U.S. patent application number 12/338489 was filed with the patent office on 2009-06-25 for binders containing nanoparticles.
This patent application is currently assigned to Bayer MaterialScience AG. Invention is credited to Michael Mager, Markus Mechtel, Alice Muenzmay, Thomas Muenzmay, Nusret Yuva.
Application Number | 20090163618 12/338489 |
Document ID | / |
Family ID | 40521955 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090163618 |
Kind Code |
A1 |
Muenzmay; Thomas ; et
al. |
June 25, 2009 |
BINDERS CONTAINING NANOPARTICLES
Abstract
The present invention relates to aqueous binder dispersions
based on silane-modified polymeric binders and inorganic
nanoparticles, a process for the preparation thereof and the use
thereof for the production of high quality coatings, in particular
clear lacquers.
Inventors: |
Muenzmay; Thomas; (Dormagen,
DE) ; Muenzmay; Alice; (Dormagen, DE) ; Mager;
Michael; (Leverkusen, DE) ; Mechtel; Markus;
(Bergisch Gladbach, DE) ; Yuva; Nusret;
(Burscheid, DE) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Assignee: |
Bayer MaterialScience AG
Leverkusen
DE
|
Family ID: |
40521955 |
Appl. No.: |
12/338489 |
Filed: |
December 18, 2008 |
Current U.S.
Class: |
523/209 |
Current CPC
Class: |
C08G 18/706 20130101;
C09D 7/62 20180101; C08F 220/20 20130101; C09D 5/028 20130101; C09D
133/06 20130101; C08G 18/6295 20130101; C08K 3/36 20130101; C08K
9/04 20130101; C09D 175/04 20130101; C08G 18/6254 20130101; C08K
3/013 20180101; C09D 175/04 20130101; C08L 2666/54 20130101; C08F
220/20 20130101; C08F 220/1811 20200201; C08F 212/08 20130101; C08F
220/1804 20200201; C08F 220/1808 20200201; C08F 230/08 20130101;
C08K 3/013 20180101; C08L 101/10 20130101; C08K 9/04 20130101; C08L
101/10 20130101; C08F 220/20 20130101; C08F 220/1811 20200201; C08F
212/08 20130101; C08F 220/1804 20200201; C08F 220/1808 20200201;
C08F 230/08 20130101 |
Class at
Publication: |
523/209 |
International
Class: |
C08K 9/10 20060101
C08K009/10 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 19, 2007 |
DE |
102007061876.1 |
Claims
1. An aqueous formulation comprising B) a silane-modified
copolymer; B) optionally surface-modified inorganic particles
having an average particle size (z-mean), as determined by means of
dynamic light scattering in dispersion, of less than 200 nm; and C)
water.
2. The aqueous formulation of claim 1, wherein said silane-modified
copolymer A) comprises groups of general formula (1)
--Si(R.sup.1O).sub.2R.sup.2 (1) wherein R.sup.1 is a C.sub.2- to
C.sub.8-alkyl radical; and R.sup.2 is (R.sup.1O) or a C.sub.1- to
C.sub.5-alkyl radical.
3. The aqueous formulation of claim 1, wherein said silane-modified
copolymer A) is a copolymer which is built up from I) a
hydroxy-functional hydrophobic polymer containing as builder
monomers Ia) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; Ib) hydroxy-functional
monomers; and IS1) silane-functional monomers capable of
polymerization; and II) a hydroxy-functional hydrophilic polymer
containing as builder components IIa) (meth)acrylic acid esters
having C.sub.1- to C.sub.18-hydrocarbon radicals in the alcohol
part and/or vinylaromatics and/or vinyl esters; IIb)
hydroxy-functional monomers; and IIc) acid-functional monomers.
4. The aqueous formulation of claim 1, wherein said silane-modified
copolymer A) is a copolymer which is built up from I) a
hydroxy-functional hydrophobic polymer containing as builder
monomers Ia) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; and Ib) hydroxy-functional
monomers; and II) a hydroxy-functional hydrophilic polymer
containing as builder components IIa) (meth)acrylic acid esters
having C.sub.1- to C.sub.18-hydrocarbon radicals in the alcohol
part and/or vinylaromatics and/or vinyl esters; IIb)
hydroxy-functional monomers; IIe) acid-functional monomers; and
IIS1) silane-functional monomers capable of polymerization.
5. The aqueous formulation of claim 3, wherein said
silane-functional monomer IS1), which is capable of polymerization,
is a compound of the general formula (2)
(R.sup.1O).sub.2R.sup.2Si--(CH.dbd.CH.sub.2) (2) wherein R.sup.1 is
a C.sub.2- to C.sub.8-alkyl radical; and R.sup.2 is (R.sup.1O) or a
C.sub.1- to C.sub.5-alkyl radical; and/or a compound of the general
formula (3)
(R.sup.1O).sub.2R.sup.2Si(CH.sub.2).sub.m--O(CO)--(CR.sup.3.dbd.CH.sub.2)
(3) wherein R.sup.1 is a C.sub.2- to C.sub.8-alkyl radical; R.sup.2
is (R.sup.1O) or a C.sub.1- to C.sub.5-alkyl radical; R.sup.3 is H
or CH.sub.3; and m is 1 to 4.
6. The aqueous formulation of claim 4, wherein said
silane-functional monomer IIS1), which is capable of
polymerization, is a compound of the general formula (2)
(R.sup.1O).sub.2R.sup.2Si--(CH.dbd.CH.sub.2) (2) wherein R.sup.1 is
a C.sub.2- to C.sub.8-alkyl radical; and R.sup.2 is (R.sup.1O)) or
a C.sub.3- to C.sub.5-alkyl radical; and/or a compound of the
general formula (3)
(R.sup.1O).sub.2R.sup.2Si(CH.sub.2).sub.m--O(CO)--(CR.sup.3.dbd.CH.sub.2)
(3) wherein R.sup.1 is a C.sub.2- to C.sub.8-alkyl radical; R.sup.2
is (R.sup.1O) or a C.sub.1- to C.sub.5-alkyl radical; R.sup.3 is H
or CH.sub.3; and m is 1 to 4.
7. The aqueous formulation of claim 3, wherein said
silane-functional monomer IS1), which are capable of
polymerization, is selected from the group consisting of
vinyltriethoxysilane, vinyltrisisopropoxysilane,
vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane,
vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane,
3-(triethoxysilyl)-propyl methacrylate or
3-(tris-isopropoxysilyl)-propyl methacrylate,
vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane, and
vinyltri-t-butoxysilane.
8. The aqueous formulation of claim 4, wherein said
silane-functional monomers IIS1), which are capable of
polymerization, is selected from the group consisting of
vinyltriethoxysilane, vinyltrisisopropoxysilane,
vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane,
vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane,
3-(triethoxysilyl)-propyl methacrylate or
3-(tris-isopropoxysilyl)-propyl methacrylate,
vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane, and
vinyltri-t-butoxysilane.
9. The aqueous formulation of claim 1, wherein said silane
functional copolymer A) is a copolymer which is built up from I) a
hydroxy-functional hydrophobic polymer containing as builder
monomers Ia) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; Ib) hydroxy-functional
monomers; and II) a hydroxy-functional hydrophilic polymer
containing as builder components IIa) (meth)acrylic acid esters
having C.sub.1- to C.sub.18-hydrocarbon radicals in the alcohol
part and/or vinylaromatics and/or vinyl esters; IIb)
hydroxy-functional monomers; IIc) acid-functional monomers; and
IIS2) monomers which contain at least one epoxide function in
addition to silane groups.
10. The aqueous formulation of claim 9, wherein said monomers IIS2)
are selected from the group consisting of
.gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyl-tris-isopropoxysilane,
.gamma.-glycidoxypropyl-diethoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-triethoxysilane, and
.beta.-(3,4-epoxycyclohexyl)-tris-isopropoxysilane.
11. The aqueous formulation of claim 1, wherein said inorganic
particles B) are selected from the group consisting of inorganic
oxides, mixed oxides, carbides, borides, and nitrides of elements
of main group II to IV and/or elements of subgroup I to VIII of the
periodic table, including the lanthanides.
12. The aqueous formulation of claim 1, wherein said inorganic
particles B) are inorganic nanoparticles in a colloidally disperse
form in organic solvents or in water.
13. The aqueous formulation of claim 1, wherein said inorganic
particles B) are inorganic particles in the form of aqueous
formulations.
14. The aqueous formulation of claim 1, wherein said inorganic
particles B) are surface-modified inorganic nanoparticles.
15. An aqueous coating composition comprising the aqueous
formulation of claim 1 and at least one crosslinking agent D).
16. An aqueous two-component coating composition comprising the
aqueous formulation of claim 1 and a polyisocyanate.
17. A clear lacquer comprising the aqueous formulation of claim 1.
Description
RELATED APPLICATIONS
[0001] This application claims benefit to German Patent Application
No. 10 2007 061 876.1, filed Dec. 19, 2007, which is incorporated
herein by reference in its entirety for all useful purposes.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to aqueous binder dispersions
based on silane-modified polymeric binders and inorganic
nanoparticles, a process for the preparation thereof and the use
thereof for the preparation of high quality coatings, in particular
clear lacquers.
[0003] Nanoparticles in polymeric coatings can improve properties
such as scratch resistance, UV protection or conductivity in a
targeted manner. Control of the surface modification and dispersing
of the nanoparticles determines the required transparent appearance
of the coatings and properties thereof.
[0004] Various approaches have been pursued in the past for
introduction of the nanoparticles into coating composition
formulations. In this context, the particles can be mixed directly
into the resin or curing agent component or into the coating
composition ready for application. In aqueous systems there is the
possibility of dispersing the particles in the aqueous phase. The
in situ preparation of the particles in one of the binder
components and adaptation of the surface to either the resin or the
curing agent component have furthermore been described.
[0005] From the practical point of view, it is advantageous to
disperse the nanoparticles as stable masterbatches in one of the
components, so that a long-term storage stability and a simple ease
of handling in the formulation of lacquers is ensured. In the end
use, the nanoparticles must likewise be readily dispersible in a
finely divided manner, so that advantageous properties such as
transparency, scratch resistance or conductivity result.
[0006] In practice, the nanoparticles are conventionally dispersed
into the resin component, into the aqueous phase or into the
finished mixture of curing agent and resin shortly before curing.
As a rule, for this it is necessary to adapt the surface of the
nanoparticles to the specific matrix of the coating composition or
of the adhesive. The disadvantage of simple mixing in of modified
nanoparticles is the dependency of the stability on the complete
formulation, i.e. on all the formulation constituents. Variation of
one parameter can lead here to demixing (Pilotek, Steffen;
Tabellion, Frank (2005), European Coatings Journal, 4, 170 et
seq.).
[0007] It is known from the prior art that coating compositions can
be prepared with silane-modified nanoparticles. For example, WO-A
02/24756 discloses coating compositions based on suspension
polymers and silane-modified nanoparticles. However, the polymers
described there are suspension and emulsion polymers. Suspension
polymerization is carried out in an aqueous phase, like emulsion
polymerization. Beads of solid, which are filtered off from the
aqueous phase, form the end product of the suspension.
[0008] WO-A 2006/008120 describes aqueous dispersions of polymeric
and/or oligomeric organic binders and inorganic nanoparticles. The
nanoparticles are surface-modified by addition of silane-functional
compounds. The disadvantage here, however, is that the gloss and
haze of the resulting coatings do not meet the high requirements of
automobile clear lacquers.
[0009] WO-A 03/095532 discloses aqueous dispersions of
hydrophilized polymers or oligomers which contain surface-modified
inorganic nanoparticles and at least one amphiphile. Possible
hydrophilic polymers are emulsion polymers, which are prepared in
an aqueous phase. The use of the amphiphiles, which are necessary
according to this teaching, is a disadvantage since these low
molecular weight alcohols must be included as solvents in the VOC
balance (volatile organic compounds). Furthermore, these are highly
reactive mono- or polyol compounds which co-react, for example,
with polyisocyanates during crosslinking of the binders and lead to
a reduced functionality up to chain termination. The network
build-up of the resulting lacquers impaired in this way leads to a
reduction in resistances.
[0010] It has now been found, surprisingly, that aqueous copolymers
which are modified with a certain class of silanes are suitable, in
combination with inorganic nanoparticles, for the production of
coatings having a significantly improved scratch resistance with
excellent gloss and very low haze (cloudiness).
[0011] The object of the present invention was thus to provide high
quality coating compositions, in particular as automobile clear
lacquers, which have an optimum gloss and haze and show an improved
scratch resistance. The dispersions should furthermore be
sufficiently stable to storage.
EMBODIMENTS OF THE INVENTION
[0012] An embodiment of the present invention is an aqueous
formulation comprising [0013] A) a silane-modified copolymer;
[0014] B) optionally surface-modified inorganic particles having an
average particle size (z-mean), as determined by means of dynamic
light scattering in dispersion, of less than 200 nm; and [0015] C)
water.
[0016] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-modified copolymer A)
comprises groups of general formula (1)
--Si(R.sup.1O).sub.2R.sup.2 (1) [0017] wherein [0018] R.sup.1 is a
C.sub.2- to C.sub.8-alkyl radical; and [0019] R.sup.2 is (R.sup.1O)
or a C.sub.1- to C.sub.5-alkyl radical.
[0020] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-modified copolymer A) is a
copolymer which is built up from [0021] I) a hydroxy-functional
hydrophobic polymer containing as builder monomers [0022] Ia)
(meth)acrylic acid esters having C.sub.1- to C.sub.18-hydrocarbon
radicals in the alcohol part and/or vinylaromatics and/or vinyl
esters; [0023] Ib) hydroxy-functional monomers; and [0024] IS1)
silane-functional monomers capable of polymerization; and [0025]
II) a hydroxy-functional hydrophilic polymer containing as builder
components [0026] IIa) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; [0027] IIb) hydroxy-functional
monomers; and [0028] IIc) acid-functional monomers.
[0029] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-modified copolymer A) is a
copolymer which is built up from [0030] I) a hydroxy-functional
hydrophobic polymer containing as builder monomers [0031] Ia)
(meth)acrylic acid esters having C.sub.1- to C.sub.18-hydrocarbon
radicals in the alcohol part and/or vinylaromatics and/or vinyl
esters; and [0032] Ib) hydroxy-functional monomers; and [0033] II)
a hydroxy-functional hydrophilic polymer containing as builder
components [0034] IIa) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; [0035] IIb) hydroxy-functional
monomers; [0036] IIc) acid-functional monomers; and [0037] IIS1)
silane-functional monomers capable of polymerization.
[0038] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-functional monomer IS1),
which is capable of polymerization, is a compound of the general
formula (2)
(R.sup.1O).sub.2R.sup.2Si--(CH.dbd.C.sub.1H.sub.2) (2) [0039]
wherein [0040] R.sup.1 is a C.sub.2- to C.sub.8-alkyl radical; and
[0041] R.sup.2 is (R.sup.1O) or a C.sub.1- to C.sub.5-alkyl
radical; [0042] and/or a compound of the general formula (3)
[0042]
(R.sup.1O).sub.2R.sup.2Si(CH.sub.2).sub.m--O(CO)--(CR.sup.3.dbd.C-
H.sub.2) (3) [0043] wherein [0044] R.sup.1 is a C.sub.2- to
C.sub.8-alkyl radical; [0045] R.sup.2 is (R.sup.1O) or a C.sub.1-
to C.sub.5-alkyl radical; [0046] R.sup.3 is H or CH.sub.3; and
[0047] m is 1 to 4.
[0048] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-functional monomer IIS1),
which is capable of polymerization, is a compound of the general
formula (2)
(R.sup.1O).sub.2R.sup.2Si--(CH.dbd.CH.sub.2) (2) [0049] wherein
[0050] R.sup.1 is a C.sub.2- to C.sub.8-alkyl radical; and [0051]
R.sup.2 is (R.sup.1O) or a C.sub.1- to C.sub.5-alkyl radical;
[0052] and/or a compound of the general formula (3)
[0052]
(R.sup.1O).sub.2R.sup.2Si(CH.sub.2).sub.m--O(CO)--(CR.sup.3.dbd.C-
H.sub.2) (3) [0053] wherein [0054] R.sup.1 is a C.sub.2- to
C.sub.8-alkyl radical; [0055] R.sup.2 is (R.sup.1O) or a C.sub.1-
to C.sub.5-alkyl radical; [0056] R.sup.3 is H or CH.sub.3; and
[0057] m is 1 to 4.
[0058] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-functional monomer IS1),
which are capable of polymerization, is selected from the group
consisting of vinyltriethoxysilane, vinyltrisisopropoxysilane,
vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane,
vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane,
3-(triethoxysilyl)-propyl methacrylate or
3-(tris-isopropoxysilyl)-propyl methacrylate,
vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane, and
vinyltri-t-butoxysilane.
[0059] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane-functional monomers IS1),
which are capable of polymerization, is selected from the group
consisting of vinyltriethoxysilane, vinyltrisisopropoxysilane,
vinyl-tris-(2-methoxyethoxy)silane, vinylmethyldiethoxysilane,
vinylmethyldiisopropoxysilane, vinylethyldiethoxysilane,
3-(triethoxysilyl)-propyl methacrylate or
3-(tris-isopropoxysilyl)-propyl methacrylate,
vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane, and
vinyltri-t-butoxysilane.
[0060] Another embodiment of the present invention is the above
aqueous formulation, wherein said silane functional copolymer A) is
a copolymer which is built up from [0061] I) a hydroxy-functional
hydrophobic polymer containing as builder monomers [0062] Ia)
(meth)acrylic acid esters having C.sub.1- to C.sub.18-hydrocarbon
radicals in the alcohol part and/or vinylaromatics and/or vinyl
esters; [0063] Ib) hydroxy-functional monomers; and [0064] II) a
hydroxy-functional hydrophilic polymer containing as builder
components [0065] IIa) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters; [0066] IIb) hydroxy-functional
monomers; [0067] IIc) acid-functional monomers; and [0068] IIS2)
monomers which contain at least one epoxide function in addition to
silane groups.
[0069] Another embodiment of the present invention is the above
aqueous formulation, wherein said monomers IIS2) are selected from
the group consisting of .gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyl-tris-isopropoxysilane,
.gamma.-glycidoxypropyl-diethoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-triethoxysilane, and
.beta.-(3,4-epoxycyclohexyl)-tris-isopropoxysilane.
[0070] Another embodiment of the present invention is the above
aqueous formulation, wherein said inorganic particles B) are
selected from the group consisting of inorganic oxides, mixed
oxides, carbides, borides, and nitrides of elements of main group
II to IV and/or elements of subgroup I to VIII of the periodic
table, including the lanthanides.
[0071] Another embodiment of the present invention is the above
aqueous formulation, wherein said inorganic particles B) are
inorganic nanoparticles in a colloidally disperse form in organic
solvents or in water.
[0072] Another embodiment of the present invention is the above
aqueous formulation, wherein said inorganic particles B) are
inorganic particles in the form of aqueous formulations.
[0073] Another embodiment of the present invention is the above
aqueous formulation, wherein said inorganic particles B) are
surface-modified inorganic nanoparticles.
[0074] Yet another embodiment of the present invention is an
aqueous coating composition comprising the above aqueous
formulation and at least one crosslinking agent D).
[0075] Yet another embodiment of the present invention is an
aqueous two-component coating composition comprising the above
aqueous formulation and a polyisocyanate.
[0076] Yet another embodiment of the present invention is a clear
lacquer comprising the above aqueous formulation.
DESCRIPTION OF THE INVENTION
[0077] The present invention therefore provides aqueous
formulations comprising [0078] A) a silane-modified copolymer,
[0079] B) inorganic particles which are optionally surface-modified
and have an average particle size (z-mean), determined by means of
dynamic light scattering in dispersion, of less than 200 nm and
[0080] C) c) water.
[0081] The silane-modified copolymer A) contains groups of the
general formula (1)
--Si(R.sup.1O).sub.2R.sup.2 (1) [0082] is in which [0083] R.sup.1
is a C.sub.2- to C.sub.8-alkyl, preferably a C.sub.3- to
C.sub.6-alkyl radical and [0084] R.sup.2 is (R.sup.1O) or a
C.sub.1- to C.sub.5-alkyl radical, preferably is (R.sup.1O) or a
C.sub.1- to C.sub.3-alkyl radical.
[0085] The aqueous formulations according to the invention comprise
20 to 59 parts by wt., preferably 25 to 48 parts by wt. and
particularly preferably 27.5 to 40 parts by wt. of copolymer A), 1
to 40 parts by wt., preferably 2 to 25 parts by wt. and
particularly preferably 2.5 to 15 parts by wt. of inorganic
nanoparticles B), 5 to 44 parts by wt., preferably 10 to 33 parts
by wt. and particularly preferably 12.5 to 25 parts by wt. of
crosslinking agent C and 35 to 74 parts by wt., preferably 40 to 63
parts by wt. and particularly preferably 45 to 57.5 parts by wt. of
water D).
[0086] In a first embodiment (a), component A) is a copolymer which
is built up from [0087] I) a hydroxy-functional hydrophobic polymer
containing as builder monomers [0088] Ia) (meth)acrylic acid esters
having C.sub.1- to C.sub.18-hydrocarbon radicals in the alcohol
part and/or vinylaromatics and/or vinyl esters, [0089] Ib)
hydroxy-functional monomers and [0090] IS1) silane-functional
monomers which are capable of polymerization, and [0091] II) a
hydroxy-functional hydrophilic polymer containing as builder
components [0092] IIa) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters, [0093] IIb) hydroxy-functional
monomers and [0094] IIc) acid-functional monomers.
[0095] This embodiment (.alpha.) is preferred.
[0096] In a further embodiment (.beta.), component A) is a
copolymer which is built up from [0097] I) a hydroxy-functional
hydrophobic polymer containing as builder monomers [0098] Ia)
(meth)acrylic acid esters having C.sub.1- to C.sub.18-hydrocarbon
radicals in the alcohol part and/or vinylaromatics and/or vinyl
esters, [0099] Ib) hydroxy-functional monomers and [0100] II) a
hydroxy-functional hydrophilic polymer containing as builder
components [0101] IIa) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters, [0102] IIb) hydroxy-functional
monomers, [0103] IIc) acid-functional monomers and [0104] IIS1)
silane-functional monomers which are capable of polymerization.
[0105] The content of monomers Ia)/IIa) in the copolymer A) in
embodiments (.alpha.) and (.beta.) is 34.3 to 89.3 parts by wt.,
preferably 51.8 to 84.8 parts by wt. and particularly preferably 58
to 81 parts by wt., the content of monomers Ib)/IIb) in the
copolymer A) is 10 to 65 parts by wt., preferably 13.5 to 46.5
parts by wt. and particularly preferably 17 to 40 parts by wt., the
content of monomers IIc) in the copolymer A) is 0.6 to 12 parts by
wt., preferably 1.2 to 5.5 parts by wt. and particularly preferably
1.25 to 3.5 parts by wt. and the content of monomers IS1)/IIS1) in
the copolymer A) is 0.1 to 12 parts by wt., preferably 0.5 to 5
parts by wt. and particularly preferably 0.75 to 3.5 parts by
wt.
[0106] Suitable silane-functional monomers IS1) and IIS1) which are
capable of polymerization are e.g. compounds of the general formula
(2)
(R.sup.1O).sub.2R.sup.2Si--(CH.dbd.CH.sub.2) (2) [0107] in which
[0108] R.sup.1 is a C.sub.2- to C.sub.8-alkyl, preferably a
C.sub.3- to C.sub.6-alkyl radical, [0109] R.sup.2 is (R.sup.1O) or
a C.sub.1- to C.sub.5-alkyl radical, preferably is (R.sup.1O) or a
C.sub.1- to C.sub.3-alkyl radical, and/or compounds of the general
formula (3)
[0109]
(R.sup.1O).sub.2R.sup.2Si(CH.sub.2).sub.m--O(CO)--(CR.sup.3.dbd.C-
H.sub.2) (3) [0110] in which [0111] R.sup.1 is a C.sub.2- to
C.sub.8-alkyl, preferably a C.sub.3-C.sub.6-alkyl radical, [0112]
R.sup.2 is (R.sup.1O) or a C.sub.1- to C.sub.5-alkyl radical,
preferably is (R.sup.1O) or a C.sub.1- to C.sub.3-alkyl radical,
[0113] R.sup.3 is H or CH.sub.3 and [0114] m is 1 to 4, preferably
3.
[0115] Examples of suitable silane-functional monomers IS1) and
IIS1) which are capable of polymerization are vinyltriethoxysilane,
vinyltrisisopropoxysilane, vinyl-tris-(2-methoxy)silane,
vinylmethyldiethoxysilane, vinylmethyldiisopropoxysilane,
vinylethyldiethoxysilane, 3-(triethoxysilyl)-propyl methacrylate or
3-(tris-isopropoxysilyl)-propyl methacrylate,
vinylphenyldiethoxysilane, vinylphenylmethylethoxysilane or
vinyltri-t-butoxysilane. Vinyltrisisopropoxysilane is preferred
[0116] It is also possible for component A) (embodiment (.gamma.))
to be a copolymer which is built up from [0117] I) a
hydroxy-functional hydrophobic polymer containing as builder
monomers [0118] Ia) (meth)acrylic acid esters having C.sub.1- to
C.sub.18-hydrocarbon radicals in the alcohol part and/or
vinylaromatics and/or vinyl esters, [0119] Ib) hydroxy-functional
monomers and [0120] II) a hydroxy-functional hydrophilic polymer
containing as builder components [0121] IIa) (meth)acrylic acid
esters having C.sub.1- to C.sub.18-hydrocarbon radicals in the
alcohol part and/or vinylaromatics and/or vinyl esters, [0122] IIb)
hydroxy-functional monomers, [0123] IIc) acid-functional monomers
and [0124] IIS2) monomers which contain at least one epoxide
function in addition to silane groups.
[0125] The content of monomers Ia)/IIa) in the copolymer A) in
embodiment (.gamma.) is 33.8 to 88.8 parts by wt., preferably 49.1
to 83.9 parts by wt. and particularly preferably 56 to 79.5 parts
by wt., the content of monomers Ib)/IIb) in the copolymer A) is 10
to 65 parts by wt, preferably 13.5 to 48.3 parts by wt. and
particularly preferably 17 to 40.5 parts by wt., the content of
monomers IIe) in the copolymer A) is 1 to 15 parts by wt.,
preferably 1.85 to 8 parts by wt. and particularly preferably 2.5
to 6.5 parts by wt. and the content of monomers IIS2) in the
copolymer A) is 0.2 to 12 parts by wt., preferably 0.75 to 5.5
parts by wt. and particularly preferably 1 to 4.5 parts by wt.
[0126] Examples of suitable monomers IIS2) which contain at least
one epoxide function in addition to silane groups are
.gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyl-tris-isopropoxysilane,
.gamma.-glycidoxypropyl-diethoxy-methylsilane,
glycidoxypropyl-di-isopropoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-triethoxysilane,
.beta.-(3,4-epoxycyclohexyl)-tris-isopropoxysilane,
.beta.-(3,4-epoxycyclohexyl)-diethoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-di-isopropoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-diethoxy-ethylsilane or
.beta.-(3,4-epoxycyclohexyl)-di-isopropoxy-ethylsilane.
.gamma.-Glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyl-tris-isopropoxysilane,
.gamma.-glycidoxypropyl-diethoxy-methylsilane,
.beta.-(3,4-epoxycyclohexyl)-triethoxysilane or
.beta.-(3,4-epoxycyclohexyl)-tris-isopropoxysilane is preferred and
.gamma.-glycidoxypropyl-tris-isopropoxysilane,
.gamma.-glycidoxypropyl-diethoxy-methylsilane and
.beta.-(3,4-epoxycyclohexyl)-tris-isopropoxysilane are particularly
preferred.
[0127] Suitable monomers Ia)/IIa) are the esterification products
of acrylic or methacrylic acid with simple alcohols, e.g. ethyl
acrylate, ethyl methacrylate, n-butyl acrylate, iso-butyl acrylate,
tert-butyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl
methacrylate, methyl methacrylate, n-butyl methacrylate, iso-butyl
methacrylate, tert-butyl methacrylate, cyclohexyl acrylate or
cyclohexyl methacrylate, and vinylphenyls, such as styrene,
vinyltoluene, .alpha.-methylstyrene or mixtures of these and other
monomers.
[0128] Further compounds of the (meth)acrylic acid ester type which
are suitable as monomers Ia)/IIa) are the esters of acrylic acid or
methacrylic acid with linear aliphatic monools having eight carbon
atoms, such as e.g. the so-called fatty alcohols (monools), or with
linear aliphatic saturated alcohols which are derived from
naturally occurring fatty acids, such as lauryl (C.sub.12),
myristyl (C.sub.14), palmityl (C.sub.16) or stearyl (C.sub.18)
alcohol. Aliphatic saturated alcohols which are likewise suitable
are e.g. n-octanol, nonanol or n-decanol. Suitable monomers of the
(meth)acrylic acid ester type which contain an aliphatic radical
having at least eight carbon atoms are e.g. n-octyl acrylate, nonyl
acrylate, n-decyl acrylate, lauryl acrylate, myristyl acrylate,
palmityl acrylate, stearyl acrylate and the corresponding
methacrylic acid derivative.
[0129] Monomers of the abovementioned type which are furthermore
suitable are esters of acrylic acid or methacrylic acid with
cycloaliphatic alcohols (monools) having at least 10 carbon atoms,
such as e.g. i-bornyl acrylate, n-bornyl methacrylate,
dihydroxydicyclopentadienyl acrylate or 3,3,5-trimethylcyclohexyl
methacrylate.
[0130] Suitable monomers Ia/IIa) are furthermore the esterification
products of vinyl alcohol with linear or branched aliphatic
carboxylic acids, such as, for example, vinyl acetate, vinyl
propionate or vinyl butyrate. Vinyl esters which are preferred are
those of branched aliphatic carboxylic acids of the general formula
(4)
##STR00001##
in which R.sup.1 and R.sup.2 are saturated alkyl groups containing
together 6, 7 or 8 C atoms, corresponding to the compounds
VeoVa.TM. (Hexion Specialty Chemicals, USA) 9, 10 und 11.
[0131] The monomers mentioned differ with respect to the glass
transition temperature of their homopolymers:
TABLE-US-00001 Monomer T.sub.G [.degree. C.] VeoVa .TM. 9 +70 VeoVa
.TM. 10 -3 VeoVa .TM. 11 -40
[0132] Preferred monomers Ia)/IIa) are n-butyl acrylate, iso-butyl
acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, methyl
methacrylate, n-butyl methacrylate, iso-butyl methacrylate,
tert-butyl methacrylate, cyclohexyl acrylate, cyclohexyl
methacrylate, i-bornyl acrylate, i-bornyl methacrylate and styrene,
and n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate,
n-butyl methacrylate, tert-butyl methacrylate, cyclohexyl
methacrylate, i-bornyl acrylate, i-bornyl methacrylate and styrene
are particularly preferred.
[0133] Further monomers which are capable of free-radical
copolymerization can also optionally be employed as compounds of
component Ia/IIa) in the preparation of copolymer A). These can be,
for example, derivatives of acrylic or methacrylic acid, such as
acrylamide, methacrylamide, acrylonitrile or methacrylonitrile.
Vinyl ethers or vinyl acetates are furthermore optionally possible.
Possible further components Ia/Ia) which are optionally to be
employed in minor amounts are (meth)acrylate monomers which are
difunctional or more than difunctional and/or vinyl monomers, such
as e.g. hexanediol di(meth)acrylate or divinylbenzene.
[0134] Suitable hydroxy-functional monomers Ib)/IIb) are e.g.
2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate,
2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl
acrylate or 4-hydroxybutyl methacrylate. Preferred monomers
Ib)/IIb) are 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
2-hydroxypropyl methacrylate or 4-hydroxybutyl acrylate and
mixtures of these compounds.
[0135] Suitable olefinically unsaturated acid-functional monomers
IIc) are sulfonic or carboxylic acid-functional monomers,
preferably carboxylic acid-functional monomers, such as acrylic
acid, methacrylic acid, .beta.-carboxyethyl acrylate, crotonic
acid, fumaric acid, maleic anhydride, itaconic acid or monoalkyl
esters of dibasic acids or anhydrides, such as e.g. maleic acid
monoalkyl esters, and acrylic or methacrylic acid are
preferred.
[0136] Unsaturated compounds which can undergo free-radical
polymerization and have phosphate or phosphonate, or sulfonic acid
or sulfonate groups, such as are described e.g., in WO-A 00/39181
(p. 8, 1. 13-p. 9, 1. 19) are furthermore also suitable as
compounds of component IIc).
[0137] Suitable initiators for the polymerization reaction are
organic peroxides, such as di-tert-butyl peroxide or tert-butyl
peroxy-2-ethylhexanoate, and azo compounds, such as azodiisobutyric
acid nitrite (AIBN). The amounts of initiator employed depend on
the desired molecular weight. For reasons of process reliability
and easier handling, peroxide initiators can also be employed as a
solution in suitable organic solvents of the type mentioned
below.
[0138] The preparation of the copolymer A) is carried out by a
copolymerization, initiated by free radicals, of the monomer
mixture I) and II) in organic solvent (mixtures). The amount of
organic solvents is chosen such that the resulting solutions of the
copolymers A) have a solids content of from 95 to 60 wt. %,
preferably 92.5 to 80 wt. %.
[0139] The procedure for polymerization of the unsaturated monomers
is familiar per se to the person skilled in the art. Typically, for
this, a suitable solvent is initially introduced into a reaction
vessel and the unsaturated monomers are polymerized in the feed
process using a free radical initiator.
[0140] Possible suitable organic solvents are any desired solvents
known in lacquer technology, preferably those which are
conventionally employed as co-solvents in aqueous dispersions, such
as e.g. alcohols, ethers, alcohols containing ether groups, esters,
ketones or non-polar hydrocarbons, e.g. aliphatic or aromatic
hydrocarbons or mixtures of these solvents.
[0141] The preparation of component A) in embodiment (.alpha.) or
(.beta.) is carried out by a two-stage addition and polymerization
of the monomer mixtures I) and II) in the sequence mentioned. In
this context, in a first step (i) a hydroxy-functional hydrophobic
polymer I) having an OH number of from 12 to 250 mg of KOH/g of
solid, preferably from 50 to 200 mg of KOH/g of solid, is prepared
from the monomers Ia) and Ib). In a subsequent step (ii), the
hydroxy-functional hydrophilic polymer II) is prepared from the
monomers IIa) to IIc) in the solution of the polymer I) obtained
from step (i), this hydroxy-functional hydrophilic polymer II)
having an OH number of from 20 to 250 mg of KOH/g of solid,
preferably from 120 to 220 mg of KOH/g of solid, and an acid number
of from 50 to 250 mg of KOH/g of solid, preferably from 110 to 200
mg of KOH/g of solid. Silane-functional monomers IS1) are
copolymerized accordingly with monomer mixture Ia) and Ib), or
IIS2) with monomer mixture Ia), IIb) and IIc).
[0142] The preparation of component A) in embodiment (.gamma.) is
carried out by a two-stage addition and polymerization of the
monomer mixtures I) and II) in the sequence mentioned. In this
context, in a first step (i) a hydroxy-functional hydrophobic
polymer I) having an OH number of from 12 to 250 mg of KOH/g of
solid, preferably from 50 to 200 mg of KOH/g of solid, is prepared
from the monomers Ia) and Ib). In a subsequent step (ii), the
hydroxy-functional hydrophilic polymer II) is prepared from the
monomers IIa) to IIc) and IIS2) in the solution of the polymer I)
obtained from step (i). In this step, according to the free-radical
polymerization of components IIa) to IIc), the reaction of the
epoxide groups of IIS2) with free carboxylic acid group is carried
out simultaneously. This reaction can optionally be catalyzed by
suitable esterification catalysts, such as e.g. dibutyltin
dilaurate or tin dioctoate. The hydroxy-functional hydrophilic
polymer II) has an OH number of from 20 to 250 mg of KOH/g of
solid, preferably from 120 to 220 mg of KOH/g of solid and an acid
number of from 50 to 250 mg of KOH/g of solid, preferably from 110
to 200 mg of KOH/g of solid.
[0143] Organic amines or water-soluble inorganic bases can be
employed for neutralization of the carboxyl groups polymerized into
the copolymer A). N-Methylmorpholine, triethylamine,
dimethylethanolamine, dimethylisopropanolamine,
methyl-diethanolamine, triethanolamine or ethyl-diisopropylamine
are preferred. Diethyl-ethanolamine, butanolamine, morpholine,
2-aminomethyl-2-methyl-propanol or isophoronediamine are likewise
suitable.
[0144] The neutralizing agent is added in amounts such that the
degree of neutralization is 70 to 130%, preferably 90 to 105% of
the carboxyl groups, an amount of neutralizing agent such that
after conversion of all the carboxyl groups into the salt form free
neutralizing agent is still present particularly preferably being
added. This corresponds to a degree of neutralization of
>100%.
[0145] The resulting hydrophilic polymers A) are then dispersed by
addition of water or by transfer into water. The pH of the aqueous
dispersion is 6.0 to 11.0, preferably 7.5 to 10.0, and the solids
content is 35 to 65 wt. %, preferably 40 to 55 wt. %.
[0146] Possible particles B) are inorganic oxides, mixed oxides,
hydroxides, sulfates, carbonates, carbides, borides and nitrides of
elements of main group II to IV and/or elements of subgroup I to
VIII of the periodic table, including the lanthanides. Preferred
particles B) are silicon oxide, aluminium oxide, cerium oxide,
zirconium oxide, niobium oxide and titanium oxide, and silicon
oxide nanoparticles are particularly preferred.
[0147] The particles employed preferably have average particles
sizes, determined as the z-mean by means of dynamic light
scattering in dispersion, of from 5 to 100 nm, particularly
preferably 5 to 50 nm.
[0148] Preferably at least 75%, particularly preferably at least
90%, very particularly preferably at least 95% of all the particles
employed have the sizes defined above.
[0149] The optionally surface-modified nanoparticles B) are
introduced during or after the preparation of the modified
copolymer A). This can be carried out by simply stirring in the
particles. However, the use of an increased dispersing energy, such
as, for example, by ultrasound, jet dispersion or high-speed
stirrers according to the rotor-stator principle, is also
conceivable. Simple mechanical stirring-in is preferred.
[0150] The particles B) can in principle be employed both in powder
form and in the form of colloidal suspensions or dispersions in
suitable solvents. The inorganic nanoparticles B) are preferably
employed in a colloidally disperse form in organic solvents
(organosols) or in water.
[0151] Suitable solvents for the organosols are methanol, ethanol,
i-propanol, acetone, 2-butanone, methyl isobutyl ketone, butyl
acetate, ethyl acetate, 1-methoxy-2-propyl acetate, toluene,
xylene, 1,4-dioxane, diacetone alcohol, ethylene glycol n-propyl
ether or any desired mixtures of such solvents. Suitable organosols
have a solids content of from 10 to 60 wt. %, preferably 15 to 50
wt. %. Suitable organosols are, for example, silicon dioxide
organosols, such as are obtainable e.g. under the trade names
Organosilicasol.RTM. and Suncolloid.RTM. (Nissan Chem. Am. Corp.)
or under the name Highlink.RTM.NanO G (Clariant GmbH).
[0152] If the nanoparticles are employed in organic solvents
(organosols), these are mixed with the copolymers A) before
dispersion thereof with water. The resulting mixtures are then
dispersed in water by addition of water or by transfer into water.
The mixing of the organosols with copolymers A) can be carried out
either before or after neutralization of the carboxyl groups
polymerized into coopolymer A). If required, the organic solvent of
the organosol can be removed by distillation before or after the
dispersing with water, preferably after the dispersing with
water.
[0153] In the context of the present invention, inorganic particles
B) are furthermore preferably used in the form of their aqueous
formulations. The use of inorganic particles B) in the form of
aqueous formulations of surface-modified inorganic nanoparticles is
particularly preferred. These can be modified by silanization, for
example, before or at the same time as the incorporation into the
silane-modified polymeric organic binder or an aqueous dispersion
of the silane-modified polymeric organic binder. This method is
known in principle from the literature and is described, for
example, in DE-A 19846660 or WO 03/44099.
[0154] The surface of the inorganic nanoparticies can furthermore
be modified adsorptively/associatively by surfactants or block
copolymers, as described, for example, in WO 2006/008120 and
Foerster, S. & Antonietti, M., Advanced Materials, 10, no. 3,
(1998) 195.
[0155] Preferred surface modification is the silanization with
alkoxysilanes and/or chlorosilanes. Partial modification with
.gamma.-glycidoxypropyltrimethoxysilane corresponding to WO
2004/035474 is particularly preferred.
[0156] Preferred aqueous commercial nanoparticle dispersions are
Levasils.RTM. (H. C. Starck GmbH, Goslar, Germany) and
Bindzils.RTM. (EKA Chemical AB, Bohus, Sweden). Aqueous dispersion
of Bindzil.RTM. CC 30 and Bindzil.RTM. CC 40 from EKA (EKA Chemical
AB, Bohus, Sweden) are particularly preferably employed.
[0157] If the nanoparticles are employed in aqueous form, these are
added to the aqueous dispersions of the copolymers A). In a further
embodiment, the aqueous nanoparticle colloids are added to the
copolymers A) after neutralization of the carboxyl groups
polymerized into copolymer A) and the mixture is optionally then
diluted further with water.
[0158] The aqueous formulations according to the invention can be
processed to aqueous coating compositions. In this context, by
combination with crosslinking agents D), depending on the
reactivity or, where appropriate, blocking of the crosslinking
agents, both one-component lacquers and two-component lacquers can
be prepared. One-component lacquers in the context of the present
invention are to be understood here as meaning coating compositions
in which the binder component and crosslinking component can be
stored together without a crosslinking reaction taking place to an
extent which is noticeable or harmful for the later application.
The crosslinking reaction takes place only on application after
activation of the crosslinking agent. This activation can be
effected e.g. by increasing the temperature. Two-component lacquers
in the context of the present invention are understood as meaning
coating compositions in which the binder component and crosslinking
component must be stored in separate vessels because of their high
reactivity. The two components are mixed only shortly before
application and then in general react without additional
activation. However, catalysts can also be employed or higher
temperatures applied in order to accelerate the crosslinking
reaction.
[0159] The present invention therefore also provides aqueous
coating compositions comprising the aqueous formulations according
to the invention and at least one crosslinking agent D).
[0160] Suitable crosslinking agents D) are, for example,
polyisocyanate crosslinking agents, amide- and amine-formaldehyde
resins, phenolic resins and aldehyde and ketone resins, such as
e.g. phenol-formaldehyde resins, resols, furan resins, urea resins,
carbamic acid ester resins, triazine resins, melamine resins,
benzoguanamine resins, cyanamide resins and aniline resins, such as
are described in "Lackkunstharze", H. Wagner, H. F. Sarx, Carl
Hanser Verlag Munich, 1971.
[0161] Preferred crosslinking agents D) are free or blocked
polyisocyanates, which can optionally be hydrophilically modified,
and/or non-blocked polyisocyanates which are at least partly
hydrophilically modified.
[0162] The present invention likewise provides aqueous
two-component (2C) coating compositions comprising the aqueous
formulations according to the invention and a polyisocyanate.
Preferably, at least a proportion of the polyisocyanate is
hydrophilically modified.
[0163] Suitable polyisocyanates are difunctional isocyanates, such
as e.g. isophorone-diisocyanate, hexamethylene-diisocyanate, 2,4-
or 2,6-diisocyanatotoluene, 4,4'-diphenylmethane-diisocyanate
and/or higher molecular weight trimers thereof, biurets, urethanes,
iminooxadiazinedione and/or allophanates. The use of low-viscosity,
optionally hydrophilized polyisocyanates of the abovementioned type
based on aliphatic or cycloaliphatic isocyanates is particularly
preferred.
[0164] For the blocking, the abovementioned polyisocyanates are
reacted with blocking agents, such as e.g. methanol, ethanol,
butanol, hexanol, benzyl alcohol, acetoxime, butanone oxime,
caprolactam, phenol, diethyl malonate, dimethyl malonate,
dimethylpyrazole, triazole, dimethyltriazole, ethyl acetoacetate,
diisopropylamine, dibutylamine, tert-butylbenzylamine,
cyclopentanone carboxyethyl ester, dicyclohexylamine and/or
tert-butylisopropylamine.
[0165] The non-blocked and blocked polyisocyanates can also be
converted into a water-dispersible form by incorporation of
hydrophilic groups, such as e.g. carboxylate, sulfonate and/or
polyethylene oxide structures, and employed in this way in
combination with the formulations according to the invention. The
blocked polyisocyanates mentioned can also be prepared co-using
hydroxy- or amino-functional, also higher molecular weight
components, such as e.g. diols, triols, amino alcohols, polyesters,
polyethers, polycarbonates and mixtures of the raw materials
mentioned and/or other raw materials.
[0166] The polyisocyanates employed as crosslinking agent D) in
general have a viscosity at 23.degree. C. of from 10 to 5,000 mPas
and, if desired for adjusting the viscosity, can also be employed
as a mixture with small amounts of inert solvents.
[0167] The use of mixtures of various crosslinking agents D) is of
course also possible in principle.
[0168] The conventional auxiliary substances and additives of
lacquer technology, such as e.g. defoaming agents, thickening
agents, pigments, dispersing auxiliaries, catalysts, skin
prevention agents, antisettling agents or emulsifiers, can be added
before, during or after the preparation of the aqueous formulations
according to the invention.
[0169] The aqueous coating compositions comprising the formulations
according to the invention are suitable for all fields of use in
which aqueous paint and coating systems with high requirements on
the resistance of the films are used, e.g. for coating of mineral
building material surfaces, lacquering and sealing of wood and wood
materials, coating of metallic surfaces (metal coating), coating
and lacquering of asphalt- or bitumen-containing coverings,
lacquering and sealing of diverse surfaces of plastic (coating of
plastics) and as high gloss lacquers.
[0170] The aqueous coating compositions comprising the formulations
according to the invention are employed for the preparation of
primers, fillers, pigmented or transparent top lacquers, clear
lacquers and high gloss lacquers as well as one-coat lacquers,
which can be used in individual or series application, e.g. in the
field of industrial lacquering and automobile first and repair
lacquering.
[0171] Curing of the aqueous coating compositions comprising the
formulations according to the invention is typically carried out in
this context at temperatures of from 0 to 60.degree. C., preferably
from 18 to 130.degree. C.
[0172] These coatings have, together with very good optical
properties of the film, a high level of scratch resistance,
resistance to solvents and chemicals, good weather resistance, high
hardness and rapid drying.
[0173] The coatings can be produced by the various spraying
processes, such as, for example, pneumatically or by airless or
electrostatic spraying processes, using one- or optionally
two-component spraying installations. However, the lacquers and
coating compositions comprising the aqueous coating compositions
according to the invention can also be applied by other methods,
for example by brushing, rolling or knife coating.
[0174] All the references described above are incorporated by
reference in their entireties for all useful purposes.
[0175] While there is shown and described certain specific
structures embodying the invention, it will be manifest to those
skilled in the art that various modifications and rearrangements of
the parts may be made without departing from the spirit and scope
of the underlying inventive concept and that the same is not
limited to the particular forms herein shown and described.
EXAMPLES
[0176] Unless noted otherwise, the percent data are to be
understood as percent by weight.
[0177] The hydroxyl number (OH number) was determined in accordance
with DIN 53240-2.
[0178] The viscosity was determined by means of a rotary viscometer
"Paar Physica MC R51" in accordance with DIN EN ISO 3219.
[0179] The acid number was determined in accordance with DIN EN ISO
2114.
Determination of the Particle Size
[0180] The particle sizes were determined by means of dynamic light
scattering using an HPPS particle size analyzer (Malvern,
Worcestershire, UK). The evaluation was performed via the
Dispersion Technology software 4.10. To avoid multiple scattering,
a highly dilute dispersion of the nanoparticles was prepared. One
drop of a dilute nanoparticle dispersion (approx. 0.1-10%) was
introduced into a cell containing approx. 2 ml of the same solvent
as the dispersion, the cell was shaken and measurement was carried
out in the HPPS analyzer at 20 to 25.degree. C. As is generally
known to the person skilled in the art, the relevant parameters of
the dispersing medium--temperature, viscosity and refractive
index--were entered into the software beforehand. In the case of
organic solvents, a glass cell was employed. An intensity- and
volume-particle diameter curve and the z-mean for the particle
diameter were obtained as the result. It was ensured that the
polydispersity index was <0.5. [0181] Bayhydur.RTM. XP 2655:
hydrophilic aliphatic polyisocyanate based on
hexamethylene-diisocyanate, isocyanate content: 21.2.+-.0.5% (Bayer
MaterialScience AG/Leverkusen, Germany) [0182] Bindzil.RTM. CC40:
40% strength colloidally disperse surface-modified silicon dioxide
in water, average particle size 12 nm according to the manufacturer
(EKA Chemical AB, Bohus, Sweden); a z-average particle size of
approx. 29 nm was obtained by means of dynamic light scattering
[0183] Byk.RTM. 325: flow auxiliary (Byk-Chemie GmbH, Wesel,
Germany) [0184] Byk.RTM. 345: wetting additive (Byk-Chemie GmbH,
Wesel, Germany) [0185] CoatOSil.RTM. 1706:
vinyl-tris-1-propoxysilane (Momentive/Leverkusen, Germany) [0186]
Desmodur.RTM. XP 2410: aliphatic polyisocyanates, isocyanate
content: 23.5.+-.0.5% (Bayer MaterialScience AG/Leverkusen,
Germany) [0187] Dowanol.RTM. PnB: solvent (Dow Chem. Corp., Horgen,
Switzerland) [0188] Organosilicasol.RTM. MEK-ST: 36 wt. % strength
colloidally disperse silicon dioxide in 2-butanone, average
particle size 10-15 nm according to the manufacturer (Nissan Chem.
Am. Corp., Houston/TX, USA); a z-average particle size of approx.
15-40 nm was obtained by means of dynamic light scattering [0189]
Rhodiasolv.RTM. RPDE: solvent (Rhodia Syntech GmbH, Frankfurt a.
M., Germany)
Comparison Example 1
[0190] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 139 g of styrene and 90.4 g of 2-ethylhexyl acrylate
was metered in during the course of 3.5 hours, and immediately
thereafter a mixture 3) of 63.8 g of styrene, 90 g of hydroxyethyl
acrylate, 50 g of butyl acrylate and 28.7 g of methacrylic acid was
metered in during the course of 1.5 hours. In parallel with mixture
2) and 3), a mixture 4) of 14.5 g of di-tert-butyl peroxide in 14.5
g of Dowanol.RTM. PnB was metered in over a period of 5 hours. A
mixture 5) of 4 g of di-tert-butyl peroxide in 4 g of Dowanol.RTM.
PnB was then metered in over a period of 1 hour. The mixture was
then cooled to 100.degree. C. and 31.2 g of
N,N-dimethylethanolamine were added. After homogenizing for 30
minutes, dispersing was carried out with 1,595 g of water at
80.degree. C. over a period of 2 hours. A copolymer dispersion
having the following data was obtained:
TABLE-US-00002 OH content (calculated for solids) 4.5% Acid number
(solids) 15.5 mg of KOH/g Solids content 40.1% Viscosity 580
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 105 nm Cosolvent 7.8 wt.
%
Comparison Example 2
[0191] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 139 g of styrene and 90.4 g of 2-ethylhexyl acrylate
was metered in during the course of 3.5 hours, and immediately
thereafter a mixture 3) of 63.8 g of styrene, 90 g of hydroxyethyl
acrylate, 50 g of butyl acrylate and 28.7 g of methacrylic acid was
metered in during the course of 1.5 hours. In parallel with mixture
2) and 3), a mixture 4) of 14.5 g of di-tert-butyl peroxide in 14.5
g of Dowanol.RTM. PnB was metered in over a period of 5 hours. A
mixture 5) of 4 g of di-tert-butyl peroxide in 4 g of Dowanol.RTM.
PnB was then metered in over a period of 1 hour. The mixture was
then cooled to 70.degree. C. 218 g of a 36 wt. % strength colloidal
dispersion of silicon dioxide in methyl ethyl ketone
(Organosilicasol.RTM. MEK-ST, Nissan Chem. Am. Corp.) were
introduced into this melt. 31.2 g of N,N-dimethylethanolamine were
then added, the mixture was homogenized for 30 minutes and
dispersing was carried out with 1,690 g of water at approx.
60.degree. C. over a period of 2 hours. The methyl ethyl ketone was
then distilled off in vacuo. A copolymer dispersion having the
following data was obtained:
TABLE-US-00003 OH content (calculated for solids) 4.2% Acid number
(solids) 14.5 mg of KOH/g Solids content 40.7% Viscosity 430
mPas.sub.23 .degree. C. pH (10% strength in water) 8.2 Degree of
neutralization 105% Average particle size 96 nm Cosolvent 7.4 wt.
%
Comparison Example 3
[0192] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 139 g of styrene and 90.4 g of 2-ethylhexyl acrylate
was metered in during the course of 3.5 hours, and immediately
thereafter a mixture 3) of 63.8 g of styrene, 90 g of hydroxyethyl
acrylate, 50 g of butyl acrylate and 28.7 g of methacrylic acid was
metered in during the course of 1.5 hours. In parallel with mixture
2) and 3), a mixture 4) of 14.5 g of di-tert-butyl peroxide in 14.5
g of Dowanol.RTM. PnB was metered in over a period of 5 hours. A
mixture 5) of 4 g of di-tert-butyl peroxide in 4 g of Dowanol.RTM.
PnB was then metered in over a period of 1 hour. The mixture was
then cooled to 70.degree. C. 436 g of a 36 wt. % strength colloidal
dispersion of silicon dioxide in methyl ethyl ketone
(Organosilicasol.RTM. MEK-ST, Nissan Chem. Am. Corp.) were
introduced into this melt. 31.2 g of N,N-dimethylethanolamine were
then added, the mixture was homogenized for 30 minutes and
dispersing was carried out with 1,790 g of water at approx.
60.degree. C. over a period of 2 hours. The methyl ethyl ketone was
then distilled off in vacuo. A copolymer dispersion having the
following data was obtained:
TABLE-US-00004 OH content (calculated for solids) 4.0% Acid number
(solids) 13.5 mg of KOH/g Solids content 40.3% Viscosity 440
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 135 nm Cosolvent 7.0 wt.
%
Comparison Example 4
[0193] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 139 g of styrene and 90.4 g of 2-ethylhexyl acrylate
was metered in during the course of 3.5 hours, and immediately
thereafter a mixture 3) of 63.8 g of styrene, 90 g of hydroxyethyl
acrylate, 50 g of butyl acrylate and 28.7 g of methacrylic acid was
metered in during the course of 1.5 hours. In parallel with mixture
2) and 3), a mixture 4) of 14.5 g of di-tert-butyl peroxide in 14.5
g of Dowanol.RTM. PnB was metered in over a period of 5 hours. A
mixture 5) of 4 g of di-tert-butyl peroxide in 4 g of Dowanol.RTM.
PnB was then metered in over a period of 1 hour. The mixture was
then cooled to 70.degree. C. 680 g of a 36 wt. % strength colloidal
dispersion of silicon dioxide in methyl ethyl ketone
(Organosilicasol.RTM. MEK-ST, Nissan Chem. Am. Corp.) were
introduced into this melt. 31.2 g of N,N-dimethylethanolamine were
then added, the mixture was homogenized for 30 minutes and
dispersing was carried out with 1,595 g of water at approx.
60.degree. C. over a period of 2 hours. The methyl ethyl ketone was
then distilled off in vacuo. A copolymer dispersion having the
following data was obtained:
TABLE-US-00005 OH content (calculated for solids) 3.8% Acid number
(solids) 12.7 mg of KOH/g Solids content 44.3% Viscosity 840
mPas.sub.23 .degree. C. pH (10% strength in water) 8.6 Degree of
neutralization 105% Average particle size 153 nm Cosolvent 7.2 wt.
%
Comparison Example 5
[0194] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 126.5 g of styrene, 90.4 g of 2-ethylhexyl acrylate
and 12.5 g of CoatOSil.RTM. 1706 was metered in during the course
of 3.5 hours, and immediately thereafter a mixture 3) of 63.8 g of
styrene, 90 g of hydroxyethyl acrylate, 50 g of butyl acrylate and
28.7 g of methacrylic acid was metered in during the course of 1.5
hours. In parallel with mixture 2) and 3), a mixture 4) of 14.5 g
of di-tert-butyl peroxide in 14.5 g of Dowanol.RTM. PnB was metered
in over a period of 5 hours. A mixture 5) of 4 g of di-tert-butyl
peroxide in 4 g of Dowanol.RTM. PnB was then metered in over a
period of 1 hour. The mixture was then cooled to 100.degree. C. and
31.2 g of N,N-dimethylethanolamine were added. After homogenizing
for 30 minutes, dispersing was carried out with 1,595 g of water at
80.degree. C. over a period of 2 hours. A copolymer dispersion
having the following data was obtained:
TABLE-US-00006 OH content (calculated for solids) 4.5% Acid number
(solids) 15.5 mg of KOH/g Solids content 40.2% Viscosity 500
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 100 nm Cosolvent 7.8 wt.
%
Example 6
[0195] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 126.5 g of styrene, 90.4 g of 2-ethylhexyl acrylate
and 12.5 g of CoatOSil.RTM. 1706 was metered in during the course
of 3.5 hours, and immediately thereafter a mixture 3) of 63.8 g of
styrene, 90 g of hydroxyethyl acrylate, 50 g of butyl acrylate and
28.7 g of methacrylic acid was metered in during the course of 1.5
hours. In parallel with mixture 2) and 3), a mixture 4) of 14.5 g
of di-tert-butyl peroxide in 14.5 g of Dowanol.RTM. PnB was metered
in over a period of 5 hours. A mixture 5) of 4 g of di-tert-butyl
peroxide in 4 g of Dowanol.RTM. PnB was then metered in over a
period of 1 hour. The mixture was then cooled to 70.degree. C. 436
g of a 36 wt. % strength colloidal dispersion of silicon dioxide in
methyl ethyl ketone (Organosilicasol.RTM. MEK-ST, Nissan Chem. Am.
Corp.) were introduced into this melt. 31.2 g of
N,N-dimethylethanolamine were then added, the mixture was
homogenized for 30 minutes and dispersing was carried out with
1,790 g of water at approx. 60.degree. C. over a period of 2 hours.
The methyl ethyl ketone was then distilled off in vacuo. A
copolymer dispersion having the following data was obtained:
TABLE-US-00007 OH content (calculated for solids) 4.0% Acid number
(solids) 13.5 mg of KOH/g Solids content 40.3% Viscosity 370
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 125 nm Cosolvent 7.0 wt.
%
Example 7
[0196] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 126.5 g of styrene, 90.4 g of 2-ethylhexyl acrylate
and 12.5 g of CoatOSil.RTM. 1706 was metered in during the course
of 3.5 hours, and immediately thereafter a mixture 3) of 63.8 g of
styrene, 90 g of hydroxyethyl acrylate, 50 g of butyl acrylate and
28.7 g of methacrylic acid was metered in during the course of 1.5
hours. In parallel with mixture 2) and 3), a mixture 4) of 14.5 g
of di-tert-butyl peroxide in 14.5 g of Dowanol.RTM. PnB was metered
in over a period of 5 hours. A mixture 5) of 4 g of di-tert-butyl
peroxide in 4 g of Dowanol.RTM. PnB was then metered in over a
period of 1 hour. The mixture was then cooled to 70.degree. C. 680
g of a 36 wt. % strength colloidal dispersion of silicon dioxide in
methyl ethyl ketone (Organosilicasol.RTM. MEK-ST, Nissan Chem. Am.
Corp.) were introduced into this melt. 31.2 g of
N,N-dimethylethanolamine were then added, the mixture was
homogenized for 30 minutes and dispersing was carried out with
1,595 g of water at approx. 60.degree. C. over a period of 2 hours.
The methyl ethyl ketone was then distilled off in vacuo. A
copolymer dispersion having the following data was obtained:
TABLE-US-00008 OH content (calculated for solids) 3.7% Acid number
(solids) 12.5 mg of KOH/g Solids content 44.5% Viscosity 560
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 150 nm Cosolvent 7.2 wt.
%
Example 8
[0197] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 126.5 g of styrene, 90.4 g of 2-ethylhexyl acrylate
and 12.5 g of CoatOSil.RTM. 1706 was metered in during the course
of 3.5 hours, and immediately thereafter a mixture 3) of 63.8 g of
styrene, 90 g of hydroxyethyl acrylate, 50 g of butyl acrylate and
28.7 g of methacrylic acid was metered in during the course of 1.5
hours. In parallel with mixture 2) and 3), a mixture 4) of 14.5 g
of di-tert-butyl peroxide in 14.5 g of Dowanol.RTM. PnB was metered
in over a period of 5 hours. A mixture 5) of 4 g of di-tert-butyl
peroxide in 4 g of Dowanol.RTM. PnB was then metered in over a
period of 1 hour. The mixture was then cooled to 70.degree. C. 872
g of a 36 wt. % strength colloidal dispersion of silicon dioxide in
methyl ethyl ketone (Organosilicasol.RTM. MEK-ST, Nissan Chem. Am.
Corp.) were introduced into this melt. 31.2 g of
N,N-dimethylethanolamine were then added, the mixture was
homogenized for 30 minutes and dispersing was carried out with
1,985 g of water at approx. 60.degree. C. over a period of 2 hours.
The methyl ethyl ketone was then distilled off in vacuo. A
copolymer dispersion having the following data was obtained:
TABLE-US-00009 OH content (calculated for solids) 3.6% Acid number
(solids) 12.5 mg of KOH/g Solids content 41.5% Viscosity 560
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 150 nm Cosolvent 6.3 wt.
%
Example 9
[0198] 220 g of Dowanol.RTM. PnB were initially introduced into a 5
l reaction vessel with a stirring, cooling and heating device and
were heated up to 138.degree. C. A mixture 1) of 4 g of
di-tert-butyl peroxide in 4 g of Dowanol.RTM. PnB was added
dropwise at this temperature in the course of 30 minutes.
Immediately thereafter, a mixture 2) of 298.3 g of i-bornyl
methacrylate, 292.0 g of hydroxyethyl acrylate, 169.8 g of butyl
methacrylate, 76.5 g of styrene, 90.4 g of 2-ethylhexyl acrylate
and 62.5 g of CoatOSil.RTM. 1706 was metered in during the course
of 3.5 hours, and immediately thereafter a mixture 3) of 63.8 g of
styrene, 90 g of hydroxyethyl acrylate, 50 g of butyl acrylate and
28.7 g of methacrylic acid was metered in during the course of 1.5
hours. In parallel with mixture 2) and 3), a mixture 4) of 14.5 g
of di-tert-butyl peroxide in 14.5 g of Dowanol.RTM. PnB was metered
in over a period of 5 hours. A mixture 5) of 4 g of di-tert-butyl
peroxide in 4 g of Dowanol.RTM. PnB was then metered in over a
period of 1 hour. The mixture was then cooled to 70.degree. C.
1,308 g of a 36 wt. % strength colloidal dispersion of silicon
dioxide in methyl ethyl ketone (Organosilicasol.RTM. MEK-ST, Nissan
Chem. Am. Corp.) were introduced into this melt. 31.2 g of
N,N-dimethylethanolamine were then added, the mixture was
homogenized for 30 minutes and dispersing was carried out with
2,180 g of water at approx. 60.degree. C. over a period of 2 hours.
The methyl ethyl ketone was then distilled off in vacuo. A
copolymer dispersion having the following data was obtained:
TABLE-US-00010 OH content (calculated for solids) 3.2% Acid number
(solids) 11.5 mg of KOH/g Solids content 41.5% Viscosity 430
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 155 nm Cosolvent 5.8 wt.
%
Example 10
15 wt. % of SiO.sub.2 Nanoparticles, Aqueous SiO.sub.2 Sol
[0199] 4,000 g of aqueous dispersion according to Comparison
Example 5 were mixed with 705 g of Bindzil.RTM. CC40 in a 5 l
reaction vessel with a stirring, cooling and heating device. A
homogeneous aqueous dispersion resulted.
TABLE-US-00011 OH content (calculated for solids) 3.6% Acid number
(solids) 12.5 mg of KOH/g Solids content 40.2% Viscosity 430
mPas.sub.23 .degree. C. pH (10% strength in water) 8.4 Degree of
neutralization 105% Average particle size 155 nm Cosolvent 6.3 wt.
%
Example 11
Crosslinking Agent
[0200] 750 g of Rhodiasolv.RTM. RPDE were initially introduced into
a 5 l reaction vessel with a stirring, cooling and heating device.
2,975 g of Desmodur.RTM. XP 2410 and 1275 g of Bayhydur.RTM. XP
2655 were added and the components were mixed homogeneously.
[0201] The resulting crosslinking agent had an isocyanate content
of 19.3%.
Use Examples 12
[0202] The individual components of component A and B were mixed in
the stated ratios of amounts.
[0203] The mixed 2C water-based clear lacquer was applied by means
of a commercially available spray gun to an aluminium sheet which
had been precoated with an aqueous filler layer and an aqueous
black base lacquer layer conventional for automobile first
lacquering.
[0204] After the application, the sheets were dried in air for 5
minutes at room temperature and 10 minutes at 80.degree. C., and
thereafter dried at 130.degree. C. for 30 minutes. The dry layer
thickness of the clear lacquer was approx. 40 .mu.m.
TABLE-US-00012 A B C D E F G H I K pt. by pt. by pt. by pt. by pt.
by pt. by pt. by pt. by pt. by pt. by Example 12 wt. wt. wt. wt.
wt. wt. wt. wt. wt. wt. Component A Example 1 500 Example 2 500
Example 3 500 Example 4 500 Example 5 500 Example 6 500 Example 7
500 Example 8 500 Example 9 500 Example 10 500 Byk .RTM. 345 4 4 4
4 4 4 4 4 4 4 Byk .RTM. 325 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25
1.25 1.25 Water 74.5 61.8 50.5 89.2 75.1 50.9 89.7 34.1 21.7 27.2
Component B Example 11 149.1 132.7 118.8 115.4 149.1 118.7 115.3
96.9 80.7 98.9 Results A B C D E F G H I K Content of 0.0 3.6 6.9
10.5 0.0 6.9 10.5 13.6 19.7 10.0 nano-SiO.sub.2 based on solids
(wt. %) Gloss/haze 90/10 90/15 88/35 83/113 91/9 90/11 91/10 90/15
90/18 90/17 Visual slight significant severe clear clear clear
clear clear slight evaluation clear haze haze haze haze of haze Dry
scratch 18 19 21 20 19 30 43 59 55 91 resistance, 10 double strokes
Residual gloss (rel. %)
Gloss and Haze
[0205] The gloss was measured in accordance with DIN EN ISO 2813.
The higher the gloss measurement value, the better the gloss. The
haze was measured in accordance with DIN EN ISO 13803. The lower
the haze value, the clearer the lacquer.
Scratch Resistance
[0206] Testing of the scratch resistance of the clear lacquers
prepared was carried out in accordance with DIN 55668.
[0207] The relative residual gloss in % reproduces how high the
degree of gloss [20.degree.] is after scratching in accordance with
DIN 5668 compared with the degree of gloss before scratching. The
higher this value, the better the scratch resistance.
[0208] As Examples 12 A to K clearly show, formulations 12 F to K
according to the invention are distinguished by improved scratch
resistance, while retaining the good optical properties, in
particular low haze.
* * * * *