the substrate by curing a coating composition, comprising: an
aqueous-organic solvent mixture having hydrolysis products and
partial condensates of at least one of an epoxy functional silane
and a diol functional organopolysiloxane and at least one
multifunctional crosslinker, wherein the multifunctional
crosslinker comprises a silylated multifunctional anhydride, and
wherein the at least one of the epoxy functional silane and the
diol functional organopolysiloxane is present in a molar ratio to
the multifunctional crosslinker from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional
silane, the diol functional organopolysiloxane, and the silylated
multifunctional crosslinker. In one example, at least one primer
disposed on the at least one surface of the substrate between the
substrate and the coating.
[0021] In accordance with further embodiments of the present
invention, articles are provided. The articles can comprise a
substrate and an abrasion resistant formable coating present on at
least one surface of the substrate by curing a coating composition,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein the at least one
diol functional organopolysiloxane is present in a molar ratio to
the multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the diol functional
organopolysiloxane and the silylated multifunctional
crosslinker.
[0022] In accordance with other embodiments of the present
invention, articles are provided. The articles can comprise a
substrate and an abrasion resistant formable coating present on at
least one surface of the substrate by curing a coating composition,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane and
at least one multifunctional crosslinker, wherein the
multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein the at least one epoxy
functional silane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional silane
and the silylated multifunctional crosslinker, wherein the
composition contains an amount of at least one of tetrafunctional
silanes, disilanes, and alkyl silanes insufficient to render the
coating rigid on the substrate.
[0023] In accordance with embodiments of the present invention,
articles are provided. The articles can comprise a substrate and an
abrasion resistant formable coating present on at least one surface
of the substrate by curing a coating composition, comprising: an
aqueous-organic solvent mixture having hydrolysis products and
partial condensates of an epoxy functional silane at least one
multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the epoxy functional silane is present in a
molar ratio to the multifunctional crosslinker of from about 10:1
to about 1:10; an amount of water sufficient to hydrolyze the epoxy
functional silane and the silylated multifunctional crosslinker;
and at least one of a tetrafunctional silane and a disilane,
wherein the epoxy functional silane is present in a molar ratio to
the at least one of the tetrafunctional silane and the disilane of
at least about 5.5:1.
[0024] In accordance with further embodiments of the present
invention, articles are provided. The articles can comprise a
substrate and an abrasion resistant formable coating present on at
least one surface of the substrate by curing a coating composition,
comprising: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane at
least one multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the epoxy functional silane is present in a
molar ratio to the multifunctional crosslinker of from about 10:1
to about 1:10; an amount of water sufficient to hydrolyze the epoxy
functional silane and the silylated multifunctional crosslinker;
and at least one allyl silane, wherein the epoxy functional silane
is present in a molar ratio to the at least one allyl silane of at
least about 2.5:1.
[0025] In accordance with embodiments of the present invention,
articles are provided. The articles can comprise a substrate and an
abrasion resistant formable coating present on at least one surface
of the substrate by curing a coating composition, comprising: an
aqueous-organic solvent mixture having hydrolysis products and
partial condensates of at least one epoxy functional silane and at
least one multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the at least one epoxy functional silane is
present in a molar ratio to the multifunctional crosslinker from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane and the silylated multifunctional
crosslinker, wherein the composition does not contain
tetrafunctional silanes, disilanes, and alkyl silanes.
[0026] In accordance with embodiments of the present invention,
formed articles are provided. The articles can comprise a formed
substrate and an abrasion resistant formable coating present on at
least one surface of the substrate by applying a coating
composition, curing the coating composition, and subsequently
forming the substrate, wherein the coating composition comprises:
an aqueous-organic solvent mixture having hydrolysis products and
partial condensates of at least one of an epoxy functional silane
and a diol functional organopolysiloxane and at least one
multifunctional crosslinker, wherein the multifunctional
crosslinker comprises a silylated multifunctional anhydride, and
wherein the at least one of the epoxy functional silane and the
diol functional organopolysiloxane is present in a molar ratio to
the multifunctional crosslinker from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional
silane, the diol functional organopolysiloxane, and the silylated
multifunctional crosslinker. In one example, the formed article
further comprises at least one primer disposed on the at least one
surface of the substrate between the substrate and the coating.
[0027] In accordance with further embodiments of the present
invention, formed articles are provided. The formed articles can
comprise a formed substrate and an abrasion resistant formable
coating present on at least one surface of the substrate by
applying a coating composition, curing the coating composition, and
subsequently forming the substrate, wherein the coating composition
comprises: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein the at least one
diol functional organopolysiloxane is present in a molar ratio to
the multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the diol functional
organopolysiloxane and the silylated multifunctional
crosslinker.
[0028] In accordance with other embodiments of the present
invention, formed articles are provided. The formed articles can
comprise a formed substrate and an abrasion resistant formable
coating present on at least one surface of the substrate by
applying a coating composition, curing the coating composition, and
subsequently forming the substrate, wherein the coating composition
comprises: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane and
at least one multifunctional crosslinker, wherein the
multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein the at least one epoxy
functional silane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional silane
and the silylated multifunctional crosslinker, wherein the
composition contains an amount of at least one of tetrafunctional
silanes, disilanes, and alkyl silanes insufficient to render the
coating rigid on the substrate.
[0029] In accordance with embodiments of the present invention,
formed articles are provided. The articles can comprise a formed
substrate and an abrasion resistant formable coating present on at
least one surface of the substrate by applying a coating
composition, curing the coating composition, and subsequently
forming the substrate, wherein the coating composition comprises:
an aqueous-organic solvent mixture having hydrolysis products and
partial condensates of an epoxy functional silane at least one
multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the epoxy functional silane is present in a
molar ratio to the multifunctional crosslinker of from about 10:1
to about 1:10; an amount of water sufficient to hydrolyze the epoxy
functional silane and the silylated multifunctional crosslinker;
and at least one of a tetrafunctional silane and a disilane,
wherein the epoxy functional silane is present in a molar ratio to
the at least one of the tetrafunctional silane and the disilane of
at least about 5.5:1.
[0030] In accordance with other embodiments of the present
invention, formed articles are provided. The formed articles
comprise a formed substrate and an abrasion resistant formable
coating present on at least one surface of the substrate by
applying a coating composition, curing the coating composition, and
subsequently forming the substrate, wherein the coating composition
comprises: an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of an epoxy functional silane at
least one multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the epoxy functional silane is present in a
molar ratio to the multifunctional crosslinker of from about 10:1
to about 1:10; an amount of water sufficient to hydrolyze the epoxy
functional silane and the silylated multifunctional crosslinker;
and at least one allyl silane, wherein the epoxy functional silane
is present in a molar ratio to the at least one alkyl silane of at
least about 2.5:1.
[0031] In accordance with embodiments of the present invention,
formed articles are provided. The formed articles can comprise a
formed substrate and an abrasion resistant formable coating present
on at least one surface of the substrate by applying a coating
composition, curing the coating composition, and subsequently
forming the substrate, wherein the coating composition comprises:
an aqueous-organic solvent mixture having hydrolysis products and
partial condensates of at least one epoxy functional silane and at
least one multifunctional crosslinker, wherein the multifunctional
crosslinker is selected from multifunctional carboxylic acids,
multifunctional anhydrides, and silylated multifunctional
anhydrides, and wherein the at least one epoxy functional silane is
present in a molar ratio to the multifunctional crosslinker from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane and the silylated multifunctional
crosslinker, wherein the composition does not contain
tetrafunctional silanes, disilanes, and alkyl silanes.
[0032] In accordance with embodiments of the present invention
processes for providing abrasion resistant formable coatings are
provided. The processes can comprise applying a coating composition
to a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of at least one
of an epoxy functional silane and a diol functional
organopolysiloxane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker comprises a silylated
multifunctional anhydride, and wherein the at least one of the
epoxy functional silane and the diol functional organopolysiloxane
is present in a molar ratio to the multifunctional crosslinker from
about 10:1 to 1:10; and an amount of water sufficient to hydrolyze
the epoxy functional silane, the diol functional
organopolysiloxane, and the silylated multifunctional crosslinker.
In one example, the process further comprises the step of forming
the coated substrate. In another example, the process further
comprises applying a primer to the substrate prior to applying the
coating composition to the substrate on the primer.
[0033] In accordance with embodiments of the present invention,
processes for providing an abrasion resistant formable coatings are
provided. The processes comprise applying a coating composition to
a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of a diol
functional organopolysiloxane and at least one multifunctional
crosslinker, wherein the multifunctional crosslinker is selected
from multifunctional carboxylic acids, multifunctional anhydrides,
and silylated multifunctional anhydrides, and wherein the at least
one diol functional organopolysiloxane is present in a molar ratio
to the multifunctional crosslinker of from about 10:1 to 1:10; and
an amount of water sufficient to hydrolyze the diol functional
organopolysiloxane and the silylated multifunctional
crosslinker.
[0034] In accordance with embodiments of the present invention,
processes for providing an abrasion resistant formable coatings are
provided. The processes can comprise applying a coating composition
to a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of an epoxy
functional silane and at least one multifunctional crosslinker,
wherein the multifunctional crosslinker is selected from
multifunctional carboxylic acids, multifunctional anhydrides, and
silylated multifunctional anhydrides, and wherein the at least one
epoxy functional silane is present in a molar ratio to the
multifunctional crosslinker of from about 10:1 to 1:10; and an
amount of water sufficient to hydrolyze the epoxy functional silane
and the silylated multifunctional crosslinker, wherein the
composition contains an amount of at least on of tetrafunctional
silanes, disilanes, and alkyl silanes insufficient to render the
coating rigid on the substrate.
[0035] In accordance with embodiments of the present invention,
processes for providing an abrasion resistant formable coatings are
provided. The processes comprise applying a coating composition to
a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of an epoxy
functional silane at least one multifunctional crosslinker, wherein
the multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein the epoxy functional silane
is present in a molar ratio to the multifunctional crosslinker of
from about 10:1 to about 1:10; an amount of water sufficient to
hydrolyze the epoxy functional silane and the silylated
multifunctional crosslinker; and at least one of a tetrafunctional
silane and a disilane, wherein the epoxy functional silane is
present in a molar ratio to the at least one of the tetrafunctional
silane and the disilane of at least about 5.5:1.
[0036] In accordance with embodiments of the present invention,
processes for providing an abrasion resistant formable coatings are
provided. The processes comprise applying a coating composition to
a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of an epoxy
functional silane at least one multifunctional crosslinker, wherein
the multifunctional crosslinker is selected from multifunctional
carboxylic acids, multifunctional anhydrides, and silylated
multifunctional anhydrides, and wherein the epoxy functional silane
is present in a molar ratio to the multifunctional crosslinker of
from about 10:1 to about 1:10; an amount of water sufficient to
hydrolyze the epoxy functional silane and the silylated
multifunctional crosslinker; and at least one alkyl silane, wherein
the epoxy functional silane is present in a molar ratio to the at
least one allyl silane of at least about 2.5:1.
[0037] In accordance with embodiments of the present invention,
processes for providing an abrasion resistant formable coatings are
provided. The processes comprise applying a coating composition to
a substrate; and curing the coating composition, wherein the
coating composition comprises: an aqueous-organic solvent mixture
having hydrolysis products and partial condensates of at least one
epoxy functional silane and at least one multifunctional
crosslinker, wherein the multifunctional crosslinker is selected
from multifunctional carboxylic acids, multifunctional anhydrides,
and silylated multifunctional anhydrides, and wherein the at least
one epoxy functional silane is present in a molar ratio to the
multifunctional crosslinker from about 10:1 to 1:10; and an amount
of water sufficient to hydrolyze the epoxy functional silane and
the silylated multifunctional crosslinker, wherein the composition
does not contain tetrafunctional silanes, disilanes, and alkyl
silanes.
[0038] It will be understood that various changes may be made
without departing from the scope of the invention, which is not to
be considered limited to what is described in the description.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0039] The present invention will now be described with occasional
reference to specific embodiments of the invention. This invention
may, however, be embodied in different forms and should not be
construed as limited to the embodiments set forth herein. Rather,
these embodiments are provided so that this disclosure will be
thorough and complete.
[0040] Unless otherwise defined, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. The
terminology used in the description of the invention herein is for
describing particular embodiments only and is not intended to be
limiting of the invention. As used in the description of the
invention and the appended claims, the singular forms "a," "an,"
and "the" are intended to include the plural forms as well, unless
the context clearly indicates otherwise. All publications, patent
applications, patents, and other references mentioned herein are
incorporated by reference in their entirety.
[0041] Unless otherwise indicated, all numbers expressing
quantities of ingredients, properties such as molecular weight,
reaction conditions, and so forth as used in the description and
claims are to be understood as being modified in all instances by
the term "about." Accordingly, unless otherwise indicated, the
numerical properties set forth in the following description and
claims are approximations that may vary depending on the desired
properties sought to be obtained in embodiments of the present
invention. Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical values, however,
inherently contain certain errors necessarily resulting from error
found in their respective measurements.
[0042] The present invention relates to stable coating compositions
which, when applied to a variety of substrates and cured, form
abrasion resistant, formable coatings. For purposes of defining and
describing the present invention, the term "stable" shall be
understood as referring to coating compositions that are useable
for an amount of time suitable for a particular application. In
addition, the present invention relates to coated articles, formed
coated articles, and methods of forming coated articles. The coated
articles can be formed in any suitable manner. For example, the
coated articles can be thermoformed. "Thermoforming" is a well
known term in the plastics art describing the process of shaping
thermoplastic sheets by heating them until softened, then forming
the softened sheets into desired shapes using any suitable
procedure such as molding, jigging, or vacuum forming.
[0043] In accordance with embodiments of the present invention, a
stable coating composition that forms an abrasion resistant,
formable coating is provided. The coating composition is cured to
form a transparent coating on a substrate. The coating composition
comprises an aqueous-organic solvent mixture having hydrolysis
products and partial condensates of at least one of at least one
epoxy functional silane and at least one diol functional
organopolysiloxane, or combinations thereof and at least one
multifunctional crosslinker to form a cured organopolysiloxane
coating on a substrate. The at least one of the epoxy functional
silane and the diol functional organopolysiloxane is present in a
molar ratio to the multifunctional crosslinker of between about
10:1 to about 1:10. In one example, the at least one of the epoxy
functional silane and the diol functional organopolysiloxane can be
present in a molar ratio to the multifunctional crosslinker of
about 2:1 to about 1:2.
[0044] In one example, the multifunctional crosslinker is selected
from multifunctional carboxylic acids, multifunctional anyhydrides,
silylated multifunctional carboxylic acids, and silylated
multifunctional anyhydrides, and combinations thereof. In another
example, the multifunctional crosslinker is at least one silylated
multifunctional anhydride or at least one silylated multifunctional
carboxylic acid. The coating composition also contains an amount of
water sufficient to hydrolyze the at least one of the epoxy
functional silane and the diol functional organopolysiloxane and
the silylated multifunctional crosslinker.
[0045] The solvent component of the aqueous-organic solvent mixture
can be present in any suitable amount. For example, the solvent
component of the aqueous-organic solvent mixture comprises about 40
to about 98 percent of the coating composition by weight. In
another example, the solvent component of the aqueous-organic
solvent mixture comprises about 65 to about 95 percent of the
coating composition by weight. It will be understood by those
having skill in the art that at least a part of the solvent
component of the aqueous-organic solvent mixture can be formed as
hydrolysis by-products of the reactions of the coating
compositions. The at least one of the epoxy functional silane and
diol functional organopolysiloxane can be present in any suitable
amount. For example, the at least one of the epoxy functional
silane and diol functional organopolysiloxane comprises about 5 to
about 93 percent by weight of the total solids of the composition.
In another example, the at least one of the epoxy functional silane
and diol functional organopolysiloxane comprises about 30 to about
70 percent by weight of the total solids of the coating
composition. The multifunctional crosslinker can be present in any
suitable amount. In one example, the multifunctional crosslinker
comprises about 7 to about 95 percent by weight of the total solids
of the composition. In another example, the multifunctional
crosslinker comprises about 30 to about 70 percent by weight of the
total solids of the coating composition.
[0046] In another embodiment of the present invention, the coating
composition may include tetrafunctional silanes, disilanes, or
other alkyl silanes that are not epoxy functional. However, the
tetrafunctional silanes, disilanes, and other alkyl silanes are
present in amounts insufficient to render the cured coating rigid.
For purposes of defining and describing the present invention, the
term "rigid" shall be understood as referring to coatings that are
not formable as defined herein. In one example, the coating
composition has a molar ratio of the at least one epoxy functional
silane to tetrafunctional silane of at least about 5.5:1. In a
further example, the coating composition has a molar ratio of she
at least one epoxy functional silane to disilane of at least about
5.5:1. In another example, the coating composition has a molar
ratio of the at least one epoxy functional silane to allyl silane
of at least about 2.5:1. The amount of tetrafunctional silanes,
disilanes, and other allyl silanes that are not epoxy functional
that are incorporated into the coating compositions of the present
invention can vary widely and will generally depend on the desired
properties of the cured coating produced from the coating
compositions, as well as the desired stability of the coating
compositions. The tetrafunctional silanes, disilanes, and the alkyl
silanes that are not epoxy functional can improve abrasion
resistance, chemical resistance, and the optical properties of the
cured coatings. In other embodiments of the present invention, the
coating composition may include other additives such as anti-fog
components, leveling agents, catalysts, etc., as will be further
described herein.
[0047] For testing abrasion resistance of coated substrates, any of
a number of quantitative test methods may be employed, including
the Taber Test (ASTM D-4060), the Tumble Test, and the Oscillating
Sand Test (ASTM F735-81). In addition, there are a number of
qualitative test methods that may be used for measuring abrasion
resistance, including the Steel Wool Test and the Eraser Test. In
the Steel Wool Test and the Eraser Test, sample coated substrates
are scratched under reproducible conditions (constant load,
frequency, etc.). The scratched test samples are then compared and
rated against standard samples. A semi-quantitative application of
these test methods involves the use of an instrument, such as a
Spectrophotometer or a Colorimeter, for measuring the scratches on
the coated substrate as a haze gain.
[0048] The measured abrasion resistance of a cured coating on a
substrate, whether measured by the Taber Test, Steel Wool Test,
Eraser Test, Tumble Test, etc. is a function, in part, of the cure
temperature and cure time. In general, higher temperatures and
longer cure times result in higher measured abrasion resistance.
Normally, the cure temperature and cure time are selected for
compatibility with the substrate. However, sometimes less than
optimum cure temperatures and cure times are used due to process
and/or equipment limitations. It will be recognized by those
skilled in the art that other variables, such as coating thickness
and the nature of the substrate, will also have an effect on the
measured abrasion resistance. In general, for each type of
substrate and for each coating composition there will be an optimum
coating thickness. The optimum cure temperature, cure time, coating
thickness, and the like, can be readily determined empirically by
those skilled in the art.
[0049] The Taber Abrasion test is performed with a Teledyne Model
5150 Taber Abrader (Taber Industries, North Tonawanda, N.Y.) with a
500 g auxiliary load weight and with CS-10F wheels (Taber
Industries, North Tonawanda, N.Y.). Prior to the measurement, the
wheels are refaced with the ST-11 refacing stone (Taber Industries,
North Tonawanda, N.Y.). The refacing is performed by 25 revolutions
of the CS-10F wheels on the refacing stone. The initial haze of the
sample is recorded 4 times with a Haze-gard Plus (BYK-Gardner,
Columbia, Md.) equipped with a Taber Abrasion holder (BYK-Gardner,
Columbia, Md.). After 50 cycles of the CS-10F wheels on the sample,
the haze is recorded again 4 times with a Haze-gard Plus
(BYK-Gardner, Columbia, Md.) equipped with a Taber Abrasion holder
(BYK-Gardner, Columbia, Md.). The average haze is then determined
for the initial haze reading, the haze reading after 50 cycles, and
after 200 cycles using the new CS-10F wheels available at least as
early as July 2003. The difference between the averaged haze
readings at 50 and 200 cycles and the initial haze reading is then
reported.
[0050] The Taber method is considered a semi-quantitative method
for measuring abrasion resistance. The precision and accuracy of
the method is dependent on a number of factors, including the
condition of the CS-10F test wheels. Changes in the condition of
the CS-10F test wheels can have a significant affect on the outcome
of an abrasion resistance test. For example, a recent change made
by Taber Industries in the composition of the CS-10F wheels changed
the haze gain on standard samples from 1% haze and 5% haze at 100
and 500 cycles (reported as 1%/5%) respectively, to 7% and 25%,
respectively. Throughout the testing conducted herein, all of the
samples were tested with the same set of new CS-10F Taber wheels.
In accordance with embodiments of the present invention, the
coatings can have Taber numbers of less than about 30%, less than
about 10%, or less than about 5% for 50 cycles. In accordance with
other embodiments of the present invention, the coatings can have
Taber numbers of less than about 2% for 50 cycles. In other
examples, the coatings can have Taber numbers of less than about
45%, less than about 30%, or less than about 15% for 200
cycles.
[0051] The formability of the coatings can be tested in the
following manner. An oven with a glass plate is preheated to
165.degree. C. A 2''.times.7'' coated 1/4'' Lexan polycarbonate
(1/4'' Lexan PC, Regal Plastics, Santa Fe Springs, Calif.) test
sample is placed flat on the glass plate and heated at 165.degree.
C. for 18 min. The thickness of the coating can be from about 1-20
microns or about 2-10 microns. The sample is removed from the oven
and immediately placed on a cylindrical mandrel. The formability of
the sample is rated by determining the minimal radius of the
mandrel where no cracking, flaking, or detachment of the coating is
observed. For purposes of defining and describing the present
invention, the terms "formable" and "formability" shall be
understood as referring to cured coatings that can be bent at a
radius of less than about 10 inches, in accordance with the above
procedure. In one example, the cured coatings can be bent at a
radius of between about 3 to about 5 inches in accordance with the
above procedure without cracking or crazing of the coating.
[0052] The presence of water in an aqueous-organic solvent mixture
is needed to form hydrolysis products of the silane components of
the mixture. The actual amount of water can vary widely. Enough
water is needed to provide a suitably homogeneous coating mixture
of hydrolysis products and partial condensates of the silane
components of the coating composition with the other added
components. It will be recognized by those skilled in the art that
this amount of water can be determined empirically.
[0053] The solvent constituent of the aqueous-organic solvent
mixture of the coating compositions of the present invention can be
any solvent or combination of solvents which are compatible with
the components of the coating composition including, but not
limited to, an epoxy functional silane, diol functional
organopolysiloxane, a silane which is not epoxy functional, a
tetrafunctional silane, a disilane, and a multi-functional
crosslinker, or any combinations thereof. For example, the solvent
constituent of the aqueous-organic solvent mixture may be water, an
alcohol, an ether, a glycol or a glycol ether, a ketone, an ester,
a glycolether acetate, and combinations thereof. Suitable alcohols
can be represented by the formula ROH where R is an alkyl group
containing from 1 to about 10 carbon atoms. Some examples of
alcohols useful in the application of this invention are methanol,
ethanol, propanol, isopropanol, butanol, isobutanol, secondary
butanol, tertiary butanol, cyclohexanol, pentanol, octanol,
decanol, and mixtures thereof.
[0054] Suitable glycols, ethers, glycol ethers can be represented
by the formula R.sup.1--(OR.sup.2).sub.x--OR.sup.1 where x is 0, 1,
2, 3 or 4, R.sup.1 is hydrogen or an alkyl group containing from 1
to about 10 carbon atoms and R.sup.2 is an allylene group
containing from 1 to about 10 carbon atoms and combinations
thereof.
[0055] Examples of glycols, ethers and glycol ethers having the
above defined formula include, but are not limited to,
di-n-butylether, ethylene glycol dimethyl ether, propylene glycol
dimethyl ether, propylene glycol methyl ether, dipropylene glycol
methyl ether, tripropylene glycol methyl ether, dipropylene glycol
dimethyl ether, tripropylene glycol dimethyl ether, ethylene glycol
butyl ether, diethylene glycol butyl ether, ethylene glycol dibutyl
ether, ethylene glycol methyl ether, diethylene glycol ethyl ether,
diethylene glycol dimethyl ether, ethylene glycol ethyl ether,
ethylene glycol diethyl ether, ethylene glycol, diethylene glycol,
triethylene glycol, propylene glycol, dipropylene glycol,
tripropylene glycol, butylene glycol, dibutylene glycol,
tributylene glycol and combinations thereof. In addition to the
above, cyclic ethers such as tetrahydrofuran and dioxane are
suitable ethers for the aqueous-organic solvent mixture.
[0056] Examples of ketones suitable for the aqueous-organic solvent
mixture include, but are not limited to, acetone, diacetone
alcohol, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone
and combinations thereof. Examples of esters suitable for the
aqueous-organic solvent mixture include, but are not limited to,
ethyl acetate, n-propyl acetate, n-butyl acetate and combinations
thereof. Examples of glycolether acetates suitable for the
aqueous-organic solvent mixture include, but are not limited to,
propylene glycol methyl ether acetate, dipropylene glycol methyl
ether acetate, ethyl 3-ethoxyproprionate, ethylene glycol ethyl
ether acetate and combinations thereof.
[0057] Any suitable epoxy functional silane, diol functional
organopolysiloxane from a hydrolyzed epoxy functional silane, or
combinations thereof can be used in the coating compositions of the
present invention. For example, the epoxy functional silane or diol
functional organopolysiloxane can be any epoxy functional silane or
diol functional organopolysiloxane which is compatible with the
multifunctional carboxylic acid. For example, such epoxy functional
silanes are represented by the formula
R.sup.3.sub.xSi(OR.sup.4).sub.4-x where x is an integer of 1, 2 or
3, R.sup.3 is H, an alkyl group, a functionalized allyl group, an
alkylene group, an aryl group, an alkyl ether, and combinations
thereof containing from 1 to about 10 carbon atoms and having at
least 1 epoxy functional group, and R.sup.4 is H, an alkyl group
containing from 1 to about 5 carbon atoms, an acetyl group, a
--Si(OR.sup.5).sub.3-yR.sup.6.sub.y group where y is an integer of
0, 1, 2, or 3, and combinations thereof where R.sup.5 is H, an
alkyl group containing from 1 to about 5 carbon atoms, an acetyl
group, or another --Si(OR.sup.5).sub.3-yR.sup.6.sub.y group and
combinations thereof, and R.sup.6 is H, an alkyl group, a
functionalized alkyl group, an alkylene group, an aryl group, an
allyl ether, and combinations thereof containing from 1 to about 10
carbon atoms which may also contain an epoxy functional group.
[0058] In another example, the diol functional organopolysiloxane
is the product of a ring-opening reaction of epoxy functional
silane with water. The ring-opening reaction is accompanied by
hydrolysis and condensation of the alkoxy groups. Such a
ring-opening reaction is graphically shown as:
##STR00001##
where R is any suitable group. In another example, a commercial
source of a diol functional organopolysiloxane, HS2926, can be
obtained from DEGUSSA Corp.(Piscataway, N.J.). The HS2926 can be
used "as-is" without further purification. Diol functional
organopolysiloxanes can be prepared by mixing an epoxy functional
silane with an excess of water that is adjusted to a pH of three
with acid and refluxed for several hours. The alcohol that forms
during the hydrolysis of the alkoxysilane groups can be removed by
distillation.
[0059] Examples of suitable epoxy functional silanes include, but
are not limited to, glycidoxymethyltrimethoxysilane,
3-glycidoxypropyltrihydroxysilane, 3-glycidoxypropyl
dimethylhydroxysilane, 3-glycidoxypropyltrimethoxysilane,
3-glycidoxypropyltriethoxysilane,
3-glycidoxypropyldimethoxymethylsilane,
3-glycidoxypropyldimethylmethoxysilane,
3-glycidoxypropyltributoxysilane,
1,3-bis(glycidoxypropyl)tetramethyldisiloxane,
1,3-bis(glycidoxypropyl)tetramethoxydisiloxane,
[0060]
1,3-bis(glycidoxypropyl)-1,3-dimethyl-1,3-dimethoxydisiloxane,
[0061] 2,3-epoxypropyltrimethoxysilane,
3,4-epoxybutyltrimethoxysilane, 6,7-epoxyheptyltrimethoxysilane,
9,10-epoxydecyltrimethoxysilane,
1,3-bis(2,3-epoxypropyl)tetramethoxydisiloxane,
1,3-bis(6,7-epoxy-heptyl)tetramethoxydisiloxane,
2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and the like.
[0062] Any suitable multifunctional crosslinker or combinations of
multifunctional crosslinkers can be used in the present invention.
The multifunctional crosslinker can be any multifunctional
carboxylic acid, multifunctional anhydride, silylated
multifunctional anhydride, silylated multifunctional carboxylic
acid, and combinations thereof which are compatible with epoxy
functional silanes, diol functional organopolysiloxanes, or other
components of the coating compositions. Silylated multifunctional
anhydrides and carboxylic acids have --Si(OR') groups that are
capable of interacting with the hydrolysis products and partial
condensates of epoxy functional silanes, diol functional
organopolysiloxanes, tetrafunctional silanes, disilanes, and alkyl
silanes.
[0063] The multifunctional crosslinker can include, but is not
limited to, multifunctional carboxylic acids as well as anhydrides
which produce multifunctional carboxylic acids. The carboxylic acid
functional compound can be represented by the formula
R.sup.7(COOR.sup.8).sub.x, where x is an integer of 1, 2, 3, or 4,
and where R.sup.7 is selected from the group consisting of H, an
alkyl group, a functionalized alkyl group, an alkylene group, an
aryl group, a functionalized aryl group, an alkyl ether, and
combinations thereof wherein each of the allyl group, the alkylene
group, the aryl group, the functionalized alkyl group, and the
alkyl ether are further characterized as containing from 1 to about
10 carbon atoms, and where R.sup.8 is selected from the group
consisting of H, a formyl group, a carbonyl group, or an acyl
group, where the acyl group can be functionalized with an alkyl
group, a functionalized alkyl group, an alkylene group, an aryl
group, a functionalized aryl group, an alkyl ether, and
combinations thereof wherein each of the alkyl group, the
functionalized alkyl group, the alkylene group, the aryl group, the
functionalized aryl group, and the alkyl ether are further
characterized as containing from 1 to about 10 carbon atoms.
[0064] Examples of multifunctional carboxylic acids which can be
employed in the preparation of the coating compositions of the
present invention include, but are not limited to, malic acid,
aconitic acid (cis,trans), itaconic acid, succinic acid, malonic
acid, glutaric acid, adipic acid, pimelic acid, suberic acid,
azelaic acid, sebacic acid, cyclohexyl succinic acid, 1,3,5 benzene
tricarboxylic acid, 1,2,4,5 benzene tetracarboxylic acid,
1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid,
1,1-cyclohexanediacetic acid, 1,3-cyclohexanedicarboxylic acid,
1,1-cyclohexanediacetic acid, 1,3-cycloheanediacetic acid,
1,3,5-cyclohexanetricarboxylic acid and unsaturated dibasic acids
such as fumaric acid and maleic acid and combinations thereof.
[0065] Examples of multifunctional anhydrides which can be used in
the coating compositions of the present invention include, but are
not limited to, the anhydrides of the above mentioned carboxylic
acids such as the cyclic anhydrides of the above mentioned dibasic
acids such as succinic anhydride, itaconic anhydride, glutaric
anhydride, trimellitic anhydride, pyromellitic anhydride, phthalic
anhydride, maleic anhydride, and combinations thereof.
[0066] The multifunctional crosslinker can also include, but is not
limited to, a carboxylic acid or acid anhydride which contains a
--Si(OR') group. An example of such a material is
3-triethoxysilylpropylsuccinic anhydride.
[0067] Optionally, in addition to the multifunctional crosslinker
of the coating composition, a mineral acid such as, for example,
hydrochloric acid or nitric acid, can be used as a co-hydrolysis
catalyst for the hydrolysis of the silane compounds described
herein.
[0068] Any suitable tetrafunctional silane or combination of
tetrafunctional silanes can be used in the present invention in
amounts insufficient to render the coatings rigid. For example, the
tetrafunctional silane can have formulas of Si(OR.sup.9).sub.4,
where R.sup.9 is H, an allyl group containing from 1 to about 5
carbon atoms and ethers thereof, a --Si(OR.sup.10).sub.3 group
where R.sup.10 is a H, an alkyl group containing from 1 to about 5
carbon atoms and ethers thereof, or another --Si(OR.sup.10).sub.3
group and combinations thereof. Examples of tetrafunctional silanes
represented by the formula Si(OR.sup.9).sub.4 are tetramethyl
orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate,
tetraisopropyl orthosilicate, tetrabutyl orthosilicate,
tetraisobutyl orthosilicate, tetrakis(methoxyethoxy)silane,
tetrakis(methoxypropoxy)silane, tetrakis(ethoxyethoxy)silane,
tetrakis(methoxyethoxyethoxy)silane, trimethoxyethoxy-silane,
dimethoxydiethoxysilane, triethoxymethoxysilane,
poly(dimethoxysiloxane), poly(diethoxysiloxane),
poly(dimethoxy-diethoxysiloxane), tetrakis(trimethoxysiloxy)silane,
tetrakis(triethoxysiloxy)silane, and the like. In addition to the
R.sup.9 and R.sup.10 substituents described above for the
tetrafunctional silane, R.sup.9 and R.sup.10 taken with oxygen
(OR.sup.9) and (OR.sup.10) can be carboxylate groups. Examples of
tetrafunctional silanes with carboxylate functionalities are
silicon tetracetate, silicon tetrapropionate and silicon
tetrabutyrate.
[0069] The compositions can include any suitable disilanes in
amounts insufficient to render the coatings rigid. For example, the
disilanes can be represented by the formula
(R.sup.11O).sub.xR.sup.12.sub.3-xSi--R.sup.13.sub.y--Si--R.sup.14.sub.3-x-
(OR.sup.15).sub.x; where x is 0, 1, 2, or 3 and y is 0 or 1;
R.sup.12 and R.sup.14 are either H, an alkyl group containing from
about 1 to about 10 carbon atoms, a functionalized allyl group, an
allylene group, an aryl group, an alkypolyether group, and
combinations thereof; R.sup.11 and R.sup.15 are either H, an allyl
group containing from about 1 to about 10 carbon atoms, an acetyl
group, and combinations thereof. If y is 1 then R.sup.13 can be an
alkylene group containing from about 1 to about 12 carbon atoms, an
alkylenepolyether containing from about 1 to about 12 carbon atoms,
an aryl group, an alkylene substituted aryl group, an alkylene
group which may contain one or more olefins, S, or O. If x is 0
then R.sup.12 and R.sup.14 is Cl or Br. If y is 0 then there is a
direct silicon-silicon bond. Examples of such disilanes include,
but are not limited to, bis(triethoxysilyl)ethane,
bis(triethoxysilyl)methane; bis(trichlorosilyl)methane,
bis(triethoxysilyl)ethylene, 1,3-bis(triethoxysilyl)ethane,
hexaethoxydisiloxane, and hexaethoxydisilane. The selection of the
disilane, as well as the amount of such a disilane incorporated
into the coating compositions, will depend upon the particular
properties to be enhanced or imparted to either the coating
composition or the cured coating composition.
[0070] The compositions can include any other suitable alkyl
silanes (i.e, trifunctional silanes, difunctional silanes,
monofunctional silanes, and mixtures thereof, hereinafter referred
to as silane additives) in amounts insufficient to render the
coatings rigid. The alkyl silane additives which can be
incorporated into the coating compositions of the present invention
can have the formula R.sup.16.sub.xSi(OR.sup.17).sub.4-x where x is
a number of 1, 2 or 3; R.sup.16 is H, or an alkyl group containing
from 1 to about 10 carbon atoms, a functionalized alkyl group, an
alkylene group, an aryl group an alkoxypolyether group, and
combinations thereof; R.sup.17 is H, an alkyl group containing from
1 to about 10 carbon atoms, an acetyl group, and combinations
thereof. Examples of silane additives represented by the
above-defined formula are methyltrimethoxysilane,
ethyltrimethoxysilane, propyltrimethoxysilane,
butyltrimethoxysilane, isobutyltrimethoxysilane,
hexyltrimethoxysilane, octyltrimethoxysilane,
decyltrimethoxysilane, cyclohexyltrimethoxysilane,
cyclohexylmethyltrimethoxysilane,
3-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane,
allyltrimethoxysilane, dimethyldimethoxy-silane,
2-(3-cyclohexenyl)ethyltrimethoxysilane,
3-cyanopropyl-trimethoxysilane, 3-chloropropyltrimethoxysilane,
2-chloroethyltrimethoxysilane, phenethyltrimethoxysilane,
3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane,
phenyltrimethoxysilane, 3-isocyanopropyltrimethoxysilane,
N-(2-aminoethyl)-3-aminopropyltrimethoxysilane,
4-(2-aminoethylaminomethyl)phenethyltrimethoxysilane,
chloromethyltriethoxysilane, 2-chloro-ethyltriethoxysilane,
3-chloropropyltriethoxysilane, phenyltriethoxysilane,
ethyltriethoxysilane, propyltriethoxysilane, butyltriethoxysilane,
isobutyltriethoxysilane, hexyltriethoxysilane,
octyltriethoxysilane, decyltriethoxysilane,
cyclohexyl-triethoxysilane, cyclohexylmethyltriethoxysilane,
3-methacryloxypropyltriethoxysilane, vinyltriethoxysilane,
allyltriethoxysilane, [2-(3-cyclohexenyl)ethyltriethoxysilane,
3-cyanopropyltriethoxysilane,
3-methacrylamidopropyltriethoxysilane,
3-methoxypropyltrimethoxysilane, 3-ethoxypropyltrimethoxysilane,
3-propoxypropyltrimethoxysilane, 3-methoxyethyltrimethoxysilane,
3-ethoxyethyltrimethoxysilane, 3-propoxyethyltrimethoxysilane. The
selection of the silane additive, as well as the amount of such
silane additive incorporated into the coating compositions, will
depend upon the particular properties to be enhanced or imparted to
either the coating composition or the cured coating
composition.
[0071] In certain applications, it can be useful to add colloidal
silica to the coating composition in amounts insufficient to render
the cured coating rigid. Colloidal silica is commercially available
under a number of different tradename designations, including Nalco
(Nalco Chemical Co., Naperville, Ill.); Nyacol (Nyacol Products,
Inc., Ashland, Mass.); Snowtex (Nissan Chemical Industries, LTD.,
Tokyo, Japan); Ludok (DuPont Company, Wilmington, Del.); and
Highlink OG (Clariant, Charlotte, N.C.). The colloidal silica is an
aqueous or organic solvent dispersion of particulate silica and the
various products differ principally by particle size, silica
concentration, pH, presence of stabilizing ions, solvent makeup,
and the like. It is understood by those skilled in the art that
substantially different product properties can be obtained through
the selection of different colloidal silicas.
[0072] Colloidal silica, when added to a coating composition, is
considered a reactive material. The surface of the silica is
covered with silicon bound hydroxyls, some of which are
deprotonated, which can interact with materials in the coating
composition. The extent of these interactions is dictated by a
variety of factors, including solvent system, pH, concentration,
and ionic strength. The manufacturing process further affects these
interactions. Those skilled in the art recognize that colloidal
silica can be added into a coating formulation in different ways
with different results. The colloidal silica can be added to the
coating composition at any suitable time.
[0073] The addition of colloidal silica to the coating compositions
of the present invention can further enhance the abrasion
resistance of the cured coating compositions and can further
contribute to the overall stability of the coating compositions. In
the same manner, other metal oxides may be added to the coating
compositions of the present invention. Such additions may be made
instead of, or in addition to, any colloidal silica additions.
Metal oxides may be added to the inventive coatings to provide or
enhance specific properties of the cured coating, such as abrasion
resistance, refractive index, anti-static, anti-reflectance,
weatherability, etc. Those skilled in the art recognize that the
same types of reasons for including the colloidal silica in the
compositions of the present invention also apply more generally to
including metal oxides. Examples of metal oxides that may be used
in the coating compositions of the present invention include
silica, zirconia, titania, ceria, tin oxide, and combinations
thereof.
[0074] The amount of colloidal silica incorporated into the coating
compositions of the present invention can vary widely and will
generally depend on the desired properties of the cured coating
produced from the coating compositions, as well as the desired
stability of the coating compositions. Similarly, the amount of
metal oxides incorporated into the coating compositions of the
present invention can vary widely and will generally depend on the
desired properties of the cured coating produced from the coating
compositions, as well as the desired stability of the coating
compositions. The colloidal silica and/or metal oxides will
generally have a particle size in the range of 2 to 150
millimicrons in diameter, and more desirably, a particle size in
the range of from about 2 to 50 millimicrons.
[0075] Although a catalyst is not an essential ingredient of the
present invention, the addition of a catalyst can affect abrasion
resistance and other properties of the coating, including
stability, porosity, cosmetics, caustic resistance, water
resistance, etc. The amount of catalyst used can vary widely, but
when present will generally be in an amount sufficient to provide
from about 0.1 to about 10 weight percent, based on the total
solids of the coating composition.
[0076] Examples of catalysts that can be incorporated into the
coating compositions of the present invention include, but are not
limited to, (i) metal acetylacetonates, (ii) diamides, (iii)
imidazoles, (iv) amines and ammonium salts, (v) organic sulfonic
acids and their amine salts, (vi) alkali metal salts of carboxylic
acids, (vii) alkali metal hydroxides and (viii) fluoride salts.
Thus, examples of such catalysts include for group (i) such
compounds as aluminum, zinc, iron and cobalt acetylacetonates; for
group (ii) dicyandiamide; for group (iii) such compounds as
2-methylimidazole, 2-ethyl-4-methylimidazole and
1-cyanoethyl-2-propylimidazole; for group (iv) such compounds as
benzyldimethylamine, and 1,2-diaminocyclohexane; for group (v) such
compounds as trifluoromethanesulfonic acid; for group (vi) such
compounds as sodium acetate; for group (vii) such compounds as
sodium hydroxide, and potassium hydroxide; and for group (viii)
such compounds as tetra n-butyl ammonium fluoride, and the
like.
[0077] An effective amount of a leveling or flow control agent can
be incorporated into the composition to spread more evenly or level
the composition on the surface of the substrate and to provide
substantially uniform contact with the substrate. The amount of the
leveling or flow control agent can vary widely, but can be an
amount sufficient to provide the coating composition with from
about 10 to about 5,000 ppm of the leveling or flow control agent.
Any conventional, commercially available leveling or flow control
agent which is compatible with the coating composition and the
substrate, which is capable of leveling the coating composition on
a substrate, and which enhances wetting between the coating
composition and the substrate can be employed. The use of leveling
and flow control agents is well known in the art and has been
described in the "Handbook of Coating Additives" (ed. Leonard J.
Calbo, pub. Marcel Dekker), pg 119-145, the entire contents of
which are hereby expressly incorporated herein by reference in
their entirety.
[0078] Examples of such leveling or flow control agents which can
be incorporated into the coating compositions of the present
invention include, but are not limited to, organic polyethers such
as TRITON X-100, X-405, and N-57 from Rohm and Haas, silicones such
as Paint Additive 3, Paint Additive 29, and Paint Additive 57 from
Dow Corning, SILWET L-77 and SILWET L-7600 from OSi Specialties,
and fluorosurfactants such as FLUORAD FC-4430 from 3M
Corporation.
[0079] In addition, other additives can be added to the coating
compositions of the present invention to enhance the usefulness of
the coating compositions or the coatings produced by curing the
coating compositions. For example, ultraviolet absorbers,
antioxidants, and the like can be incorporated into the coating
compositions of the present invention if desired.
[0080] In one embodiment, ultraviolet stabilizers can be added to
the coating compositions. Any suitable ultraviolet stabilizer and
radical scavenger may be used in the present invention at any
concentration effective to protect a substrate from the degradative
effects of light. The use of these additives is described in the
"handbook of Coating Additives" (ed. Leonard J. Calbo, pub. Marcel
Dekker), pg 225-269. In another embodiment, ultraviolet stabilizers
can be added to the primer compositions.
[0081] In another embodiment, a surfactant or mix of surfactants
can be included in the coating compositions to provide the coated
article with anti-fogging properties. Including surfactant results
in a high wetting tension on the surface of the dried coating, and
the high wetting tension prevents the formation of minute droplets,
i.e., fog, on the coating surface. The surfactant further enhances
the wet-out of the water to maintain a clear, non-fogged surface.
An example of a suitable surfactant is Dioctylsulfosuccinate,
available as Aerosol OT 75 from Cytec Industries Inc. West
Patterson, N.J. The surfactant component can be present at about
0.4 to 15% weight percent of the coating composition. Higher levels
can be used; however, they can result in an increase in haze, which
can be undesirable for many applications. The anti-fogging effect
of coatings can be measured by storing the article with the cured
coating on the surface at 20.degree. C., and then subjecting the
coated article to saturated water vapor at 60.degree. C. If the
coated article becomes clear after 10 seconds and remains clear for
at least 1 minute, the coating is anti-fogging.
[0082] The coating compositions can be made in any suitable manner.
For example, the at least one of the epoxy functional silane and
the diol functional organopolysiloxane and the multifunctional
crosslinker can be added to a solvent and water and allowed to
react at room temperature overnight. Additional additives, such as
a leveling agent, may then be added. The coating composition can be
applied to a substrate and cured to form a coating.
[0083] In accordance with embodiments of the present invention, an
article can be provided. The article can comprise a substrate and a
coating formed on at least one surface of the substrate by curing
coating compositions of the present invention. Any suitable
substrate may be coated with the coating compositions of the
present invention. For example, plastic materials, wood, metal,
printed surfaces, and leather can be coated. The compositions are
especially useful as coatings for synthetic organic polymeric
substrates in sheet or film form, such as acrylic polymers,
poly(ethyleneterephthalate), polycarbonates, polyamides,
polyimides, copolymers of acrylonitrile-styrene,
styrene-acrylonitrile-butadiene copolymers, polyvinyl chloride,
butyrates, and the like. Transparent polymeric materials coated
with these compositions are useful as flat or curved enclosures,
such as windows, skylights and windshields, especially for
transportation equipment. Plastic lenses, such as acrylic,
poly(diethylene glycol-bis-allyl carbonate) (ADC) or polycarbonate
lenses, can also be coated with the compositions of the
invention.
[0084] The coating compositions can be coated on the substrates in
any suitable manner. For example, the compositions of the invention
can be applied to solid substrates by conventional methods, such as
flow coating, spray coating, curtain coating, dip coating, spin
coating, roll coating, etc. to form a continuous surface film.
[0085] By choice of proper coating composition, application
conditions and pretreatment (including the use of primers) of the
substrate, the coating compositions of the present invention can be
adhered to substantially all solid surfaces. After application of
the coating compositions of the present invention to solid
substrates, the coatings can be heat cured at any suitable
temperature for any suitable period of time. For example, the
coatings can be heat cured at temperatures in the range of 50 to
200.degree. C. or more for a period of from seconds to 18 hours or
more. It will be understood that the coatings can be cured in any
other suitable manner. For example, an ultraviolet activated
photoinitiator capable of initiating cationic cure can be added so
the coating can be at least partially cured by ultraviolet light.
It will be understood that the coatings can be subsequently cured
by another process such as a heat cure. Any suitable photoinitiator
can be used. For example, aromatic onium salt or iron arene salt
complexes available from Ciba Specialty Chemicals Corp., Terrytown,
N.Y. can be used.
[0086] The coating thickness can be varied by means of the
particular application technique, but coatings having a thickness
of from about 0.5 to 20 microns or from about 1 to about 10 microns
can be used. It will be understood that the coatings can be
substantially transparent.
[0087] In accordance with one embodiment of the present invention,
the coating compositions may be applied to a substrate having a
primer disposed thereon. Any suitable primer can be used. For
example, a polyurethane dispersion based primer can be used.
Examples of such suitable primers are detailed in U.S. Pat. No.
5,316,791, the entire contents of which is incorporated herein
expressly by reference. An example of a such a suitable primer is
PR1180 available from SDC Technologies, Inc., Anaheim, Calif. In
another example, the primer can be modified with ultraviolet light
absorbing substances and/or radical scavengers in order to increase
the weatherability of the coated substrate. The primer can be
applied to a substrate and air or thermally dried, e.g., air-dried
for less than about 2 hours, and the coating composition can be
subsequently applied and cured, after which the coated substrate
may be formed.
[0088] In accordance with further embodiments of the present
invention, formed articles are provided. The formed articles
comprise a formed substrate having a coating in accordance with the
present invention on at least one surface. The coating is applied
to the formed articles prior to forming the article.
EXAMPLES
[0089] The following examples are for purposes of illustration only
and are not intended to limit the scope of the claims which are
appended hereto. All references cited herein are specifically
incorporated by reference.
Example 1
Preparation of a Diol Functional Organopolysiloxane
[0090] 1000g of 3-glycidoxypropyltrimethoxysilane epoxy functional
silane (A-187, Witco Corporation, Greenwich, Conn.) was added to a
5 liter glass flask fitted with a distillation apparatus. A mixture
of 40 g HCl (0.05 N) and 2960 g of deionized water were then added
to the 5 liter flask. The solution was then heated to reflux. After
3 hours of reflux, 743 g of solvent was removed by distillation.
The product was used "as-is" without farther purification.
Example 2
Coating Composition and Primer
[0091] 7.5 grams of deionized (DI) water were added dropwise to a
stirring solution of 15.0 grams of A-187, 19.3 grams of
dihydro-3-(3-(triethoxysilyl)propyl)-2,5-furandione silylated
multifunctional anyhdride (GF20, Wacker chemical corporation,
Adrian, Mich.), and 140.0 grams of isopropanol solvent. The mixture
was stirred at room temperature overnight. 0.18 grams of a solution
of leveling agent PA-57 (Dow Corning corporation, Midland, Mich.),
10 weight percent propylene glycol monomethyl ether (PM ether,
Ashland Chemical, Columbus, Ohio) were added. The composition was
left to stir for an additional 20 minutes after the addition of the
PA-57 to insure mixing.
[0092] This coating composition was applied by flow coating to a
PR-1180 (SDC Technologies, Inc., Anaheim, Calif.) primed 1/4''
thick polycarbonate plaque. After air-drying for 30 minutes, the
coating was cured for 2 hours at 130.degree. C. The haze gain
results from a Taber test using CS-10F wheels in accordance with
the procedure outlined herein were: 1.7% haze at 50 revolutions and
7.5% haze after 200 revolutions. The thickness of the topcoat was
3.5 microns. The formability of the coating was evaluated as
described herein on a cylindrical mandrel and no crack was observed
at 5'' radius.
Example 3
Coating Composition and Primer
[0093] 8.0 grams of DI water were added dropwise to a stirring
solution of 17.7 grams of A-187, 15.2 grams of GF20, and 140.0
grams of isopropanol. The mixture was stirred at room temperature
overnight. 0.18 grams of a solution of PA-57, 10 weight percent in
PM glycol ether, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing.
[0094] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 2.3%
haze at 50 revolutions and 11.4% haze after 200 revolutions.
Thickness of the topcoat was 3.5 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 4'' radius.
Example 4
Coating Composition and Primer
[0095] 17.0 grams of DI water were added dropwise to a stirring
solution of 45.0 grams of A-187, 29.0 grains of GF20, and 280.0
grams of isopropanol. The mixture was stirred at room temperature
overnight. 0.37 grams of a solution of PA-57, 10 weight percent in
PM glycol ether, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing.
[0096] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 3.1%
haze at 50 revolutions and 17.2% haze after 200 revolutions.
Thickness of the topcoat was 3.2 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 5
Coating Composition and Primer
[0097] 16.0 grams of DI water were added dropwise to a stirring
solution of 47.0 grams of A-187, 20.0 grams of GF20, and 280.0
grams of isopropanol. The mixture was stirred at room temperature
overnight. 0.36 grams of a solution of PA-57, 10 weight percent in
PM glycol ether, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing.
[0098] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 5.3%
haze at 50 revolutions and 38.1% haze after 200 revolutions.
Thickness of the topcoat was 3.1 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 6
Coating Composition and Primer
[0099] 15.0 grams of DI water were added dropwise to a stirring
solution of 47.0 grams of A-187, 15.0 grams of GF20, and 260.0
grams of isopropanol. The mixture was stirred at room temperature
overnight. 0.34 grams of a solution of PA-57, 10 weight percent in
PM glycol ether, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing.
[0100] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 6.0%
haze at 50 revolutions and 59.1% haze after 200 revolutions.
Thickness of the topcoat was 3.2 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 7
Coating Composition and Primer
[0101] 14.3 grams of DI water were added dropwise to a stirring
solution of 30.0 grams of A-187, 38.6 grams of GF20, and 300.0
grams of PM glycol ether (PMOH) solvent. The mixture was stirred at
room temperature for three days. 0.38 grams of a solution of PA-57,
10 weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0102] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 3.0%
haze at 50 revolutions and 14.0% haze after 200 revolutions.
Thickness of the topcoat was 3.0 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 8
Coating Composition and Primer
[0103] 16.2 grams of DI water were added dropwise to a stirring
solution of 45.0 grams of A-187, 29.0 grams of GF20, and 300.0
grams of PM glycol ether (PMOH). The mixture was stirred at room
temperature for three days. 0.39 grams of a solution of PA-57, 10
weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0104] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 4.7%
haze at 50 revolutions and 26.7% haze after 200 revolutions.
Thickness of the topcoat was 3.0 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 9
Coating Composition and Primer
[0105] 15.8 grams of DI water were added dropwise to a stirring
solution of 47.2 grams of A-187, 20.3 grams of GF20, and 300.0
grams of PM glycol ether (PMOH). The mixture was stirred at room
temperature for three days. 0.38 grams of a solution of PA-57, 10
weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0106] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 5.8%
haze at 50 revolutions and 34.5% haze after 200 revolutions.
Thickness of the topcoat was 3.0 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 10
Coating Composition and Primer
[0107] 15.0 grams of DI water were added dropwise to a stirring
solution of 47.2 grains of A-187, 15.2 grams of GF20, and 265.0
grams of PM glycol ether (PMOH). The mixture was stirred at room
temperature for three days. 0.34 grams of a solution of PA-57, 10
weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0108] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 6.4%
haze at 50 revolutions and 57.2% haze after 200 revolutions.
Thickness of the topcoat was 3.0 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
Example 11
Coating Composition and Primer
[0109] 2.7 grams of DI water were added dropwise to a stirring
solution of 3.8 grams of A-187, 9.7 grams of GF20, and 55 grams of
isopropanol/PM glycol ether (1:1). The mixture was stirred at room
temperature for three days. 0.08 grams of a solution of PA-57, 10
weight percent in PM glycol ether, were added. The composition was
left to stir for an additional 20 minutes after the addition of the
PA-57 to insure mixing.
[0110] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 1.6%
haze at 50 revolutions and 5.6% haze after 200 revolutions.
Thickness of the topcoat was 3.2 microns. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 6'' radius.
Example 12
Coating Composition and Primer
[0111] 4.0 grams of DI water were added dropwise to a stirring
suspension of 15.0 grams of A-187, 1.8 grams of itaconic acid
crosslinker, and 75.0 grams of isopropanol. The mixture was stirred
at room temperature overnight. 0.10 grams of a solution of PA-57,
10 weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0112] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 13.3%
haze at 50 revolutions and 67.2% haze after 200 revolutions.
Formability of the coating was evaluated on a cylindrical mandrel
and no crack was observed at 3'' radius.
Example 13
Coating Composition and Primer
[0113] 4.0 grams of DI water were added dropwise to a stirring
suspension of 15.0 grams of A-187, 1.4 grams of succinic anhydride
crosslinker, and 70.0 grams of isopropanol. The mixture was stirred
at room temperature overnight. 0.10 grams of a solution of PA-57,
10 weight percent in PMOH, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing.
[0114] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 36.2%
haze at 50 revolutions. Formability of the coating was evaluated on
a cylindrical mandrel and no crack was observed at 3'' radius.
Example 14
Coating Composition and Primer
[0115] 4.0 grams of DI water were added dropwise to a stirring
suspension of 15.0 grams of A-187, 1.4 grams of succinic anhydride,
and 70.0 grams of PM glycol ether (PMOH). The mixture was stirred
at room temperature for three days. 0.10 grams of a solution of
PA-57, 10 weight percent in PMOH, were added. The composition was
left to stir for an additional 20 minutes after the addition of the
PA-57 to insure mixing.
[0116] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 42.0%
haze at 50 revolutions. Formability of the coating was evaluated on
a cylindrical mandrel and no crack was observed at 3'' radius.
Example 15
Coating Composition and Primer
[0117] A mixture of 15.0 grams of
trimethoxy(3-oxiranylmethoxy)propylsilane hydrolyzed aqueous
solution available as HS2926 (SIVENTO Inc, Piscataway, N.J.), 9.66
grams of GF20, and 70.0 grams of isopropanol was stirred at room
temperature overnight. 0.10 grams of a solution of PA-57, 10 weight
percent in PM glycol ether, were added. The composition was left to
stir for an additional 20 minutes after the addition of the PA-57
to insure mixing. This coating composition was applied by flow
coating to a PR-1180 primed 1/4'' thick polycarbonate plaque. After
air-drying for 30 minutes, the coating was cured for 2 hours at
130.degree. C. Haze gain results from a Taber test using CS-10F
wheels were: 1.0% haze at 50 revolutions and 3.0% haze after 200
revolutions. Thickness of the topcoat was 3.0 microns. Formability
of the coating was evaluated on a cylindrical mandrel and no crack
was observed at 7'' radius.
Example 16
Coating Composition and Primer
[0118] A mixture of 15.0 grams of HS2926, 9.66 grams of GF20, and
70.0 grains of PM glycol ether was stirred at room temperature
overnight. 0.10 grams of a solution of PA-57, 10 weight percent in
PM glycol ether, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing. This composition was aged at room temperature for 5 days
before a coating application. The coating composition was applied
by flow coating to a PR-1180 primed 1/4'' thick polycarbonate
plaque. After air-drying for 30 minutes, the coating was cured for
2 hours at 130.degree. C. Haze gain results from a Taber test using
CS-10F wheels were: 1.34% haze at 50 revolutions and 4.19% haze
after 200 revolutions. Thickness of the topcoat was 3.0 microns.
Formability of the coating was evaluated on a cylindrical mandrel
and no crack was observed at 7'' radius.
Example 17
Coating Composition and Primer
[0119] A mixture of 15.0 grains of HS2926, 0.7 grams of succinic
anhydride, and 30.0 grams of isopropanol was stirred at room
temperature overnight. 0.05 grams of a solution of PA-57, 10 weight
percent in PMOH, were added. The composition was left to stir for
an additional 20 minutes after the addition of the PA-57 to insure
mixing. This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Haze gain results from a Taber test using CS-10F wheels were: 26.0%
haze at 25 revolutions. Formability of the coating was evaluated on
a cylindrical mandrel and no crack was observed at 3'' radius.
Example 18
Comparative Example Coating Composition and Primer
[0120] A commercially available SDC MP1154D (SDC Technologies,
Inc., Anaheim, Calif.), a representative of coatings described in
U.S. Pat. No. 6,001,163, was applied by flow coating to a PR-1180
primed 1/4'' thick polycarbonate plaque. After air-drying for 30
minutes, the coating was cured for 2 hours at 130.degree. C. Haze
gain results from a Taber test using CS-10F wheels were: 0.39% haze
at 50 revolutions and 0.78% haze after 200 revolutions. Thickness
of the topcoat was 3.0 microns. The coated sample was placed in an
oven in accordance with the thermoforming procedure outlined
herein. At 165.degree. C., the coating cracked before it could be
placed on a cylindrical mandrel.
Example 19
Comparative Example Coating Composition and Primer
[0121] A commercially available SDC MP1193A1 (SDC Technologies,
Inc., Anaheim, Calif.), a representative of coatings described in
U.S. Pat. No. 6,348,269, was applied by flow coating to a PR-1180
primed 1/4'' thick polycarbonate plaque. After air-drying for 30
minutes, the coating was cured for 2 hours at 130.degree. C. Haze
gain results from a Taber test using CS-10F wheels were: 0.22% haze
at 50 revolutions and 0.47% haze after 200 revolutions. Thickness
of the topcoat was 5.0 microns. The coated sample was placed in an
oven in accordance with the thermoforming procedure outlined
herein. At 165.degree. C., the coating cracked before it could be
placed on a cylindrical mandrel.
Example 20
Comparative Example Coating Composition and Primer
[0122] A commercially available SDC TC332 (SDC Technologies, Inc.,
Anaheim, Calif.), a representative of coatings described in U.S.
Pat. No. 5,013,608 was applied by flow coating to a PR-1180 primed
1/4'' thick polycarbonate plaque. After air-drying for 30 minutes,
the coating was cured for 2 hours at 130.degree. C. Haze gain
results from a Taber test using CS-10F wheels were: 1.48% haze at
50 revolutions and 3.57% haze after 200 revolutions. Thickness of
the topcoat was 3.5 microns. The coated sample was placed in an
oven in accordance with the thermoforming procedure outlined
herein. At 165.degree. C., the coating cracked before it could be
placed on a cylindrical mandrel.
Example 21
Anti-fog Coating Composition and Primer
[0123] 1.91 grams of DI water were added dropwise to a stirring
solution of 4.0 grams of A-187, 5.15 grams of GF20, and 40 grams of
PM glycol ether. The mixture was stirred at room temperature
overnight. 0.74 grams of surfactant sodium dioctyl sulfosuccinate
in mixture of ethanol and water (OT-75) Van Waters & Rogers
Inc., Kirkland, Wash.) (75% solid) was added. The composition was
left to stir for two hours at room temperature and then aged at a
100 F warm room for 3 weeks before coating application.
[0124] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Coating on the surface was stored at 20.degree. C. and than
subjected the coated article to saturated water vapor at 60.degree.
C. The coated article became clear after 10 seconds and remained
clear for at least one minute. Haze gain results from a Taber test
using CS-10F wheels were: 1.6% haze at 50 revolutions and 9.0% haze
after 200 revolutions. Thickness of the topcoat was 3.2 microns.
Formability of the coating was evaluated on a cylindrical mandrel
and no crack was observed at 4'' radius.
Example 22
Anti-fog Coating Composition and Primer
[0125] 2.11 grams of DI water were added dropwise to a stirring
solution of 5.88 grams of A-187, 3.79 grams of GF20, and 39.2 grams
of PM glycol ether. The mixture was stirred at room temperature
overnight. 0.74 grams of OT-75 (75% solid) was added. The
composition was left to stir for two hours at room temperature and
then aged at a 100.degree. F. for 3 weeks before coating
application.
[0126] This coating composition was applied by flow coating to a
PR-1180 primed 1/4'' thick polycarbonate plaque. After air-drying
for 30 minutes, the coating was cured for 2 hours at 130.degree. C.
Coating on the surface was stored at 20.degree. C. and than
subjected the coated article to saturated water vapor at 60.degree.
C. The coated article became clear after 10 seconds and remained
clear for at least one minute. Haze gain results from a Taber test
using CS-10F wheels were: 4.8% haze at 50 revolutions and 33% haze
after 200 revolutions. Thickness of the topcoat was 3.2 microns.
Formability of the coating was evaluated on a cylindrical mandrel
and no crack was observed at 4'' radius.
Example 23
Comparative Example Anti-fog Coating Composition and Primer
[0127] A commercially available SDC AF1140 (SDC Technologies, Inc.,
Anaheim, Calif.) was applied by flow coating to a PR-1180 primed
1/4'' thick polycarbonate plaque. After air-drying for 30 minutes,
the coating was cured for 2 hours at 130.degree. C. The coating on
the surface was stored at 20.degree. C. and than subjected to
saturated water vapor at 60.degree. C. The coated article became
clear after 10 seconds and remained clear for at least 1 minute.
Haze gain results from a Taber test using CS-10F wheels were: 3.20%
haze at 50 revolutions and 14.3% haze after 200 revolutions.
Thickness of the topcoat was 3.1 microns. Formability of the
coating was evaluated on a cylindrical mandrel and crack was
observed at less than a 10'' radius.
Example 24
Coating and Weatherable Primer
[0128] A weatherable primer was prepared by mixing a
Poly(oxy-1,2-ethanediyl),
.alpha.-[3-[3-(2H-benzotriazo(-2-yl)-5-(1,1-dimethylethyl)-4-hydroxypheny-
l)-1-oxopropyl]-.omega.-[3-[3
[(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropo-
xy], 30-45% by wt. and Poly(oxy-1,2-ethanediyl),
.alpha.-[3-[3-(2H-benzotriazo(-2-yl)-5-(1,1-dimethylethyl)-4-hydroxypheny-
l)-1-oxopropyl]-.omega.-hydroxy-, 40-55% by wt. (Tinuvin 1130, Ciba
Specialty Chemicals Corporation, Tarrytown, N.Y.) into a
commercially available PR1180 primer. Thus, 6.42 grams of
Tinuvin1130 was added to 150 grams of PR1180. The resulting
composition was left to stir for four hours before coating
application.
[0129] This composition was applied as a primer by flow coating to
a 1/4'' thick polycarbonate plaque. The printer was air dried for
one hour before application of a topcoat of Example 7. The final
coating was cured for 2 hours at 130.degree. C. Haze gain results
from a Taber test using CS-10F wheels were: 2.0% haze at 50
revolutions and 11% haze after 200 revolutions. Formability of the
coating was evaluated on a cylindrical mandrel and no crack was
observed at 3'' radius.
[0130] The weatherability of the coating was evaluated by both QUV
and Weather-O-Meter. The coating doesn't show adhesion failure and
crack after 200 hours exposure to ultraviolet light in both
accelerated weathering testers. The QUV was operated under the
condition of 8 hours UV cycle at 70.degree. C. and 4 hours
condensation cycle at 50.degree. C. The Weather-O-Meter was
operated according to ASTM 155-1.
Example 25
Coating and Weatherable Primer
[0131] 3.0 grams of Tinuvin1130 was added to 150 grams of PR1180.
The resulting composition was left to stir for four hours before
coating application. This composition was applied as a primer by
flow coating to a 1/4'' thick polycarbonate plaque. The primer was
air dried for one hour before an application of a topcoat of
example 7. The final coating was cured for 2 hours at 130.degree.
C.
[0132] Haze gain results from a Taber test using CS-10F wheels
were: 2.7% haze at 50 revolutions and 12% haze after 200
revolutions. Formability of the coating was evaluated on a
cylindrical mandrel and no crack was observed at 3'' radius.
[0133] The weatherability of the coating was evaluated by both QUV
and Weather-O-Meter. The coating doesn't show adhesion failure and
crack until after 200 hours exposure to ultraviolet light in both
accelerated weathering testers. The QUV was operated under the
condition of 8 hours UV cycle at 70.degree. C. and 4 hours
condensation cycle at 50.degree. C. The Weather-O-Meter was
operated according to ASTM 155-1.
[0134] It will be understood that various changes may be made
without departing from the scope of the invention, which is not to
be considered limited to what is described in the description.
* * * * *