U.S. patent application number 12/669049 was filed with the patent office on 2010-07-29 for nir-inert substrates comprising bis-oxodihydroindolylen-benzodifuranones.
Invention is credited to Paul Brown, Philippe Bugnon, Veronique Hall-Goulle, Thomas Ruch.
Application Number | 20100186891 12/669049 |
Document ID | / |
Family ID | 39149223 |
Filed Date | 2010-07-29 |
United States Patent
Application |
20100186891 |
Kind Code |
A1 |
Ruch; Thomas ; et
al. |
July 29, 2010 |
NIR-INERT SUBSTRATES COMPRISING
BIS-OXODIHYDROINDOLYLEN-BENZODIFURANONES
Abstract
A method for producing infra-red inert substrates, including
moulded polymeric articles, films, fibers and coatings and other
organic and inorganic materials, by incorporating into the
substrate or onto the surface of the substrate an effective amount
of a dispersed bis-oxodihydroindolylen-benzodifuranone colourant.
The thus obtained, also claimed substrates so produced are
reflective and transparent to much of the near infra red radiation
not reflected. There are multiple applications for cases of devices
comprising electronic components, outdoor construction elements,
outdoor furniture, automotive, marine or aerospace parts,
laminates, artificial leather or textile materials, as well as in
polychrome printing processes and optical fibers. The thus obtained
substrates can also be subjected to laser welding. New
bis-oxo-dihydroindolylen-benzodifuranone compounds are also
claimed.
Inventors: |
Ruch; Thomas; (Delemont,
CH) ; Bugnon; Philippe; (Le Mouret, CH) ;
Brown; Paul; (Binzen, DE) ; Hall-Goulle;
Veronique; (Dornach, CH) |
Correspondence
Address: |
BASF Performance Products LLC;Patent Department
540 White Plains Road, P.O. Box 2005
Tarrytown
NY
10591
US
|
Family ID: |
39149223 |
Appl. No.: |
12/669049 |
Filed: |
July 16, 2008 |
PCT Filed: |
July 16, 2008 |
PCT NO: |
PCT/EP08/59265 |
371 Date: |
January 14, 2010 |
Current U.S.
Class: |
156/272.8 ;
106/506; 427/256; 428/195.1; 428/323; 428/34.1; 428/411.1; 428/457;
524/94; 548/456 |
Current CPC
Class: |
C08K 5/3417 20130101;
C09B 67/0013 20130101; Y10T 428/25 20150115; C09B 57/00 20130101;
C09D 11/322 20130101; B32B 38/0008 20130101; Y10T 428/1372
20150115; C09D 5/035 20130101; C07D 493/04 20130101; C09D 7/41
20180101; B05D 7/52 20130101; Y10T 428/24802 20150115; B32B 37/04
20130101; C09D 5/028 20130101; Y10T 428/13 20150115; B32B 37/182
20130101; C09D 11/18 20130101; Y10T 428/31504 20150401; C09D 11/037
20130101; Y10T 428/31678 20150401; B05D 5/06 20130101 |
Class at
Publication: |
156/272.8 ;
106/506; 428/323; 428/411.1; 428/457; 428/195.1; 428/34.1; 427/256;
524/94; 548/456 |
International
Class: |
B32B 37/06 20060101
B32B037/06; C08K 5/00 20060101 C08K005/00; B32B 5/16 20060101
B32B005/16; B32B 9/04 20060101 B32B009/04; B32B 15/04 20060101
B32B015/04; B32B 3/10 20060101 B32B003/10; B32B 1/02 20060101
B32B001/02; B05D 5/00 20060101 B05D005/00; C08K 5/3417 20060101
C08K005/3417; C07D 405/14 20060101 C07D405/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2007 |
EP |
07112790.6 |
Claims
1. A method for preparing a near infra red inert organic or
inorganic substrate, which method comprises the incorporation into
the substrate, or the application onto the surface of the
substrate, of a composition containing a
bis-oxodihydroindolylen-benzodifuranone colourant of formula
##STR00008## or an isomer or tautomer thereof, wherein the
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) or isomer or tautomer thereof is in the form of particles
of mean size .ltoreq.0.5 .mu.m or of mean size >0.5 .mu.m and
thickness .gtoreq.0.4 .mu.m which are well dispersed in the
composition, in an amount effective to impart to a reflective
organic or inorganic substrate an infra red reflectance of
.gtoreq.20%, to a transparent organic or inorganic substrate an
infra red transmittance of .gtoreq.30%, or to a semi-transparent
organic or inorganic substrate a combined infra red reflectance and
transmittance of .gtoreq.25%, each at wavelengths from 850 to 1600
nm, in which formulae (Ia) and (Ib) R.sub.1 and R.sub.6 are each
independently of the other H, CH.sub.3, CF.sub.3, F or Cl; R.sub.2,
R.sub.3, R.sub.4, R.sub.6, R.sub.7, R.sub.8, R.sub.9 and R.sub.10
are each independently of all others H, halogen, R.sub.11, COOH,
COOR.sub.11, COO.sup.-, CONH.sub.2, CONHR.sub.11,
CONR.sub.11R.sub.12, CN, OH, OR.sub.11, OOCR.sub.11, OOCNH.sub.2,
OOCNHR.sub.11, OOCNR.sub.11R.sub.12, NO.sub.2, NH.sub.2,
NHR.sub.11, NR.sub.11R.sub.12, NHCOR.sub.12, NR.sub.11COR.sub.12,
N.dbd.CH.sub.2, N.dbd.CHR.sub.11, N.dbd.CR.sub.11R.sub.12, SH,
SR.sub.11, SOR.sub.11, SO.sub.2R.sub.11, SO.sub.3R.sub.11,
SO.sub.3H, SO.sub.3, SO.sub.2NH.sub.2, SO.sub.2NHR.sub.11 or
SO.sub.2NR.sub.11R.sub.12; whereby R.sub.2 and R.sub.3, R.sub.3 and
R.sub.4, R.sub.4 and R.sub.5, R.sub.7 and R.sub.5, R.sub.5 and
R.sub.9, and/or R.sub.9 and R.sub.10 can optionally be linked
together by a direct bond or an O, S, NH or NR.sub.11 bridge;
R.sub.11 and R.sub.12 are each independently of the other
C.sub.1-C.sub.12alkyl, C.sub.1-C.sub.12cycloalkyl,
C.sub.1-C.sub.12alkenyl, C.sub.1-C.sub.12cycloalkenyl or
C.sub.1-C.sub.12alkinyl, each of which is uninterrupted or
interrupted by O, NH, NR.sub.13 and/or S in two or more fragments
each comprising at least 2 C atoms, and each of which is also
unsubstituted or substituted one or more times with COOH,
COOR.sub.13, COO.sup.-, CONH.sub.2, CONHR.sub.13,
CONR.sub.13R.sub.14, CN, O, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NR.sub.13,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3.sup.-,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen; or C.sub.7-C.sub.12aralkyl, C.sub.1-C.sub.11heteroaryl or
C.sub.6-C.sub.12aryl, each of which is unsubstituted or substituted
one or more times with COOH, COOR.sub.13, COO, CONH.sub.2,
CONHR.sub.13, CONR.sub.13R.sub.14, CN, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NO.sub.2,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen; and each R.sub.13 or R.sub.14 is, independently of any
other R.sub.13 or R.sub.14, C.sub.1-C.sub.6alkyl, benzyl or phenyl,
each of which is unsubstituted or substituted one or more times
with COOH, COOR.sub.13, COO.sup.-, CONH.sub.2, CONHR.sub.13,
CONR.sub.13R.sub.14, CN, O, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NR.sub.13,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3.sup.-,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen with the proviso that the total number of atoms in any
substituent of R.sub.13 and R.sub.14 is from 1 to 8; whereby pairs
of substituents selected from the group consisting of all R.sub.13
and R.sub.14 can optionally be linked together by a direct bond or
an O, S, NH or NR.sub.11 bridge so as to form rings.
2. A method according to claim 1, wherein the colourant of formula
(Ia) or (Ib) is incorporated into a thermoplastic, elastomeric,
crosslinked or inherently crosslinked polymer.
3. The method according to claim 1, wherein the
bis-oxodihydroindolylen-benzodifuranone is incorporated into a
coating composition which is applied to the surface of the
substrate.
4. A near infra red inert composition or article comprising an
organic or inorganic substrate and, in an amount effective to
impart to the organic or inorganic substrate an infra red
reflectance of .gtoreq.20%, an infra red transmittance of
.gtoreq.30%, or a combined infra red reflectance and transmittance
of .gtoreq.25%, each at wavelengths from 850 to 1600 nm, a
bis-oxodihydroindolylen-benzodifuranone colourant of formula
##STR00009## or an isomer or tautomer thereof, wherein the
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) or isomer or tautomer thereof is in the form of particles
of mean size .ltoreq.0.5 .mu.m or of mean size >0.5 .mu.m and
thickness .gtoreq.0.4 .mu.m which are well dispersed in the
composition, in which formulae (Ia) and (Ib) R.sub.1 and R.sub.6
are each independently of the other H, CH.sub.3, CF.sub.3, F or Cl;
R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.7, R.sub.8, R.sub.9 and
R.sub.10 are each independently of all others H, halogen, R.sub.11,
COOH, COOR.sub.11, COO, CONH.sub.2, CONHR.sub.11,
CONR.sub.11R.sub.12, CN, OH, OR.sub.11, OOCR.sub.11, OOCNH.sub.2,
OOCNHR.sub.11, OOCNR.sub.11R.sub.12, NO.sub.2, NH.sub.2,
NHR.sub.11, NR.sub.11R.sub.12, NHCOR.sub.12, NR.sub.11COR.sub.12,
N.dbd.CH.sub.2, N.dbd.CHR.sub.11, N.dbd.CR.sub.11R.sub.12, SH,
SR.sub.11, SOR.sub.11, SO.sub.2R.sub.11, SO.sub.3R.sub.11,
SO.sub.3H, SO.sub.3, SO.sub.2NH.sub.2, SO.sub.2NHR.sub.11 or
SO.sub.2NR.sub.11R.sub.12; whereby R.sub.2 and R.sub.3, R.sub.3 and
R.sub.4, R.sub.4 and R.sub.5, R.sub.7 and R.sub.8, R.sub.8 and
R.sub.9, and/or R.sub.9 and R.sub.10 can optionally be linked
together by a direct bond or an O, S, NH or NR.sub.11 bridge;
R.sub.11 and R.sub.12 are each independently of the other
C.sub.1-C.sub.12alkyl, C.sub.1-C.sub.12cycloalkyl,
C.sub.1-C.sub.12alkenyl, C.sub.1-C.sub.12cycloalkenyl or
C.sub.1-C.sub.12alkinyl, each of which is uninterrupted or
interrupted by O, NH, NR.sub.13 and/or S in two or more fragments
each comprising at least 2 C atoms, and each of which is also
unsubstituted or substituted one or more times with COOH,
COOR.sub.13, COO.sup.-, CONH.sub.2, CONHR.sub.13,
CONR.sub.13R.sub.14, CN, O, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NR.sub.13,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen; or C.sub.7-C.sub.12aralkyl, C.sub.1-C.sub.11heteroaryl or
C.sub.6-C.sub.12aryl, each of which is unsubstituted or substituted
one or more times with COOH, COOR.sub.13, COO.sup.-, CONH.sub.2,
CONHR.sub.13, CONR.sub.13R.sub.14, CN, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NO.sub.2,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen; and each R.sub.13 or R.sub.14 is, independently of any
other R.sub.13 or R.sub.14, C.sub.1-C.sub.6alkyl, benzyl or phenyl,
each of which is unsubstituted or substituted one or more times
with COOH, COOR.sub.13, COO.sup.-, CONH.sub.2, CONHR.sub.13,
CONR.sub.13R.sub.14, CN, O, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NR.sub.13,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3.sup.-,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen with the proviso that the total number of atoms in any
substituent of R.sub.13 and R.sub.14 is from 1 to 8; whereby pairs
of substituents selected from the group consisting of all R.sub.13
and R.sub.14 can optionally be linked together by a direct bond or
an O, S, NH or NR.sub.11 bridge so as to form rings.
5. The infra red inert composition of claim 4, wherein the
substrate is a thermoplastic, elastomeric, crosslinked or
inherently crosslinked polymer.
6. The composition of claim 4, which is a coating composition.
7. A multilayer coating comprising a primer coating composition
according to claim 6 comprising a colourant of formulae (Ia) or
(Ib), or an isomer or tautomer thereof and a white pigment in a
weight ratio of from 1:99 to 99:1; a basecoat comprising a black,
colour, metallic or interference pigment; and optionally a clear
topcoat.
8. An article comprising a substrate which is coated with the
composition according to claim 6.
9. An item comprising the composition according to claim 4 on which
there is a mark showing a pattern which is different when viewed or
recorded under sequential irradiation by two electromagnetic waves
of different emission spectra in the range from 400 nm to 2 .mu.m
under the same or different dihedral angles to the surface of the
item, or viewed or recorded under irradiation by electromagnetic
waves of the same emission spectrum in the range from 400 nm to 2
.mu.m under different dihedral angles to the surface of the item,
which mark comprises at least two different colourants, each
colourant being embedded in a wet, dry or cured ink which may be
the same or different for part or all of the colourants, at least
two wet, dry or cured inks preferably reflecting differently under
irradiation by electromagnetic waves of emission spectrum in the
range from 400 nm to 2 .mu.m, characterized in that the mark
comprises an effective amount of a colourant of formula (Ia) or
(Ib) or an isomer or tautomer thereof, in at least one of the wet,
dry or cured inks.
10. A method for identifying an item, characterized in that said
item comprises a mark comprising an effective amount of a colourant
of formula (Ia) or (Ib) according to claim 1, or an isomer or
tautomer thereof wherein said mark is recorded under irradiation by
electromagnetic waves of wavelength from 715 to 2000 nm, and the
mark's image is used for identifying the item.
11. A case for a device comprising electronic components, which
case comprises or is coated with a composition according to claim 4
wherein the colourant of formula (Ia) or (Ib) is applied in
combination with a white, low- or non-NIR-absorbingblack, colour,
metallic or interference pigment, in a weight ratio of from 1:99 to
99:1.
12. An outdoor construction element, outdoor furniture, automotive,
marine or aerospace part, laminate, artificial leather or textile
material which comprises or is coated with a composition according
to claim 4 wherein the colourant of formula (Ia) or (Ib) is applied
in combination with a white, low- or non-NIR-absorbingblack,
colour, metallic or interference pigment, in a weight ratio of from
1:99 to 99:1.
13. A polychrome printing process, wherein the black ink, or one of
the black inks, comprises a bis-oxodihydroindolylen-benzodifuranone
colourant of formula (Ia) or (Ib) according to claim 1, or an
isomer or tautomer thereof.
14. A method for laser welding an article, wherein a
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) according to claim 1, or an isomer or tautomer thereof is
incorporated into a polymeric composition which is in contact with
a surface of a meltable substrate containing a near infra red
absorbing material, then near infra red radiation preferably from a
laser of wavelength in the range from 700 to 2000 nm is passed
through the layer containing the colourant of formula (Ia) or (Ib)
to the underlying substrate generating enough heat at the point of
irradiation to melt together the two materials.
15. A compound of formula (Ia) or (Ib) according to claim 1, or an
isomer or tautomer thereof, with the proviso that the compound is
not the compound of formula ##STR00010##
16. A method according to claim 2, wherein the colourant of formula
(Ia) or (Ib) is incorporated into a polyolefin, polyamide,
polyurethane, polyacrylate, polyacrylamide, polyvinyl alcohol,
polycarbonate, polystyrene, polyester, polyacetal, a natural or
synthetic rubber or a halogenated vinyl polymer.
17. The method according to claim 1, wherein the
bis-oxodihydroindolylen-benzodifuranone is incorporated into a
coating composition which is applied to the surface a
thermoplastic, elastomeric, crosslinked or inherently crosslinked
polymer substrate which is in the form of a film or coating applied
to the surface of a substrate, or in the form of a fiber, sheet or
other moulded or shaped article.
18. The infra red inert composition according to claim 5, wherein
the thermoplastic, elastomeric, crosslinked or inherently
crosslinked polymer is a polyolefin, polyamide, polyurethane,
polyacrylate, polyacrylamide, polyvinyl alcohol, polycarbonate,
polystyrene, polyester, polyacetal, a natural or synthetic rubber
or a halogenated vinyl polymer.
Description
[0001] The invention belongs to a method for producing near
infra-red inert substrates, including moulded polymeric articles,
films, fibers and coatings and other organic and inorganic
materials, by incorporating into the substrate or onto the surface
of the substrate an effective amount of a
bis-oxodihydroindolylen-benzodifuranone colourant. The colourants
of the invention have the added property of being transparent to
much of the near infra-red (NIR) radiation not reflected. Thus,
very little NIR radiation is absorbed by these darkly colored
colourants, further limiting heat build up and allowing for the
production of laser welded articles.
[0002] Materials which possess near infra-red (NIR) reflectance
characteristics have proven to be valuable in many current
applications. Such materials reduce NIR-induced heat buildup and
find use in automotive and marine coatings, containers, colored
plastics such as vinyl sidings, etc. Thermally robust compositions
also find use in inorganic and organic glazing and aerospace,
architectural and other glass and ceramic decorative applications
where reduced heat buildup is desired.
[0003] Other applications which make use of NIR reflective
materials include protective camouflage for military
applications.
[0004] U.S. Pat. No. 6,171,383 and U.S. Pat. No. 6,221,147, both
hereby incorporated in their entirety by reference, disclose IR
reflective bismuth manganese oxide green pigments with improved
heat buildup properties.
[0005] U.S. Pat. No. 6,989,056, hereby incorporated in its entirety
by reference, discloses IR reflective black pigment compositions
containing a halogenated copper phthalocyanine and a
perylenetetracarboxylic acid diimide.
[0006] DE 31 11 650 and DE 33 11 375 disclose greenish, reddish or
bluish black isoindolin colourants having a high IR remission.
[0007] US 2003/0 083 407 discloses polymeric articles comprising
red, violet, blue or brown bismethine benzodifuranone colourants
and teaches away from the isatin-based benzodifuranones of WO00/24
736, which discloses the compound of formula
##STR00001##
(example 12b).
[0008] EP 1 217 044 discloses near infra red reflecting composite
pigments comprising a white pigment coated with a near infra red
transmitting organic pigment, particularly preferred the black
pigment of formula
##STR00002##
[0009] DE 195 40 682 discloses coating compositions for heat
radiation reflecting coatings comprising at least one black
pigment, at least one colour pigment, finely dispersed silicic acid
and optionally white or other pigments, fillers and/or coating
additives. In example 1, Chromofine.RTM. Black A 1103
(Dainichiseika, an azomethine-type pigment of undisclosed
structure, having no Colour Index classification) is used.
[0010] WO 01/32 577 discloses pigmented vitreous materials, amongst
which a glass plate coated with tetraethoxysilane, aqueous nitric
acid and the colourant of formula
##STR00003##
(example 41), which has an absorption maximum at 760-765 nm after
heating to 200.degree. C.
[0011] In spite of the advancements made in the art, there remains
a need for new, stable, IR inert compositions.
[0012] It has surprisingly been found that incorporating
bis-oxodihydroindolylen-benzodifuranone colourants (pigments or
dyes) into plastics or coatings render the plastics or coatings NIR
inert. The colourants of the present invention allow for the
preparation of dark colored (including black, brown and especially
grey, also brighter grey hues), NIR inert substrates.
[0013] As used herein, the term "NIR inert" means the properties of
a material at wavelengths from 750 nm to 2 .mu.m. That is,
electromagnetic radiation at wavelengths from 750 nm to 2 .mu.m is
partially reflected and partially transmitted, and its energy does
not or only poorly accumulate in the substrate. The NIR
characteristics of articles produced according to this invention
are highly advantageous in applications where heat buildup due to
the absorption of NIR radiation is to be minimized or where
detection by NIR sensors is to be minimized.
[0014] The same colourants, which are darkly colored, generally
black or nearly black, are also found to reflect some near
infra-red radiation while being transparent to much of the
non-reflected NIR radiation. Incorporating the colourants into, for
example, a layer which is in contact with a substrate containing a
NIR absorbing material, such as a carbon black pigmented polymer,
allows one to pass NIR radiation, as from a laser, through the
layer containing the pigments of the invention to the underlying
substrate generating enough heat at the point of irradiation to
"laser weld", or melt the two materials together.
[0015] A method is provided for preparing a near infra red inert
organic or inorganic substrate, which method comprises the
incorporation into the substrate, or the application onto the
surface of the substrate, of a composition containing a
bis-oxodihydroindolylen-benzodifuranone colourant of formula
##STR00004##
##STR00005##
or an isomer or tautomer thereof, preferably a pigment of formulae
(Ia) or (Ib) or an isomer or tautomer thereof, wherein the
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) or isomer or tautomer thereof is in the form of particles
of mean size .ltoreq.0.5 .mu.m or of mean size >0.5 .mu.m and
thickness .gtoreq.0.4 .mu.m which are well dispersed in the
composition, in an amount effective to impart to a reflective
organic or inorganic substrate an infra red reflectance of
.gtoreq.20%, to a transparent organic or inorganic substrate an
infra red transmittance of .gtoreq.30%, or to a semi-transparent
organic or inorganic substrate a combined infra red reflectance and
transmittance of .gtoreq.25%, each at wavelengths from 850 to 1600
nm, in which formulae (Ia) and (Ib) R.sub.1 and R.sub.6 are each
independently of the other H, CH.sub.3, CF.sub.3, F or Cl,
preferably H or F, most preferably H; R.sub.2, R.sub.3, R.sub.4,
R.sub.5, R.sub.7, R.sub.8, R.sub.9 and R.sub.10 are each
independently of all others H, halogen, R.sub.11, COOH,
COOR.sub.11, COO.sup.-, CONH.sub.2, CONHR.sub.11,
CONR.sub.11R.sub.12, CN, OH, OR.sub.11, OOCR.sub.11, OOCNH.sub.2,
OOCNHR.sub.11, OOCNR.sub.11R.sub.12, NO.sub.2, NH.sub.2,
NHR.sub.11, NR.sub.11R.sub.12, NHCOR.sub.12, NR.sub.11COR.sub.12,
N.dbd.CH.sub.2, N.dbd.CHR.sub.11, N.dbd.CR.sub.11R.sub.12, SH,
SR.sub.11, SOR.sub.11, SO.sub.2R.sub.11, SO.sub.3R.sub.11,
SO.sub.3H, SO.sub.3.sup.-, SO.sub.2NH.sub.2, SO.sub.2NHR.sub.11 or
SO.sub.2NR.sub.11R.sub.12; whereby R.sub.2 and R.sub.3, R.sub.3 and
R.sub.4, R.sub.4 and R.sub.5, R.sub.7 and R.sub.8, R.sub.8 and
R.sub.9, and/or R.sub.9 and R.sub.10 can optionally be linked
together by a direct bond or an O, S, NH or NR.sub.11 bridge;
[0016] R.sub.11 and R.sub.12 are each independently of the other
C.sub.1-C.sub.12alkyl, C.sub.1-C.sub.12cycloalkyl,
C.sub.1-C.sub.12alkenyl, C.sub.1-C.sub.12cycloalkenyl or
C.sub.1-C.sub.12alkinyl, each of which is uninterrupted or
interrupted by O, NH, NR.sub.13 and/or S in two or more fragments
each comprising at least 2 C atoms, and each of which is also
unsubstituted or substituted one or more times with COOH,
COOR.sub.13, COO.sup.-, CONH.sub.2, CONHR.sub.13,
CONR.sub.13R.sub.14, CN, O, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NR.sub.13,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen;
or C.sub.7-C.sub.12aralkyl, C.sub.1-C.sub.11heteroaryl or
C.sub.6-C.sub.12aryl, each of which is unsubstituted or substituted
one or more times with COOH, COOR.sub.13, COO.sup.-, CONH.sub.2,
CONHR.sub.13, CONR.sub.13R.sub.14, CN, OH, OR.sub.13, OOCR.sub.13,
OOCNH.sub.2, OOCNHR.sub.13, OOCNR.sub.13R.sub.14, NO.sub.2,
NH.sub.2, NHR.sub.13, NR.sub.13R.sub.14, NHCOR.sub.14,
NR.sub.13COR.sub.14, N.dbd.CH.sub.2, N.dbd.CHR.sub.13,
N.dbd.CR.sub.13R.sub.14, SH, SR.sub.13, SOR.sub.13,
SO.sub.2R.sub.13, SO.sub.3R.sub.13, SO.sub.3H, SO.sub.3.sup.-,
SO.sub.2NH.sub.2, SO.sub.2NHR.sub.13, SO.sub.2NR.sub.13R.sub.14 or
halogen; and each R.sub.13 or R.sub.14 is, independently of any
other R.sub.13 or R.sub.14, C.sub.1-C.sub.6alkyl, benzyl or phenyl,
each of which is unsubstituted or substituted one or more times
with substituents as defined in the preceding paragraph, with the
proviso that the total number of atoms in any substituent of
R.sub.13 and R.sub.14 is from 1 to 8; whereby pairs of substituents
selected from the group consisting of all R.sub.13 and R.sub.14 can
optionally be linked together by a direct bond or an O, S, NH or
NR.sub.11 bridge so as to form rings.
[0017] Generally, R.sub.13 and R.sub.14 forming a ring are bound to
the same atom, such as in NR.sub.13R.sub.14 or CR.sub.13R.sub.14.
However, it is also possible R.sub.13 and/or R.sub.14 which are
separated by 2 or more atoms to be linked together, thus forming
larger rings.
[0018] When the compound of formula (Ia) or (Ib) is anionic, its
charge may be compensated by any known suitable cation, for example
a metallic, organic, inorganic or metal organic cation, such as
preferably an alkali, earth alkali or transition metal, ammonium,
primary ammonium, secondary ammonium, ternary ammonium, quaternary
ammonium or an organic metal complex.
[0019] The mean size (to be calculated by particle weight) can
easily be determined for example by electron microscopy or
Joyce-Lobl centrifugation (such as described in EP application 07
122 749.0). The particle size distribution is most adequately
determined directly from the dispersion of the colourant in a
solvent and/or binder, avoiding deagglomeration of eventual
remaining agglomerates by using mild conditions.
[0020] The inorganic or organic substrate may be, for example, a
naturally occurring polymer or a synthetic polymer, for example a
thermoplastic, elastomeric, inherently crosslinked or crosslinked
polymer. For example, a method which comprises incorporating into a
thermoplastic, elastomeric, crosslinked or inherently crosslinked
polymer an amount of a deagglomerated
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) is effective to impart to the thermoplastic, elastomeric,
crosslinked or inherently crosslinked polymer an infra red
reflectance of .gtoreq.20%, an infra red transmittance of
.gtoreq.30%, or a combined infra red reflectance and transmittance
of .gtoreq.25%, each at wavelengths from 850 to 1600 nm.
Preferably, the infra red reflectance is .gtoreq.25%, the infra red
transmittance is .gtoreq.40%, or the combined infra red reflectance
and transmittance is .gtoreq.30%, each at wavelengths from 850 to
1600 nm. Most preferred, the infra red reflectance is .gtoreq.30%,
the infra red transmittance is .gtoreq.50%, or the combined infra
red reflectance and transmittance is .gtoreq.40%, each at
wavelengths from 850 to 1600 nm.
[0021] The colourants of formula (Ia) or (Ib) are both reflective
and transparent, however the ratio of reflectance and transmittance
depends on their particle size. The reflectance (including
diffracted reflectance) is much more significant with large
particles, such as those having a thickness of .gtoreq.0.4 .mu.m,
while transmittance is preponderant in the case of tiny particles,
such as those having a size of from 0.01 to 0.3 .mu.m, as well as
in the case of dyes which dissolve into the substrate.
[0022] The instant colourants of formula (Ia) or (Ib) are normally
obtained from the synthesis in the form of very large agglomerates
and aggregates of unattractive dark colours and are highly
difficult to disperse, such as the violet powder obtained according
to example 12b of WO00/24 736. However, it has been found that
these crude powders can easily be transformed into suitable
colourants just by wet-milling them with milling aids in the
presence of a solvent, preferably an alcohol, amide, ester, ether
or ketone, thus obtaining particles of mean size .ltoreq.0.5 .mu.m,
preferably from 0.01 to 0.3 .mu.m, which show surprisingly very
attractive black hues similar to carbon black. Wet-milling can for
example be performed in an attritor, such as a Dyno.RTM. or
Netzsch.RTM. mill, Skandex.RTM. paint shaker or the like, for
example using glass or ceramics (e.g. zirconia) pearls of size
preferably from 0.1 to 3.0 mm, in particular from 0.5 to 1.0 mm.
The amount of alcohol, amide, ester, ether or ketone is adequately
from 0.1 to 1000 parts per part of colourant, preferably from 1 to
10 parts per part of colourant.
[0023] The particles of size .ltoreq.0.5 .mu.m, preferably from
0.01 to 0.3 .mu.m, can further be recrystallized in a polar
solvent, preferably a neutral, polar liquid having a dipole moment
.mu. it of 2.8-6.010.sup.-18 esu, until large particles having a
thickness of .gtoreq.0.4 .mu.m are obtained. Usually, this is done
at high temperature, for example from 60 to 150.degree. C.,
optionally under pressure especially above the solvent's boiling
point. If desired, wet-milling and recrystallisation can be
performed simultaneously, in which case it is adequate to use mild
(low-shear, low-speed) wet-milling conditions towards the end of
the process if large particles are desired.
[0024] Adequate solvents for wet-milling and/or recrystallisation
are well-known in the art, solvents disclosed for example in EP 0
774 494, EP 0 934 364 and WO 02/068 541 being specifically
incorporated herein by reference.
R.sub.2, R.sub.4, R.sub.5, R.sub.7, R.sub.9, and R.sub.10 are
preferably H, F or Cl, especially H, R.sub.3 and R.sub.8 are
preferably H, NO.sub.2, OCH.sub.3, OC.sub.2H.sub.5, Br, Cl,
CH.sub.3, C.sub.2H.sub.5, N(CH.sub.3).sub.2,
N(CH.sub.3)(C.sub.2H.sub.5), N(C.sub.2H.sub.5).sub.2,
.alpha.-naphthyl, .beta.-naphthyl or SO.sub.3.sup.-. Preferably,
R.sub.1 is identical to R.sub.6, R.sub.2 is identical to R.sub.7,
R.sub.3 is identical to R.sub.8, R.sub.4 is identical to R.sub.9,
and/or R.sub.5 is identical to R.sub.10.
[0025] C.sub.1-C.sub.12Alkyl is, for example, methyl, ethyl,
n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl,
2-methyl-butyl, n-pentyl, 2-pentyl, 3-pentyl, 2,2-dimethylpropyl,
n-hexyl, heptyl, n-octyl, 1,1,3,3-tetramethylbutyl, 2-ethylhexyl,
nonyl, decyl, undecyl or dodecyl.
[0026] C.sub.3-C.sub.12Cycloalkyl is, for example, cyclopropyl,
cyclopropyl-methyl, cyclobutyl, cyclopentyl, cyclohexyl,
cyclohexyl-methyl, trimethylcyclohexyl, thujyl, norbornyl, bornyl,
norcaryl, caryl, menthyl, norpinyl, pinyl, 1-adamantyl or
2-adamantyl.
[0027] C.sub.2-C.sub.12Alkenyl is, for example, vinyl, allyl,
2-propen-2-yl, 2-buten-1-yl, 3-buten-1-yl, 1,3-butadien-2-yl,
2-penten-1-yl, 3-penten-2-yl, 2-methyl-1-buten-3-yl,
2-methyl-3-buten-2-yl, 3-methyl-2-buten-1-yl, 1,4-pentadien-3-yl,
or any desired isomer of hexenyl, octenyl, nonenyl, decenyl or
dodecenyl.
[0028] C.sub.3-C.sub.12Cycloalkenyl is, for example,
2-cyclobuten-1-yl, 2-cyclopenten-1-yl, 2-cyclohexen-1-yl,
3-cyclohexen-1-yl, 2,4-cyclohexadien-1-yl, 1-p-menthen-8-yl,
4(10)-thujen-10-yl, 2-norbornen-1-yl, 2,5-norbornadien-1-yl,
7,7-dimethyl-2,4-norcaradien-3-yl or camphenyl.
[0029] C.sub.2-C.sub.12Alkinyl is, for example, 1-propin-3-yl,
1-butin-4-yl, 1-pentin-5-yl, 2-methyl-3-butin-2-yl,
1,4-pentadiin-3-yl, 1,3-pentadiin-5-yl, 1-hexin-6-yl,
cis-3-methyl-2-penten-4-in-1-yl, trans-3-methyl-2-penten-4-in-1-yl,
1,3-hexadiin-5-yl, 1-octin-8-yl, 1-nonin-9-yl, 1-decin-10-yl or
1-dodecin-12-yl.
[0030] C.sub.7-C.sub.12Aralkyl is, for example, benzyl,
2-benzyl-2-propyl, 13-phenyl-ethyl, 9-fluorenyl,
.alpha.,.alpha.-dimethylbenzyl, w-phenyl-butyl, w-phenyl-pentyl or
w-phenyl-hexyl. When C.sub.7-C.sub.12aralkyl is substituted, either
the alkyl moiety or the aryl moiety of the aralkyl group can be
substituted.
[0031] C.sub.6-C.sub.12Aryl is, for example, phenyl, naphthyl or
1-biphenyl.
[0032] Halogen is for example F, Cl, Br or J, preferably F on alkyl
and Cl or Br on aryl.
[0033] C.sub.1-C.sub.11Heteroaryl is an unsaturated or aromatic
radical having 4n+2 conjugated .pi.-electrons, for example
2-thienyl, 2-furyl, 1-pyrazolyl, 2-pyridyl, 2-thiazolyl,
2-oxazolyl, 2-imidazolyl, isothiazolyl, triazolyl, tetrazolyl or
any other ring system consisting of thiophene, furan, thiazole,
oxazole, imidazole, isothiazole, thiadiazole, triazole, pyridine,
pyrazine, pyrimidine, pyridazine and benzene rings and
unsubstituted or substituted by from 1 to 6 ethyl substituents.
[0034] Heterocyclic groups are for example
##STR00006##
[0035] Heterocyclic groups may also be formed by linking adjacent
substituents of aryl, for example
##STR00007##
[0036] The composition containing the
bis-oxodihydroindolylen-benzodifuranone colourant may be composed
entirely of the pigment or dye, or of a mixture or solid solution
of two or more thereof (especially from 2 to 10), or other
materials as disclosed herein may also be present. Pigments and
mixtures thereof are much preferred to dyes.
[0037] The bis-oxodihydroindolylen-benzodifuranone colourants of
the present invention are prepared for example according or in
analogy to the method disclosed in example 12b of WO00/24 736.
[0038] As used herein, the term "NIR inert" means the properties of
a material at wavelengths from 750 nm to 2 .mu.m. That is,
electromagnetic radiation at wavelengths from 750 nm to 2 .mu.m is
reflected and/or transmitted. Substrates containing the present
colourants, or articles coated with compositions containing the
present colourants, typically have a near infra red reflectance of
.gtoreq.20%, a near infra red transmittance of .gtoreq.30%, or a
combined near infra red reflectance and transmittance of
.gtoreq.25%, each at wavelengths from 850 to 1600 nm, in particular
from 1000 to 1200 nm.
[0039] The instant compositions and substrates have the highly
surprising property to show a low chroma in the visible light range
(400-700 nm), preferably a saturation C* of .ltoreq.10, more
preferably .ltoreq.5, most preferably .ltoreq.3. This enables to
prepare superior black shades, similar to carbon black. This is not
the case of known organic black colourants. Of course, it is also
possible to use the colourants of formulae (Ia) or (Ib) in
combination with white, black, colour, metallic or interference
pigments, providing very interesting dark hues, especially grey
shades, which are not obtainable by using known organic black
colourants.
[0040] A particularly preferred embodiment is the use of the
colourants of formulae (Ia) or (Ib) in primers, preferably grey
primers. The primers of the invention comprise the colourants of
formulae (Ia) or (Ib) and at least one white pigment adequately in
a weight ratio of from 1:99 to 99:1, especially from 1:95 to 95:1.
Suitable white pigments are listed in the Colour Index.
[0041] The grey primers of the invention preferably have a low
saturation as defined above, with the additional advantage that
such primer leads to a very significant lower temperature when used
in combination with a basecoat comprising a low- or
non-NIR-absorbing black, colour, metallic or interference pigment.
Their lightness value L* is not essential, it can for example vary
from about 10-20 (blackish to dark grey) over 40-60 (middle grey)
up to 70-90 (very light grey) depending on the requirements for a
particular purpose. The basecoat is preferably applied in 1, 2 or 3
layers directly on the primer coating and recovered by a topcoat.
Preferably, this may be done by the so-called wet-on-wet process.
Optionally, one or more intermediate coatings may be applied
between the primer coating, the basecoat and the topcoat.
[0042] Hence, the invention also pertains to a multilayer coating
comprising [0043] a primer coating comprising a colourant of
formulae (Ia) or (Ib), or an isomer or tautomer thereof, preferably
a pigment of formulae (Ia) or (Ib) or an isomer or tautomer
thereof, and a white pigment in a weight ratio of from 1:99 to
99:1, especially from 1:95 to 95:1; [0044] a basecoat comprising a
black, colour, metallic or interference pigment; and [0045]
optionally a clear topcoat.
[0046] Such multilayer coatings are particularly advantageous for
automotive bodies. When the basecoat comprises a black pigment,
then such black pigment should adequately be free of carbon black
and transmit or reflect infra red light. Preferably, such black
pigment is or comprises a colourant of formulae (Ia) or (Ib),
too.
[0047] These reflectance and transmittance characteristics are
highly advantageous in applications where heat buildup due to the
absorption of near infra red radiation is to be minimized and where
detection by IR sensors is to be minimized. Particularly
advantageously, the instant colourant of formula (Ia) or (Ib) is
applied into or onto cases of devices comprising electronic
components, such as laptop computers, mobile phones, walkmans or
MP3 players, radio equipment, TV receivers, electronic cameras,
measuring equipments such as GPS receivers, road, aerospace or
other radars, telemeters, clinometers or theodolites, remote or
radio controls or further electronic equipment, vehicle dashboards
or automotive bodies, especially front hoods covering
electronically controlled engines, air conditioners, brakes and
sophisticated road-holding controls, such as ABS or EPS. An
additional advantage in electronic applications is the low
conductivity of materials coloured with instant colourants of
formula (Ia) or (Ib).
[0048] Also advantageously, the instant colourant of formula (Ia)
or (Ib) is applied into outdoor construction elements (building
materials), such as roof and wall tiles, sidings, door and window
frames, profiles, architectural glazing, pipes, roller or Venetian
blinds, automotive, marine or aerospace parts including seats and
bodies, outdoor furniture such as garden chairs and tables, or
laminates on such items, artificial leather or textile materials,
including in particular automotive seats as well as in yarns and
fabrics of all kinds (optionally further transformed into rope,
nets, awnings, felt, velvet, synthetic fur and the like), such as
ceremonial or traditional dresses and other clothing (for example
Tudor bonnets, square academic caps, Guardian velvet jackets, abbot
hats, chadors, cassocks, shtreimels, Shinto eboshi hats and the
like), or greenhouse foils, thus decreasing the deformation and
aging and increasing the lifetime of such items, while increasing
the comfort of use and saving energy for air conditioning. The
instant low-heating materials are also much useful in camouflage
applications and leisure, sports or military equipment.
[0049] The advantages in thermal heating are particularly amazing
when the instant colourant of formula (Ia) or (Ib) is applied in
combination with a white, low- or non-NIR-absorbingblack, colour,
metallic or interference pigment, for example in a weight ratio of
from 1:99 to 99:1, especially from 1:95 to 95:1.
[0050] The properties of the instant colourants of formula (Ia) or
(Ib) also enables to use them for optical fibers and items in
contact with them.
[0051] In a further advantageous application, especially in
printing inks, the instant colourant of formula (Ia) or (Ib) is
applied in combination with a compound absorbing in the infra-red
range from 750 nm to 2 .mu.m, for example in a weight ratio of from
1:99 to 99:1, especially from 1:95 to 95:1. Especially useful, the
instant colourant of formula (Ia) or (Ib) is printed above the
compound absorbing in the infra-red range from 750 nm to 2 .mu.m in
a polychrome printing process, such as screen, offset,
lithographic, flexographic, gravure or ink-jet printing processes
(the details of which are well-known to the skilled artisan), onto
a substrate comprising a reflective pigment, such as a white,
colour, metallic or interference pigment. In this case, the
reflectance of the substrate areas not printed with near infra red
absorbing compound through the layer comprising the instant
colourant of formula (Ia) or (Ib) is excellent, enabling
identification of patterns of the near infra red absorbing compound
which are invisible under daylight.
[0052] It has also been found that the instant colourant of formula
(Ia) or (Ib) provides a significant improvement of the contrast
when used in combination with effect pigments, in particular
multi-layered interference pigments, including effect pigments
which show a lightness or goniochromatic flop effect in the infra
red.
[0053] Hence, the instant colourant of formula (Ia) or (Ib) provide
excellent means to manufacture security or identification elements
on an object by printing, especially polychrome printing, or also
to calibrate printers or other devices.
[0054] For polychrome printing, the instant colourant of formula
(Ia) or (Ib) is preferably incorporated into the black ink. If more
than one black ink is printed, the instant colourant of formula
(Ia) or (Ib) is preferably incorporated into the last printed black
ink. Preferably, the near infra red absorbing compound is
substantially colourless, so that a NIR absorbing pattern can be
printed onto the substrate without taking account of the image to
be printed on top of it, or a coloured or black NIR absorbing
compound may be used, for example carbon black, in which case the
NIR absorbing pattern is printed on an area of the substrate fully
to be recovered by the black ink comprising the instant colourant
of formula (Ia) or (Ib).
[0055] Accordingly, the invention also relates to an item on which
there is a mark showing a pattern which is different when viewed or
recorded under sequential irradiation by two electromagnetic waves
of different emission spectra in the range from 400 nm to 2 .mu.m
under the same or different dihedral angles to the surface of the
item, or viewed or recorded under irradiation by electromagnetic
waves of the same emission spectrum in the range from 400 nm to 2
.mu.m under different dihedral angles to the surface of the item,
which mark comprises at least two different colourants, preferably
2, 3, 4, 5, 6, 7, 8, 9, 10 or from 11 to 25 colourants, each
colourant being embedded in a wet, dry or cured ink which may be
the same or different for part or all of the colourants, at least
two wet, dry or cured inks preferably reflecting differently under
irradiation by electromagnetic waves of emission spectrum in the
range from 400 nm to 2 .mu.m, characterized in that the mark
comprises an effective amount of a colourant of formula (Ia) or
(Ib), or an isomer or tautomer thereof, preferably a pigment of
formulae (Ia) or (Ib) or an isomer or tautomer thereof, in at least
one of the wet, dry or cured inks.
[0056] Preferably, the mark comprises a pattern comprising an
infrared absorber, in addition to a different pattern comprising
the instant colourant of formula (Ia) or (Ib). Infrared absorbers
adequate to form well identifiable pattern are any substances
having an .epsilon. value of about .gtoreq.5000
lmol.sup.-1cm.sup.-1 at a wavelength from 715 to 2000 nm in the ink
vehicle. Such infrared absorbers are well-known in the art, their
chemical structure not being relevant for performing the
invention.
[0057] The instant inks comprise adequately a binder and if desired
a solvent and/or a curable compound as usual in the art, each of
which components is usually a mixture of different compounds of the
same or of different chemical classes.
[0058] The two electromagnetic waves of different spectra differ
adequately when the ratio of the two quotients of the emitted
energy of the first electromagnetic wave divided by the emitted
energy of the second electromagnetic wave at two different
wavelengths in the range from 400 nm to 2 .mu.m is at least 3:2,
preferably 10:1.
[0059] The application is performed preferably by printing, but it
is also possible to apply marks by other means, such as by hand,
using sequentially differently pigmented markers, for example with
fountain, felt or ballpoint pens.
[0060] There may of course be multiple, identical or different
marks on an item, enabling to produce both security and decorative
marks, which might also be combined on the same item. The item is
any object, for example but in no way restricted to a paper,
cardboard or polymeric sheet, including bags and labels, a cap,
seal, container of any type, including boxes, casings, or objects
such as automotive and other parts, consumables such as inkjet and
toner cartridges, magnetic tapes or computer readable disks such as
CD-R, CD-RW, DVD.+-.R or Blu-Ray.RTM. or similar disks.
[0061] The mark may in particular be printed on a security item
such as but not restricted to identity, bank, credit or company
cards, checks, banknotes, driving licenses or any other badges,
pass or permits. Counterfeiting security items comprising the
instant colourants of formula (Ia) or (Ib) becomes much more
difficult for reasons evident to a person skilled in the art but
which should of course not be disclosed herein to potential
counterfeiters.
[0062] The marks may optionally be designed to be recognized
automatically. In particular, this applies to bar or mosaic codes
which may be hidden on an apparently plain black area. The mark is
usually applied on only part of the item, for example from 0.1 to
99.9% of the item's surface, but it may also be applied uniformly
on the whole item for solely decorative purposes.
[0063] The invention thus also provides a method for identifying an
item, characterized in that said item comprises a mark comprising
an effective amount of a colourant of formula (Ia) or (Ib), or an
isomer or tautomer thereof, preferably a pigment of formulae (Ia)
or (Ib) or an isomer or tautomer thereof, wherein said mark is
recorded under irradiation by electromagnetic waves of wavelength
from 715 to 2000 nm, and the mark's image is used for identifying
the item.
[0064] Preferably, the mark's image is not apparent or different
under irradiation by visible light (400-700 nm). The mark's image
under infra red may be processed in usual manner visually or
instrumentally and optionally converted into a visible image.
[0065] Also typically, the colourant of formula (Ia) or (Ib) is
incorporated into a composition comprising a thermoplastic,
thermoset, elastomeric, inherently crosslinked or crosslinked
polymer. The polymer may be, for example, in the form of a film,
sheet, injection-moulded article, extruded workpiece, fiber,
laminate, felt or woven fabric. The polymer may also be part of a
coating composition.
[0066] The dispersible colourant of formula (Ia) or (Ib) is either
incorporated directly into the substrate, or applied to the surface
of the substrate.
[0067] When applied to the surface of a substrate, the colourant of
formula (Ia) or (Ib) may be part of a coating composition. The
coating can comprise any coating system, or even a preformed film,
which both adheres to the substrate and is compatible with the
colourant of formula (Ia) or (Ib), for example, automotive
coatings, marine coatings, paints, inks, laminates, receiving
layers for printing applications, or other protective or decorative
coatings including coatings or films used in glazing applications.
The colourant may also be part of a fabric treatment of formula
(Ia) or (Ib).
[0068] Examples of thermoplastic, thermoset, elastomeric,
inherently crosslinked or crosslinked polymers into which the
colourants of the present invention may be incorporated into or
coated onto are listed below. [0069] 1. Polymers of mono- and
di-olefins, for example polypropylene, polyisobutylene,
polybutene-1, poly-4-methylpentene-1, polyisoprene or polybutadiene
and also polymerisates of cyclo-olefins, for example of
cyclopentene or norbornene; and also polyethylene (which may
optionally be crosslinked), for example high density polyethylene
(HDPE), high density polyethylene of high molecular weight
(HDPE-HMW), high density polyethylene of ultra-high molecular
weight (HDPE-UHMW), medium density polyethylene (MDPE), low density
polyethylene (LDPE), and linear low density polyethylene (LLDPE),
(VLDPE) and (ULDPE).
[0070] Polyolefins, that is to say polymers of mono-olefins, as
mentioned by way of example in the preceding paragraph, especially
polyethylene and polypropylene, can be prepared by various
processes, especially by the following methods: [0071] a) by free
radical polymerisation (usually at high pressure and high
temperature); [0072] b) by means of a catalyst, the catalyst
usually containing one or more metals of group IVb, Vb, VIb or
VIII. Those metals generally have one or more ligands, such as
oxides, halides, alcoholates, esters, ethers, amines, alkyls,
alkenyls and/or aryls, which may be either .pi.- or
.sigma.-coordinated. Such metal complexes may be free or fixed to
carriers, for example to activated magnesium chloride,
titanium(III) chloride, aluminium oxide or silicon oxide. Such
catalysts may be soluble or insoluble in the polymerisation medium.
The catalysts can be active as such in the polymerisation or
further activators may be used, for example metal alkyls, metal
hydrides, metal alkyl halides, metal alkyl oxides or metal alkyl
oxanes, the metals being elements of group(s) Ia, IIa and/or IIIa.
The activators may have been modified, for example, with further
ester, ether, amine or silyl ether groups. [0073] 2. Mixtures of
the polymers mentioned under 1.), for example mixtures of
polypropylene with polyisobutylene, polypropylene with polyethylene
(for example PP/HDPE, PP/LDPE) and mixtures of different types of
polyethylene (for example LDPE/HDPE). [0074] 3. Copolymers of mono-
and di-olefins with one another or with other vinyl monomers, for
example ethylene/propylene copolymers, linear low density
polyethylene (LLDPE) and mixtures thereof with low density
polyethylene (LDPE), propylene/butene-1 copolymers,
propylene/isobutylene copolymers, ethylene/butene-1 copolymers,
ethylene/hexene copolymers, ethylene/methylpentene copolymers,
ethylene/heptene copolymers, ethylene/octene copolymers,
propylene/butadiene copolymers, isobutylene/isoprene copolymers,
ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylate
copolymers, ethylene/vinyl acetate copolymers and copolymers
thereof with carbon monoxide, or ethylene/acrylic acid copolymers
and salts thereof (ionomers), and also terpolymers of ethylene with
propylene and a diene, such as hexadiene, dicyclopentadiene or
ethylidenenorbornene; and also mixtures of such copolymers with one
another or with polymers mentioned under 1.), for example
polypropylene-ethylene/propylene copolymers, LDPE-ethylene/vinyl
acetate copolymers, LDPE-ethylene/acrylic acid copolymers,
LLDPE-ethylene/vinyl acetate copolymers, LLDPE-ethylene/acrylic
acid copolymers and alternately or randomly structured
polyalkylene-carbon monoxide copolymers and mixtures thereof with
other polymers, for example polyamides. [0075] 4. Hydrocarbon
resins (for example C.sub.5-C.sub.9) including hydrogenated
modifications thereof (for example tackifier resins) and mixtures
of polyalkylenes and starch. [0076] 5. Polystyrene,
poly(p-methylstyrene), poly(.alpha.-methylstyrene). [0077] 6.
Copolymers of styrene or .alpha.-methylstyrene with dienes or
acrylic derivatives, for example styrene/butadiene,
styrene/acrylonitrile, styrene/alkyl methacrylate,
styrene/butadiene/alkyl acrylate and methacrylate, styrene/maleic
anhydride, styrene/acrylonitrile/methyl acrylate;
high-impact-strength mixtures consisting of styrene copolymers and
another polymer, for example a polyacrylate, a diene polymer or an
ethylene/propylene/diene terpolymer; and also block copolymers of
styrene, for example styrene/butadiene/styrene,
styrene/isoprene/styrene, styrene/ethylene-butylene/styrene or
styrene/ethylene-propylene/styrene. [0078] 7. Graft copolymers of
styrene or .alpha.-methylstyrene, for example styrene on
polybutadiene, styrene on polybutadiene/styrene or
polybutadiene/acrylonitrile copolymers, styrene and acrylonitrile
(or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and
methyl methacrylate on polybutadiene; styrene and maleic anhydride
on polybutadiene; styrene, acrylonitrile and maleic anhydride or
maleic acid imide on polybutadiene; styrene and maleic acid imide
on polybutadiene, styrene and alkyl acrylates or alkyl
methacrylates on polybutadiene, styrene and acrylonitrile on
ethylene/propylene/diene terpolymers, styrene and acrylonitrile on
polyalkyl acrylates or polyalkyl methacrylates, styrene and
acrylonitrile on acrylate/butadiene copolymers, and mixtures
thereof with the copolymers mentioned under 6.), such as those
known, for example, as so-called ABS, MBS, ASA or AES polymers.
[0079] 8. Halogen-containing polymers, for example polychloroprene,
chlorinated rubber, chlorinated and brominated copolymer of
isobutylene/isoprene (halobutyl rubber), chlorinated or
chlorosulfonated polyethylene, copolymers of ethylene and
chlorinated ethylene, epichlorohydrin homo- and co-polymers,
especially polymers of halogen-containing vinyl compounds, for
example polyvinyl chloride, polyvinylidene chloride, polyvinyl
fluoride, polyvinylidene fluoride; and copolymers thereof, such as
vinyl chloride/vinylidene chloride, vinyl chloride/vinyl acetate or
vinylidene chloride/vinyl acetate. [0080] 9. Polymers derived from
.alpha.,.beta.-unsaturated acids and derivatives thereof, such as
polyacrylates and polymethacrylates, or polymethyl methacrylates,
polyacrylamides and polyacrylonitriles impact-resistant-modified
with butyl acrylate. [0081] 10. Copolymers of the monomers
mentioned under 9.) with one another or with other unsaturated
monomers, for example acrylonitrile/butadiene copolymers,
acrylonitrile/alkyl acrylate copolymers, acrylonitrile/alkoxyalkyl
acrylate copolymers, acrylonitrile/vinyl halide copolymers or
acrylonitrile/alkyl methacrylate/butadiene terpolymers. [0082] 11.
Polymers derived from unsaturated alcohols and amines or their acyl
derivatives or acetals, such as polyvinyl alcohol, polyvinyl
acetate, stearate, benzoate or maleate, polyvinylbutyral, polyallyl
phthalate, polyallylmelamine; and the copolymers thereof with
olefins mentioned in 1.). [0083] 12. Homo- and co-polymers of
cyclic ethers, such as polyalkylene glycols, polyethylene oxide,
polypropylene oxide or copolymers thereof with bisglycidyl ethers.
[0084] 13. Polyacetals, such as polyoxymethylene, and also those
polyoxymethylenes which contain comonomers, for example ethylene
oxide; polyacetals modified with thermoplastic polyurethanes,
acrylates or MBS. [0085] 14. Polyphenylene oxides and sulfides and
mixtures thereof with styrene polymers or polyamides. [0086] 15.
Polyurethanes derived from polyethers, polyesters and
polybutadienes having terminal hydroxyl groups on the one hand and
aliphatic or aromatic polyisocyanates on the other hand, and their
initial products. [0087] 16. Polyamides and copolyamides derived
from diamines and dicarboxylic acids and/or from aminocarboxylic
acids or the corresponding lactams, such as polyamide 4, polyamide
6, polyamide 6/6, 6/10, 6/9, 6/12, 4/6, 12/12, polyamide 11,
polyamide 12, aromatic polyamides derived from m-xylene, diamine
and adipic acid; polyamides prepared from hexamethylenediamine and
iso- and/or tere-phthalic acid and optionally an elastomer as
modifier, for example poly-2,4,4-trimethylhexamethylene
terephthalamide or poly-m-phenylene isophthalamide. Block
copolymers of the above-mentioned polyamides with polyolefins,
olefin copolymers, ionomers or chemically bonded or grafted
elastomers; or with polyethers, for example with polyethylene
glycol, polypropylene glycol or polytetramethylene glycol. Also
polyamides or copolyamides modified with EPDM or ABS; and
polyamides condensed during processing ("RIM polyamide systems").
[0088] 17. Polyureas, polyimides, polyamide imides, polyether
imides, polyester imides, polyhydantoins and polybenzimidazoles.
[0089] 18. Polyesters derived from dicarboxylic acids and
dialcohols and/or from hydroxy-carboxylic acids or the
corresponding lactones, such as polyethylene terephthalate,
polybutylene terephthalate, poly-1,4-dimethylolcyclohexane
terephthalate, polyhydroxybenzoates or polycaprolactone, and also
block polyether esters derived from polyethers with hydroxyl
terminal groups; and also polyesters modified with polycarbonates
or MBS. [0090] 19. Polycarbonates and polyester carbonates. [0091]
20. Polysulfones, polyether sulfones and polyether ketones. [0092]
21. Crosslinked polymers derived from aldehydes on the one hand and
phenols, urea or melamine on the other hand, such as
phenol-formaldehyde, urea-formaldehyde and melamine-formaldehyde
resins. [0093] 22. Drying and non-drying alkyd resins. [0094] 23.
Unsaturated polyester resins derived from copolyesters of saturated
and unsaturated dicarboxylic acids with polyhydric alcohols, and
also vinyl compounds as crosslinking agents, and also the
halogen-containing, difficultly combustible modifications thereof.
[0095] 24. Crosslinkable acrylic resins derived from substituted
acrylic esters, e.g. from epoxy acrylates, urethane acrylates or
polyester acrylates. [0096] 25. Alkyd resins, polyester resins and
acrylate resins that are crosslinked with melamine resins, urea
resins, isocyanates, isocyanurates, polyisocyanates or epoxy
resins. [0097] 26. Crosslinked epoxy resins derived from aliphatic,
cycloaliphatic, heterocyclic or aromatic glycidyl compounds, e.g.
products of bisphenol-A diglycidyl ethers, bisphenol-F diglycidyl
ethers, that are crosslinked using customary hardeners, e.g.
anhydrides or amines with or without accelerators. [0098] 27.
Natural polymers, such as cellulose, natural rubber, gelatin, or
polymer-homologously chemically modified derivatives thereof, such
as cellulose acetates, propionates and butyrates, and the cellulose
ethers, such as methyl cellulose; and also colophonium resins and
derivatives. [0099] 28. Mixtures (polyblends) of the
afore-mentioned polymers, for example PP/EPDM, polyamide/EPDM or
ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT,
PVC/CPE, PVC/acrylates, POM/thermoplastic PUR, PC/thermoplastic
PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA 6.6 and copolymers,
PA/HDPE, PA/PP, PA/PPO, PBT/PC/ABS or PBT/PET/PC.
[0100] The thermoplastic, elastomeric, crosslinked or inherently
crosslinked polymer is, for example, a polyolefin, polyamide,
polyurethane, polyacrylate, polyacrylamide, polyvinyl alcohol,
polycarbonate, polystyrene, polyester, polyacetal, a natural or
synthetic rubber or a halogenated vinyl polymer such as PVC. The
polymer may be a co-polymer, a polymer blend or part of a
composite. Polyamide is least preferred because some instant
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) tend to dissolve therein.
[0101] The bis-oxodihydroindolylen-benzodifuranone colourants of
the instant invention may be incorporated into polymer resins
according a variety of known methods, provided they are in a
dispersed or easy dispersible form. For example, the compounds may
be added as an individual component during blending, for example,
dry blending of the resin prior to processing, or the compound may
be added as a blend, master batch, flush, or other concentrate in
another substance prior to processing. The compounds may also be
added during processing steps. Standard process steps for polymer
resins are well known in the literature and include extrusion,
coextrusion, compression moulding, Brabender melt processing, film
formation, injection moulding, blow moulding, roto moulding, other
moulding and sheet forming processes, fiber formation etc.
[0102] The dispersible compounds of formula (Ia) or (Ib) are also
incorporated via dry blending, surface impregnation, suspension,
dispersion and other methods known in coatings technology.
[0103] When the colourants of the instant invention are used in a
film, the film is applied to the surface by, for example, the use
of an adhesive, or co-extruded onto the surface. A preformed film
may also be applied with heat which includes calendaring, melt
applications and shrink wrapping.
[0104] When a substrate is coated with a near infra red reflecting
and/or transmitting coating comprising a
bis-oxodihydroindolylen-benzodifuranone colourant, the coating
typically comprises a polymeric binder which can in principle be
any binder customary in industry, for example those described in
Ullmann's Encyclopedia of Industrial Chemistry, 5.sup.th Edition,
Vol. A18, pp. 368-426, VCH, Weinheim 1991. In general, it is a
film-forming binder based on a thermoplastic or thermosetting
resin, for example, a thermosetting resin. Examples thereof are
alkyd, acrylic, acrylamide, polyester, styrenic, phenolic,
melamine, epoxy and polyurethane resins.
[0105] For example, non-limiting examples of common coating binders
useful in the present invention include silicon containing
polymers, fluorinated polymers, unsaturated polyesters, unsaturated
polyamides, polyimides, crosslinkable acrylic resins derived from
substituted acrylic esters, e.g. from epoxy acrylates, urethane
acrylates, polyester acrylates, polymers of vinyl acetate, vinyl
alcohol and vinyl amine. The coating binder polymers may be
co-polymers, polymer blends or composites.
[0106] Coatings are frequently crosslinked with, for example,
melamine resins, urea resins, isocyanates, isocyanurates,
polyisocyanates, epoxy resins, anhydrides, poly acids and amines,
with or without accelerators.
[0107] The binder can be a cold-curable or hot-curable binder. In
many instances it is desirable to use
bis-oxodihydroindolylen-benzodifuranone pigment rather than dye. In
these instances, the binder can be a cold-curable or hot-curable
binder provided that the temperature is not high enough to cause
dissolution of the bis-oxodihydroindolylen-benzodifuranone pigment;
the addition of a curing catalyst may be advantageous. Suitable
catalysts which accelerate curing of the binder are described, for
example, in Ullmann's Encyclopedia of Industrial Chemistry,
5.sup.th Edition, Vol. A18, p. 469, VCH Verlagsgesellschaft,
Weinheim 1991.
[0108] The binder may be a surface coating resin which dries in the
air or hardens at room temperature. Exemplary of such binders are
nitrocellulose, polyvinyl acetate, polyvinyl chloride, unsaturated
polyester resins, polyacrylates, polyurethanes, epoxy resins,
phenolic resins, and especially alkyd resins. The binder may also
be a mixture of different surface coating resins. Provided the
binders are curable binders, they are normally used together with a
hardener and/or accelerator.
[0109] Examples of coating compositions containing specific binders
are: [0110] 1. coatings based on cold- or hot-crosslinkable alkyd,
acrylate, polyester, epoxy or melamine resins or mixtures of such
resins, if desired with addition of a curing catalyst; [0111] 2.
two-component polyurethane coatings based on hydroxyl-containing
acrylate, polyester or polyether resins and aliphatic or aromatic
isocyanates, isocyanurates or polyisocyanates; [0112] 3.
one-component polyurethane coatings based on blocked isocyanates,
isocyanurates or polyisocyanates which are deblocked during baking,
if desired with addition of a melamine resin; [0113] 4.
one-component polyurethane coatings based on a
Trisalkoxycarbonyltriazine crosslinker and a hydroxyl group
containing resin such as acrylate, polyester or polyether resins;
[0114] 5. one-component polyurethane coatings based on aliphatic or
aromatic urethaneacrylates or polyurethaneacrylates having free
amino groups within the urethane structure and melamine resins or
polyether resins, if necessary with curing catalyst; [0115] 6.
two-component coatings based on (poly)ketimines and aliphatic or
aromatic isocyanates, isocyanurates or polyisocyanates; [0116] 7.
two-component coatings based on (poly)ketimines and an unsaturated
acrylate resin or a polyacetoacetate resin or a
methacrylamidoglycolate methyl ester; [0117] 8. two-component
coatings based on carboxyl- or amino-containing polyacrylates and
polyepoxides; [0118] 9. two-component coatings based on acrylate
resins containing anhydride groups and on a polyhydroxy or
polyamino component; [0119] 10. two-component coatings based on
acrylate-containing anhydrides and polyepoxides; [0120] 11.
two-component coatings based on (poly)oxazolines and acrylate
resins containing anhydride groups, or unsaturated acrylate resins,
or aliphatic or aromatic isocyanates, isocyanurates or
polyisocyanates; [0121] 12. two-component coatings based on
unsaturated polyacrylates and polymalonates; [0122] 13.
thermoplastic polyacrylate coatings based on thermoplastic acrylate
resins or externally crosslinking acrylate resins in combination
with etherified melamine resins; and [0123] 14. paint systems based
on siloxane-modified or fluorine-modified acrylate resins.
[0124] Acrylic, methacrylic and acrylamide polymers and co-polymers
dispersible in water are readily used as a binder in the present
invention, for example, acrylic, methacrylic and acrylamide
dispersion polymers and co-polymers.
[0125] For example, coatings or films comprising acrylate polymers
are useful in the instant invention.
[0126] The coating composition can also comprise further
components, examples being solvents, pigments, dyes, plasticizers,
stabilizers, thixotropic agents, drying catalysts and/or levelling
agents. Examples of possible components are those described in
Ullmann's Encyclopedia of Industrial Chemistry, 5.sup.th Edition,
Vol. A18, pp. 429-471, VCH, Weinheim 1991.
[0127] Possible drying catalysts or curing catalysts are, for
example, organometallic compounds, amines, amino-containing resins
and/or phosphines. Examples of organometallic compounds are metal
carboxylates, especially those of the metals Pb, Mn, Co, Zn, Zr or
Cu, or metal chelates, especially those of the metals Al, Ti or Zr,
or organometallic compounds such as organotin compounds, for
example.
[0128] Examples of metal carboxylates are the stearates of Pb, Mn
or Zn, the octoates of Co, Zn or Cu, the naphthenates of Mn and Co
or the corresponding linoleates, resinates or tallates.
[0129] Examples of metal chelates are the aluminium, titanium or
zirconium chelates of acetylacetone, ethyl acetylacetate,
salicylaldehyde, salicylaldoxime, o-hydroxy-acetophenone or ethyl
trifluoroacetylacetate, and the alkoxides of these metals.
[0130] Examples of organotin compounds are dibutyltin oxide,
dibutyltin dilaurate or dibutyltin dioctoate.
[0131] Examples of amines are, in particular, tertiary amines, for
example tributylamine, triethanolamine, N-methyldiethanolamine,
N-dimethylethanolamine, N-ethylmorpholine, N-methylmorpholine or
diazabicyclooctane (triethylenediamine) and salts thereof. Further
examples are quaternary ammonium salts, for example
trimethylbenzylammonium chloride.
[0132] Amino-containing resins are simultaneously binder and curing
catalyst. Examples thereof are amino-containing acrylate
copolymers.
[0133] The curing catalyst used can also be a phosphine, for
example triphenylphosphine.
[0134] The coating compositions can also be radiation-curable
coating compositions. In this case, the binder essentially
comprises monomeric or oligomeric compounds containing
ethylenically unsaturated bonds, which after application are cured
by actinic radiation, i.e. converted into a crosslinked, high
molecular weight form.
[0135] Where the system is UV-curing, it generally contains a
photoinitiator as well. Corresponding systems are described in the
abovementioned publication Ullmann's Encyclopedia of Industrial
Chemistry, 5.sup.th Edition, Vol. A18, pages 451-453. In
radiation-curable coating compositions, the novel stabilizers can
also be employed without the addition of sterically hindered
amines.
[0136] The coating may also be a radiation-curable, solvent-free
formulation of photopolymerisable compounds. Illustrative examples
are mixtures of acrylates or methacrylates, unsaturated
polyester/styrene mixtures or mixtures of other ethylenically
unsaturated monomers or oligomers.
[0137] The coating compositions can comprise an organic solvent or
solvent mixture in which the binder is soluble. The coating
composition can otherwise be an aqueous solution or dispersion. The
vehicle can also be a mixture of organic solvent and water. The
coating composition may be a high-solids paint or can be
solvent-free (e.g. a powder coating material). Powder coatings are,
for example, those described in Ullmann's Encyclopedia of
Industrial Chemistry, 5.sup.th Edition, Vol. A18, pages 438-444.
The powder coating material may also have the form of a
powder-slurry (dispersion of the powder preferably in water).
[0138] Multilayer systems are possible where the
bis-oxodihydroindolylen-benzo-difuranone colourant may reside in a
coating which is then itself coated with another coating, such as a
protective coating.
[0139] When used in a coating, the compounds of formula (I) are
incorporated into the coating as dispersed particles via techniques
common in the art. The dispersion might be combined with the
incorporation into the coating composition by use of adequate
solvents.
[0140] The coating composition according to the invention can be
applied to any desired substrate, for example to metal, wood,
plastic, composite, glass or ceramic material substrates by the
customary methods, for example by brushing, spraying, pouring, draw
down, spin coating, dipping or electrophoresis; see also Ullmann's
Encyclopedia of Industrial Chemistry, 5.sup.th Edition, Vol. A18,
pp. 491-500.
[0141] The bis-oxodihydroindolylen-benzodifuranone colourant as
well as the white, black, colour, metallic or interference pigments
are present in the instant low heating compositions independently
from each other each in an "effective amount", that is an amount
that provides both the desired level of coloration for the
substrate or coating and also provides the desired near infra red
reflectance and transmittance. For example, the
bis-oxodihydroindolylen-benzodifuranone colourant, or the white,
black, colour, metallic or interference pigment are present in
amounts of about 0.01 to about 50% by weight of colourant of
formula (Ia) or (Ib) or white, black, colour, metallic or
interference pigment, based on the total weight of the composition,
especially 0.01-15%, preferably 0.1-10% or especially preferred
0.1-5% by weight, based on the total weight of the composition. In
the case of a coating, the composition is the fully dried and cured
coating. In the case that the
bis-oxodihydroindolylen-benzodifuranone colourant and the white,
black, colour, metallic or interference pigment are incorporated
into different compositions, for example different layers of a
multiple coating, then the percentages are based on the weight of
the respective (homogeneous) compositions, rather then on the total
weight of the final composite system.
[0142] It is also envisioned that when applied to the surface of a
substrate, the colourant of formula (Ia) or (Ib) may be present in
even higher amounts, even approaching 100%, such as in a thin
layer, or a layer which is part of a laminate structure.
[0143] A composition comprising the present colourants of formula
(Ia) or (Ib) may also optionally have incorporated therein or
applied thereto other additives such as anti-oxidants, UV
absorbers, hindered amine or other light stabilizers, phosphites or
phosphonites, benzofuran-2-ones, thiosynergists, polyamide
stabilizers, metal stearates, nucleating agents, fillers,
reinforcing agents, lubricants, emulsifiers, dyes, pigments,
dispersants, optical brighteners, flame retardants, antistatic
agents, blowing agents and the like.
[0144] The present invention also provides a near infra red inert
composition or article comprising an organic or inorganic
substrate, typically a polymeric substrate, and a
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib), or of an isomer or tautomer thereof, preferably a pigment
of formula (Ia) or (Ib) or an isomer or tautomer thereof, in an
amount effective to impart to the organic or inorganic substrate an
infra red reflectance of 20%, an infra red transmittance of 30%, or
a combined infra red reflectance and transmittance of 25%, each at
wavelengths from 850 to 1600 nm. The NIR inert composition or
article may be a coating, film, sheet or moulded or otherwise
shaped article.
[0145] For example, an infra red inert composition comprising a
thermoplastic, elastomeric, crosslinked or inherently crosslinked
polymer and an amount of a bis-oxodihydroindolylen-benzodifuranone
colourant of formula (Ia) or (Ib) effective to impart to the
composition an infra red reflectance of 20%, an infra red
transmittance of .gtoreq.30%, or a combined infra red reflectance
and transmittance of .gtoreq.25%, each at wavelengths from 850 to
1600 nm.
[0146] Also provided is a near infra red inert article comprising a
substrate which is coated with a near infra red inert coating or
film comprising a bis-oxodihydroindolylen-benzodifuranone colourant
of formula (Ia) or (Ib).
[0147] A further embodiment of the invention provides a method for
laser welding a layered article wherein a
bis-oxodihydroindolylen-benzodifuranone colourant of formula (Ia)
or (Ib) is incorporated into a polymeric composition which is in
contact with a surface of a meltable substrate, preferably a
polymeric substrate, containing a NIR absorbing material, such as a
carbon black pigmented polymer, then NIR radiation, as from a
laser, is passed through the layer containing the pigments of the
invention to the underlying NIR absorbing material generating
enough heat at the point of irradiation to "laser weld", that is
melt together the two materials.
[0148] The lasers used are commonly available lasers which emit at
wavelengths between about 700 and about 2000 nm, for example,
between about 800 and about 1500 nm.
[0149] FIG. 1A is a daylight picture of a sample according to
example 18. FIG. 1B shows a picture of a sample according to
example 18 under infra red light exposure using a filter
(passthrough 715-1000 nm).
[0150] FIG. 2 is an electronic absorption spectrum of the printed
polyester substrate according to example 18, measured against blank
Melinex.RTM. (reference 306, thickness 100 .mu.m) with a Lambda.TM.
15 UV-VIS spectrophotometer (Perkin-Elmer).
[0151] FIG. 3A is a daylight picture of a sample according to
example 19.
[0152] FIG. 3B is a picture of a sample according to example 19
under infra red light exposure using a filter (passthrough 715-1000
nm).
[0153] FIG. 4A is a picture of the samples setup according to
example 21, wherein the print on polyester according to example 18
is laid on top of the right side of two adjacent labels, the top
one printed with an IR absorber and the bottom one printed with C.
I. Pigment Black 7.
[0154] FIG. 4B is a picture of the same samples setup according to
example 21 under infra red light exposure using a filter
(passthrough 715-1000 nm).
[0155] FIG. 5A is a daylight picture of the samples setup according
to example 22), wherein an ink comprising the compound according to
example 12b of WO 00/24 736 is printed on a paper sheet, the left
half of which has previously been printed with an ink comprising an
IR absorber.
[0156] FIG. 5B is a picture of the same sample according to example
22 under infra red light exposure using a filter (passthrough
715-1000 nm).
[0157] FIG. 1A, FIG. 1B, FIG. 3A, FIG. 3B, FIG. 4A, FIG. 5A and
FIG. 5B are all colour photographic pictures which are digitalized
then converted to grayscale.
[0158] The examples that follow illustrate the invention, without
limiting the scope thereof (unless otherwise specified, "%" is
always % by weight):
EXAMPLE 1
[0159] A 12% millbase is prepared by dispersing 5.4 parts of the
compound according to example 12b of WO00/24 736 in 9.0 parts of
butyl acetate for 15 minutes in a Skandex.RTM. disperser. 25.4
parts of Maprenal.RTM. MF 650 (30% in isobutanol/n-butanol/xylene
20:1:1, Solutia Inc.) are added and the mixture is dispersed again.
Then, the pigment concentration is let down to 6% by adding 25.4 g
cellulose acetobutyrate and 33.8 g of Dynapol.RTM. H700 and finally
mixing. A layer is bar-coated on a glass plate with a 100 .mu.m
spiral bar. The transmission at 1200 nm is 68%. The
CIE-colouristics are: L*=26.8, C*=1.3, h=290.2. The transmission
value is enhanced to 77% by additionally using a dispersant.
EXAMPLE 2
[0160] It is proceeded similarly as in example 1, with the
difference that the pigment concentration is decreased to 1%. The
transmission at 1200 nm is 92%.
EXAMPLE 3
[0161] The compound according to example 12b of WO00/24736 is
treated by wet-milling for 1 hour at 40.degree. C. in the 10-fold
amount of isopropanol (Skandex.RTM.), then filtered and dried. An
easily dispersible pigment powder is obtained.
EXAMPLE 4
[0162] An about 0.3 mm thick PVC sheet comprising 0.2% of the
pigment powder according to example 3 is prepared in conventional
manner on a two-roll mill at 150-160.degree. C. The transmission in
the wavelength range from 850 to 1600 nm varies from 65% to
83%.
EXAMPLE 5
[0163] An about 0.4 mm thick flexible PVC film comprising 0.2% by
weight of the pigment powder according to example 3 is prepared in
conventional manner on a two-roll mill at 150-160.degree. C. The
temperature increase is determined in a heat box according to ASTM
D4803-97 (2002)e1 under a commercial 250 W IR lamp. The PVC film
shows about 7.degree. C. less heat build up, as compared with a
similar film containing 0.2% of commercial C Black FW 200 (Evonik,
C. I. Pigment Black 7).
EXAMPLE 6
[0164] Polypropylene samples comprising 0.2% of the pigment powder
according to example 3 are prepared by extrusion and injection
moulding at 220.degree. C. The results are comparable to those of
example 4. Especially remarkable is the disapparition of the
absorption peak at around 1.2 .mu.m, at which wavelength the
transmittance (.about.77%) is even better than that of colourless
polypropylene (.about.74%). The CIE-colouristics are: L*=29.1,
C*=3.5, h=79.4.
EXAMPLE 7
[0165] A mixture of the pigment powder according to example 3 and a
LDPE-wax (1:1) is introduced at 0.1% in polypropylene (HF 420 FB,
Borealis) at 260.degree. C./56.2 bar (800 psi) pressure and spun to
80 dtex/10 filaments with a stretching ratio of 1:4. A fine black
yarn is obtained, which is woven to a polypropylene fabric showing
about 10.degree. C. less heat uptake and a lower NIR signature,
compared with a similar fabric comprising with C. I. Pigment Black
7.
EXAMPLE 8
[0166] An about 25 .mu.m LDPE (Lupolen.RTM. 1840D, Basell) blow
film thick comprising 1% of the pigment powder according to example
3 is prepared in conventional manner by extrusion and blow moulding
at 200.degree. C. The transmission in the wavelength range from 800
nm to 1500 nm varies from 87 to 90%. A comparative sample comparing
commercial C Black FW 200 (Evonik) shows values of 38 to 56%.
EXAMPLE 9
[0167] Polyethyleneterephthalate (PET Arnite.RTM. D04-300, DSM)
samples comprising 0.02% of the pigment powder according to example
3 are prepared by extrusion and injection moulding at 280.degree.
C. The results are similar to those of example 4.
EXAMPLE 10
[0168] Polymethylmethacrylate (PMMA 6N Glasklar.TM., Rohm GmbH,
Darmstadt) samples comprising 0.05% of the pigment powder according
to example 3 are prepared by extrusion and injection moulding at
200.degree. C. The results are similar to those of example 4.
EXAMPLE 11
[0169] It is proceeded similarly to example 6, with the difference
that 1% of titanium white is further added to the composition. An
attractive neutral grey is obtained, the saturation and the hue of
which are almost identical to those of carbon black, however with a
much higher reflectivity:
TABLE-US-00001 L* C* h example 5 67.8 3.6 246.4 Pigment Black 7
26.5 3.0 259.9
EXAMPLE 12
[0170] Coatings comprising the pigment powder according to example
3 are sprayed onto a steel plate onto which a primer comprising
titanium white and aluminum flakes has been previously applied,
giving a black appearance. The reflectance is significantly higher
than that of the primer itself in the region from 800 nm to 1.35
.mu.m, and nearly identical from 1.35 .mu.m to 1.6 .mu.m.
EXAMPLE 13
[0171] A mill base is prepared by dispersing in a Skandex.RTM. 15.0
parts of the compound according to example 12b of WO 00/24 736,
13.5 parts Ciba.RTM. EFKA.RTM. 4585, 1.2 parts dimethylethanolamine
(DMEA 10%), 0.3 parts Ciba.RTM. EFKA.RTM. 2550 and 70.0 parts
deionized water. 2 parts of this mill base are then dispersed into
18 parts of a waterborne polyurethane-acrylate hybrid clear system
(0.54 parts Maprenal.RTM. MF900 W/95, 0.8 parts Surfynol.RTM. 104E,
0.3 parts Surfynol.RTM. MD20, 0.4 parts Envirogen.RTM. AE02, 5.51
parts butylglycol, 2 parts n-butanol, 0.2 parts Dow.RTM. DC57, 3.5
parts Viscalex.RTM. HV30, 0.25 parts DMEA, 37.25 parts APU.RTM.
1012 and 49.25 parts deionized water). Coatings comprising 4%
pigment on solids are sprayed onto aluminum plates and a steel
plate onto which a white primer has been previously applied giving
a black appearance.
EXAMPLE 14
[0172] A mill base is prepared by dispersing in a Skandex.RTM. 2%
of the pigment powder according to example 3 in a PES-CAB two coat
system. Coatings are sprayed onto aluminum plates giving a black
appearance.
EXAMPLE 15
[0173] A varnish is prepared by dispersing in a Skandex.RTM. 6% of
the compound according to example 12b of WO 00/24 736,
nitrocellulose and alcohol. This ink is applied with a hand coater
(20.mu. it wet film thickness) onto a white substrate, on which an
image has been applied using an ink comprising a slightly coloured
NIR absorber. Visually, the whole sample appears grey and the image
can very uneasily be distinguished. However, when the samples are
photographed using an IR filter (715-1000 nm), an image is obtained
which is very similar to the image before application of the
compound according to example 12b of WO00/24 736. When a perylene
black is used instead of the compound according to example 12b of
WO00/24 736, violet prints are obtained instead of desirably grey
prints.
EXAMPLE 16
[0174] A varnish is prepared by dispersing in a Skandex.RTM. 3% of
the pigment powder according to example 3 in a vinyl binder system
(Movital.RTM. B20H, ethoxypropanol, methoxypropylacetate,
diacetonealcohol). This ink is applied with a by hand-coater
n.degree. 2 (12 .mu.m wet film thickness) onto an aluminium foil to
provide a grayish black print. When a perylene black is applied
instead of the pigment powder according to example 3, violet prints
are obtained instead of desirably grey prints.
EXAMPLE 17
Clear Varnish Preparation
[0175] 1 Kg of clear varnish is prepared by mild stirring at
23.degree. C. of a formulation containing 30 g Citrofoll.RTM. BII
(ATBC, Jungbunz-lauer), 150 g nitrocellulose chips AH27 containing
20% of ATBC (Christ), 10 g ethylcellulose N7 (Herkules), 40 g
Kunstharz SK (Degussa), 100 g 1-ethoxypropanol, 200 g ethylacetate
and 470 g ethanol. The thus obtained clear varnish has a viscosity
of 18 seconds (Ford Cup n.degree. 4).
EXAMPLE 18
[0176] A nitrocellulose ink is prepared in a Skandex.RTM. by
dispersing for 2 hours in a 400 ml glass bottle 15 parts of the
pigment powder according to example 3 and 230 g of glass beads of 2
mm diameter into 85 parts of the clear varnish according to example
17. Application by hand-coater n.degree. 2 (12 .mu.m wet film
thickness) on transparent polyester foil (Melinex.RTM., reference
306, thickness 100 .mu.m) results in a black print. Photography in
daylight without filter shows an intensely coloured black image
(see FIG. 1A and FIG. 2), whereas photography under infra red light
using a filter (passthrough 715-1000 nm) shows a transparent
colourless image of the print (see FIG. 1B).
EXAMPLE 19
Comparative
[0177] A nitrocellulose ink is prepared by stirring with a
Dispermat.RTM. at 6000 rpm for 20 minutes in a 400 ml glass bottle
25 parts Microlith.RTM. Black C-A (containing 60% C. I. Pigment
Black 7), 2 parts nitrocellulose Chips AH27 (containing 20% of
ATBC, Christ), 3 parts Joncryl.RTM. 68 (BASF), 5 parts Dowanol.RTM.
PM (Fluka), 18 parts ethylacetate and 47 parts ethanol. Application
by hand-coater n.degree. 2 (12 .mu.m wet film thickness) on
transparent polyester foil (Melinex.RTM., reference 306, thickness
100 .mu.m) results in a black print. Both photographs in daylight
and under infra red light using a filter (passthrough 715-1000 nm)
show an intensely coloured black image (see FIG. 3A and FIG.
3B).
EXAMPLE 20
Comparative Coloristic Measurements of Examples 18 and 19
[0178] The samples according to examples 18 and 19 are
coloristically measured with CGREC for Windows Version 2.61.05.
Comparative example 19 is measured against example 18 taken as
reference. The shade of the print obtained according to comparative
example 19 is much yellower than that according to example 18
(.DELTA.H*=2.6) and the colour strength of the print obtained
according to comparative example 19 is 34% lower than that
according to example 18:
TABLE-US-00002 colour strength L* C* h [%] .DELTA.H* contrast paper
light area 96.3 4.0 91.8 dark area 33.1 2.2 31.5 example 18 over
light 33.2 2.2 32.4 100 -- over dark 26.5 1.4 8.6 example 19 over
light 33.4 2.2 36.4 66 2.6 over dark 32.6 3.3 81.3
EXAMPLE 21
[0179] The print on polyester according to example 18 is laid on
top of part of two adjacent labels, the first printed with an IR
absorber and the second printed with C. I. Pigment Black 7. This
set up is photographed both in daylight (see FIG. 4A) and under
infra red light using a filter (passthrough 715-1000 nm) (see FIG.
4B). The label printed with an IR absorber (top left) appears
almost colourless under daylight and grey under IR light, but where
it is covered by the print on polyester according to example 18
(top right), it is entirely masked under daylight (FIG. 4A) and
appears only under IR light (FIG. 4B). The label printed with
carbon black (bottom left) appears black under daylight and dark
grey under IR light (likely due to some partial IR reflection), but
where it is covered by the print on polyester according to example
18 (bottom right), it is entirely masked under daylight (FIG. 4A)
and appears only under IR light (FIG. 4B). That is, a pattern
printed for example with carbon black or another colourless or
coloured IR absorber, covered with a print layer according to
example 18 is hidden under daylight but clearly recognizable under
infra red light using a filter (passthrough 715-1000 nm), enabling
excellent marking or security applications.
EXAMPLE 22
[0180] A security element is prepared by overprinting an ink
containing the pigment powder according to example 3 on top of a
print containing an IR absorber. An IR absorber containing offset
ink is first printed on the left half of paper sheets with a
Prufbau.RTM. apparatus (1.3 g/m.sup.2). An ink according to example
18 is then applied on the bottom part of the previous print by
hand-coater n.degree. 2 (12 .mu.m wet film thickness). Photography
in daylight shows almost no difference between the left part with
the ink according to example 18 printed on an underlayer with the
IR absorber (see FIG. 5A), whereas photography under infra red
light using a filter (passthrough 715-1000 nm) reveals a large
difference (see FIG. 5B).
EXAMPLE 23
[0181] It is proceeded as in example 7, with the difference that
the pigment powder according to example 3 is introduced at 1.0% in
polypropylene and the fabric is used to manufacture camouflage
nets.
EXAMPLE 24
[0182] It is proceeded similarly to example 1. A millbase is
prepared by dispersing 1.8 parts of the compound according to
example 12b of WO00/24 736 in 3.6 parts of butyl acetate for 15
minutes in a Skandex.RTM. disperser. 26.5 parts of Maprenal.RTM. MF
650 are added and the mixture is dispersed again. Then, the pigment
concentration is let down to 2% by adding 26.5 parts of cellulose
acetobutyrate and 35.0 parts of Dynapol.RTM. H700 and finally
mixing. A layer is bar-coated on glass with a 100 .mu.m spiral bar.
The transmission in the wavelengths from 800 to 1500 nm varies from
77% to 87%.
EXAMPLE 25
Comparative
[0183] It is proceeded similarly to example 24, with the difference
that C Black FW 200 (Evonik, C. I. Pigment Black 7) is used instead
of the compound according to example 12b of WO 00/24 736. The
transmission in the wavelengths from 800 to 1500 nm shows values
around 22%.
EXAMPLE 26
[0184] It is proceeded as in example 1, with the difference that
the pigment concentration is decreased to 1%. The paint is sprayed
onto aluminium plates giving a clean black appearance. A typical
thermosetting acrylic top coat is then applied, which contains a
combination of UV absorber and hindered amines (HALS), like for
example Tinuvin.RTM. 900 and Tinuvin.RTM. 292 (both Ciba).
EXAMPLE 27
[0185] A 50:50 pigment:aluminium reduction is prepared by mixing
the millbase according to example 26 and an 8% aluminium base paint
containing a 60% aluminium paste (Silverline.RTM. SS3334AR). The
paint is sprayed onto aluminium plates giving a shiny black
appearance. A typical thermosetting acrylic top coat is then
applied, which contains a combination of UV absorber and hindered
amines (HALS), like for example Tinuvin.RTM. 900 and Tinuvin.RTM.
292 (both Ciba).
EXAMPLE 28
[0186] A 20:80 pigment:TiO.sub.2 white reduction is prepared by
mixing the millbase according to example 26 and a white base paint
containing 20% of titanium dioxide (Kronos.RTM. 2310). The paint is
sprayed onto aluminium plates giving a grey appearance. A typical
thermosetting acrylic top coat is then applied, which contains a
combination of UV absorber and hindered amines (HALS), like for
example Tinuvin.RTM. 900 and Tinuvin.RTM. 292 (both Ciba).
EXAMPLE 29
[0187] A millbase is prepared by dispersing 0.6 parts of the
compound according to example 12b of WO 00/24 736 and titanium
dioxide (Kronos.RTM. 2310) in 3.8 parts of xylene, then in 29.2
parts of an alkydmelamine lacquer based on F310.TM. (60% in
Solventnaphtha.RTM. 100, Bayer) and 5.0 parts of the aminoplast
crosslinker Cymel.RTM. 327 (Cytec) in a Skandex.RTM. disperser. A
layer is bar-coated with a 100 .mu.m spiral bar on an aluminium
plate and baked in the oven for 30 minutes at 130.degree. C. A grey
colour is obtained.
EXAMPLE 30
[0188] The pigment powder according to example 3 is spun at 0.1%
concentration into PES fibres (Polyester granulate GL 6105 type,
Kuag Elana GmbH) at 110 dtex/24 filaments. A fine black yarn is
obtained, which is weaved to a polyester fabric showing less heat
uptake and a lower NIR signature as a comparable fabric comprising
0.1% C. I. Pigment Black 7.
EXAMPLE 31
[0189] It is proceeded as in example 30, with the difference that
the concentration of the pigment powder according to example 3 is
increased to 1%.
EXAMPLE 32
`Let-Down` Clear
[0190] A `let-down` clear is prepared by stirring 29 parts Binder A
(Bayhydrol.RTM. VPLS 2378, Bayer) and 40 parts Binder B
(Bayhydrol.RTM. VPLS 2341, Bayer), then adding individually 2.5
parts butyl glycol and 6 parts n-methyl-pyrrolidone under stirring.
The mixture is stirred for 15 minutes prior to further component
additions. 15 parts Crosslinker A (Bayhydur.RTM. BL 5140, Bayer)
and 7.5 parts Crosslinker B (Trixene.RTM. BI 7986) are added
separately under stirring. The subsequent mixture is stirred for 1
hour prior to further additions to ensure all components are
homogeneously mixed.
EXAMPLE 33
Titanium Dioxide Pigment Paste
[0191] A continuous phase is prepared by mixing 38.5 parts
de-ionised water, 4.2 parts of Efka.RTM. 4580 (pigment dispersant,
Ciba), 0.3 parts of Efka.RTM. 2550 (antifoam agent, Ciba) and 0.4
parts of Optigel.RTM. SH (anti-settlement agent), using a disperser
equipped with a Cowles blade (toothed blade). Once homogeneous,
55.0 parts titanium dioxide pigment (Kronos.RTM. 2310) are added
under stirring. Once all the pigment is incorporated, the pH of the
slurry is adjusted in the range 7.5 to 8.5 by use of a 10% aqueous
solution of dimethyl-ethanolamine. The slurry is then predispersed
using the same disperser/Cowles blade combination for 30 minutes to
ensure large pigment agglomerates are adequately `wetted-out` in
the continuous phase. The `wetted-out` slurry is transferred to a
re-circulation dispersion mill filled with zirconia grind media
until maximum particle size of the dispersed pigment is .ltoreq.10
.mu.m according to a Hegmann grind gauge.
EXAMPLE 34
Comparative Carbon Black Pigment Paste
[0192] A continuous phase is prepared by mixing 65.7 parts
deionised water, 10.0 parts of Efka.RTM. 4580 (pigment dispersant,
Ciba) and 0.3 part of Efka.RTM. 2550 (antifoam agent, Ciba) with a
disperser equipped with a Cowles blade (toothed blade). Once
homogeneous, 12.0 parts Colour Black.TM. FW 200 (carbon black
pigment, Evonik) are added under stirring. Once all the pigment is
incorporated, the pH of the slurry is adjusted in the range 7.5 to
8.5 by use of a 10% aqueous solution of dimethylethanolamine. The
slurry is then further processed as in example 33.
EXAMPLE 35
NIR-Inert Black Pigment Paste
[0193] A continuous phase is prepared by mixing 61.2 parts
deionised water, 12.5 parts of Efka.RTM. 4580 (pigment dispersant,
Ciba) and 0.3 parts of Efka.RTM. 2550 (antifoam agent, Ciba) by
stirring using a disperser equipped with a Cowles blade (toothed
blade). Once homogeneous, 20.0 parts of the pigment powder
according to example 3 are added under stirring to the continuous
phase. Once all the pigment is incorporated, the pH of the slurry
is adjusted in the range 7.5 to 8.5 by use of a 10% aqueous
solution of dimethyl-ethanolamine. The slurry is then further
processed as in example 33.
EXAMPLE 36
Deep Grey NIR Reflective Primer; 70:30 White:Black
[0194] To 39 parts of `let-down` clear according to example 32, 28
parts titanium dioxide pigment paste according to example 33 and 32
parts IR-reflective black paste according to example 35 are added
separately under stirring. Once all pastes are completely
homogenised, 1 part of Efka.RTM. 3570 (levelling additive, Ciba) is
added under stirring. The pH of the primer is adjusted by the
addition of a 10% aqueous solution of dimethylethanolamine until a
stable pH in the range 7.5 to 8.5 is obtained. To prepare the
primer for final application, deionised water is added to the
mixture until a viscosity of 30-35 seconds in a DIN 4 viscosity
flow cup (23.degree. C.) is obtained. This primer formulation is
applied onto 1.0 mm thick glass panels using a drawdown bar to a
dry film thickness of 40-50 .mu.m, sufficient for full optical
(visible light) opacity. After a flash off period of 30 minutes at
.about.23.degree. C., the panels are pre-baked for 15 minutes at
80.degree. C. to drive off excess water and solvent, followed by a
stowing cycle of 30 minutes at 150.degree. C. to achieve full
cure.
EXAMPLE 37
Middle Grey NIR Reflective Primer; 85:15 White:Black)
[0195] To 44 parts of `let-down` clear according to example 32, 37
parts titanium dioxide pigment paste according to example 33 and 18
parts IR-reflective black paste according to example 35 are added
separately under stirring. Once all pastes are completely
homogenised, 1 part of Efka.RTM. 3570 (levelling additive, Ciba) is
added under stirring. The pH of the primer is adjusted by the
addition of a 10% aqueous solution of dimethylethanolamine until a
stable pH in the range 7.5 to 8.5 is obtained. To prepare the
primer for final application, deionised water is added to the
mixture until a viscosity of 30-35 seconds in a DIN 4 viscosity
flow cup (23.degree. C.) is obtained, which is then applied onto
glass panels according to the procedure of example 36.
EXAMPLE 38
Black NIR-Inert Primer
[0196] It is proceeded in analogy to example 36, with the
difference that only the NIR-inert black paste according to example
35 and no titanium dioxide are used as pigments.
EXAMPLE 39
Comparative Middle Grey Primer; 95:5 White:Black
[0197] To 46 parts of `let-down` clear according to example 32, 43
parts titanium dioxide pigment paste according to example 33 and 11
parts carbon black pigment paste according to example 34 are added
separately under stirring. Once all pastes are completely
homogenised, 1 part of Efka.RTM. 3570 (levelling additive, Ciba) is
added under stirring. The pH of the primer is adjusted by the
addition of a 10% aqueous solution of dimethylethanolamine until a
stable pH in the range 7.5 to 8.5 is obtained. To prepare the
primer for final application, deionised water is added to the
mixture until a viscosity of 30-35 seconds in a DIN 4 viscosity
flow cup (23.degree. C.) is obtained. This primer formulation is
then applied onto 1.0 mm thick glass panels according to the
procedure of example 36.
EXAMPLE 40
Comparative Black Primer
[0198] It is proceeded according to example 36, with the difference
that the carbon black pigment paste according to example 34 is used
as the only pigment.
[0199] The approximative transmission and the reflection of the
cured glass panels according to examples 36, 37, 38, 39 and 40 are
then measured with a Lambda.TM. 900 UV/VIS spectrophotometer
(Perkin Elmer) in the near infra-red spectral range from 700 to
1200 nm. As compared with the conventional, carbon black comprising
grey primer according to comparative example 39, the grey primers
according to examples 36 and 37 show about 3 to 6 times higher NIR
reflectance as well as a significant NIR transmission above about
850 nm (no transmission is observed with comparative example 39
comprising carbon black). The black sample according to example 38
is also superior to the black sample according to comparative
example 40 both in transmission and in reflection throughout the
measured range. Above about 1000 nm, the sample according to
example 38 transmits most NIR radiation and reflects a large part
of the remaining, not transmitted NIR radiation, while the sample
according to comparative example 40 transmits no NIR radiation and
reflects about 4 times less NIR radiation than the sample according
to example 38.
[0200] Similar results are obtained when the waterborne stoving
formulation according to examples 32 to 40 is replaced by stoving
solventborne primers and primers formulated for different curing
conditions, for example ambient cured, solventborne and waterborne
acrylic (and/or polyester)+isocyanate and epoxide+polyamine,
2-component primer systems.
EXAMPLE 41
[0201] According to procedures well-known to skilled artisans, the
grey primer formulation according to example 37 is applied to a
scale model car body by spraying. A pigmented layer comprising the
pigment according to example 2 of EP application 08 157 426.1 (C.
I. Pigment Yellow 139) and a clear coat, each based on coating
formulations similar to and compatible with those of example 32 to
40, are then applied wet-on-wet. Curing then leads to a very
uniform colouration independently of the angle of view. The model
car body is then mounted on a chassis equipped with a remote
control. Remote controls of relatively low heat specifications can
be used without failure under sun exposure, decreasing the overall
costs.
EXAMPLE 42
[0202] According to procedures well-known to skilled artisans, the
primer formulation according to example 36 is applied to an
automotive hood by spraying (dry film thickness .about.50 .mu.m).
After curing, the primer layer is overcoated by spraying first a
layer of the red composition according to example 1 of EP 1 549 706
B1 (dry film thickness .about.20 .mu.m), then in a wet-on-wet
process with an usual protective transparent topcoat layer
comprising UV absorbers and antioxidants (dry film thickness
.about.50 .mu.m). The red car hood uptakes only little heat under
sun exposure and leads to enhanced durability of the coating and
longer time to failure of the onboard electronic equipment (engine
and brakes control systems).
* * * * *