Title: IR reflective pigment compositions
Abstract: The present invention relates to IR reflective black pigment compositions comprising a halogenated copper phthalocyanine such as C.I. Pigment Green 7 and a perylenetetracarboxylic acid diimide such as C.I. Pigment Violet 29. The compositions are characterized by an IR reflection spectrum with a positive slope in the wavelength range between 800 and 900 nm when incorporated as coloring agents in coatings or plastics. The inventive IR reflective black pigment compositions are useful for coloring high molecular weight materials like coatings, inks and plastics.
Patent Number: 6,989,056 Issued on 01/24/2006 to Bäbler
| Inventors:
|
Bäbler; Fridolin (Teresópolis, BR)
|
| Assignee:
|
Ciba Specialty Chemicals Corporation (Tarrytown, NY)
|
| Appl. No.:
|
945515 |
| Filed:
|
September 20, 2004 |
| Current U.S. Class: |
106/413; 106/31.75; 106/31.76; 106/31.77; 106/31.78; 106/410; 106/411; 106/412; 47/57.6; 162/162; 252/8.57; 252/587; 424/69; 508/251; 524/88 |
| Current Intern'l Class: |
C09B 67/22 (20060101); C09B 67/20 (20060101) |
| Field of Search: |
106/410,411,412,413,317.5,317.6,317.7,317.8
47/576
162/162
252/857,587
424/69
427/384
508/251
524/88
|
References Cited [Referenced By]
U.S. Patent Documents
| 4436852 | Mar., 1984 | Bäbler.
| |
| 4555463 | Nov., 1985 | Hor et al.
| |
| 5472494 | Dec., 1995 | Hetzenegger et al.
| |
| 5540998 | Jul., 1996 | Yamada et al.
| |
| Foreign Patent Documents |
| 1160402 | Jan., 1984 | CA.
| |
| 03/080742 | Oct., 2003 | WO.
| |
Other References
Derwent Abstract for DD 296298, Nov. 1991.
Chemical Abstract AN 1993:541282 for DD 301159, Oct. 1992.
Chemical Abstract AN 1976:422766 for DE 2451780, Feb. 1976.
Chemical Abstract AN 1981:158047 for EP 23318, Feb. 1981.
Derwent Abstract 2002-287213 [33] for JP 2002003741, Jan. 2002.
Derwent Abstract 1993-081312 [10] for JP 05027481, Feb. 1993.
|
Primary Examiner: Green; Anthony J.
Attorney, Agent or Firm: Loggins; Shiela A.
Parent Case Text
This application claims the benefit of U.S. Provisional Application No. 60/506,282,
filed Sep. 26, 2003
Claims
I claim:
1. An IR reflective black pigment composition comprising 20 to 80 parts by weight
of a halogenated copper phthalocyanine of the formula I
##STR4##
wherein X is chlorine and/or bromine and n is a number from 1 to 4,
and 20 to 80 parts by weight of a perylenetetracarboxylic acid diimide of formula
II
##STR5##
wherein the parts by weight of the halogenated copper phthalocyanine of formula
I and the perylenetetracarboxylic acid diimide of formula II total 100 parts by
weight, and which composition is characterized by an IR reflection spectrum with
a positive slope in the wavelength range between 800 and 900 nm when incorporated
as coloring agent in coatings or plastics.
2. An IR reflective black pigment composition according to claim 1, in which
the halogenated copper phthalocyanine is C.I. Pigment Green 7 or C.I. Pigment Green
36 or a mixture thereof.
3. An IR reflective black pigment composition according to claim 1, in which
the halogenated copper phthalocyanine is C.I. Pigment Green 7.
4. An IR reflective black pigment composition according to claim 1, comprising
from 25 to 70 parts by weight of the halogenated copper phthalocyanine of formula
I and from 30 to 75 parts by weight of the perylenetetracarboxylic acid diimide
of formula II.
5. An IR reflective black pigment composition according to claim 4, comprising
from 35 to 65 parts by weight of the halogenated copper phthalocyanine of formula
I and from 35 to 65 parts by weight of the perylenetetracarboxylic acid diimide
of formula II, wherein the halogenated copper phthalocyanine is C.I. Pigment Green
7 and the perylenetetracarboxylic acid diimde is C.I. Pigment Violet 29.
6. An IR reflective black pigment composition according to claim 1, wherein the
perylenetetracarboxylic acid diimide has a specific surface area in the range of
10 to 40 m
2/g.
7. An IR reflective black pigment composition according to claim 1, wherein the
perylenetetracarboxylic acid diimide is C.I. Pigment Violet 29 and has a specific
surface area in the range of equal to or greater than about 40 m
2/g.
8. An IR reflective black pigment composition according to claim 7, wherein the
C.I. Pigment Violet 29 has a specific surface area in the range of equal to or
greater than about 50 m
2/g.
9. An IR reflective black pigment composition according to claim 3, wherein the
C.I. Pigment Green 7 has an average particle size of less than 0.2 μm as
measured by an electron micrograph.
10. An IR reflective black pigment composition according to claim 1, wherein
the composition is co-blended, optionally in the presence of an additive or additives
by a dry or wet milling process.
11. An IR reflective black pigment composition according to claim 1, wherein
the composition is co-blended by a dry blending process.
12. An IR reflective black pigment composition according to claim 10, wherein
the mixture is co-blended in the presence of an additive selected from the group
consisting of texture improving agents, anti-flocculating agents, extenders and
mixtures thereof.
13. An IR reflective black pigment composition according to claim 10, wherein
the additive or additives are added in an amount of 0.5 to 25% by weight based
on the pigment mixture.
14. An IR reflective black pigment composition according to claim 12, wherein
the texture improving agent is selected from the group consisting of fatty amines
or fatty acids having at least 12 carbon atoms, amides, esters or salts of fatty
acids and mixtures thereof, fatty alcohols or ethoxylated fatty alcohols, diols
, polyols, epoxidized soy bean oil, waxes, resin acids and resin acid salts.
15. An IR reflective black pigment composition according to claim 12, wherein
the anti-flocculating agent is a copper phthalocyanine derivative, a quinacridone
or a dihydroquinacridone derivative.
16. An IR reflective black pigment composition according to claim 10, wherein
the additive is quinacridone monosulfonic acid or quinacridone monosulfonic acid
aluminum salt or 3,5-dimethylpyrazol-1 -methyl quinacridone, or a mixture thereof.
17. An IR reflective black pigment composition according to claim 1, wherein
the IR reflective black pigment composition is further combined with an effect
pigment to produce a mixture, wherein the IR reflective black pigment is between
about 90 to 10 weight % of the total weight of the mixture.
18. A method for preparing an IR reflective black pigment composition according
to claim 1, which comprises co-blending dry pigment powders of the halogenated
copper phthalocyanine and the perylenetetracarboxylic acid dilmide, optionally
in the presence of additives, in a horizontal or vertical blender.
19. A method for coloring a solid or liquid substrate comprising incorporating
an effective pigmenting amount of an IR reflective black pigment composition as
defined in claim 1 into said substrate.
20. A method according to claim 19, wherein the substrate is a high molecular
weight organic material having a molecular weight in the range of from 10
3
to 10
8 g/mol.
21. A method according to claim 20, wherein the high molecular weight organic
material is selected from the group consisting of cellulose ethers and esters,
natural resins or synthetic resins, alkyd resins, phenolic plastics, polycarbonates,
polyolefins, polystyrene, polyvinyl chloride, polyamides, polyurethanes, polyesters,
rubber, casein, silicone and silicone resins, singly or in mixtures.
22. A method according to claim 20, wherein the high molecular weight organic
material is an industrial or automotive paint, an ink, a security ink, a powder
or a UV/EB cured coating system.
23. A method of claim 19, wherein the substrate is paper, leather, a solid or
liquid polymeric material, mineral oil, an inorganic substance, a cosmetic material
or a seed.
24. A method for coloring a substrate comprising applying a coating composition
that contains an effective pigmenting amount of an IR reflective black pigment
composition as defined in claim 1 to said substrate.
25. A method as defined in claim 24 wherein the IR reflective black pigment composition
further comprises an inorganic or organic effect pigment.
26. A method for coloring a substrate according to claim 25 in which said effect
pigment is a pearlescent mica pigment.
Description
SUMMARY
The present invention relates to IR reflective pigment compositions and methods
of their preparation and application.
BACKGROUND
Effect pigments, also known as gloss or lustrous pigments, are well known
as pigments that produce unique coloristic effects. The optical properties of effect
pigments are governed by reflection and/or interference phenomenon. In particular,
finishes containing an effect pigment produce a "flop effect" whereby the coloristic
characteristics of the finish change depending on the viewing angle. In general,
when a change in viewing angle results in a change in lightness, the effect is
referred to as "lightness flop", and when the change is in hue, the effect is referred
to as "color flop".
Due to their unique color characteristics, the market for effect pigments is
growing in such uses as cosmetics, inks, plastics and paints, and especially automotive
paints. Weather fast effect pigments are currently employed in large quantities
in the automotive paint industry.
IR reflective pigments are known in the market, and are used in the military,
construction, inks, plastics and coatings industries. Their demand is on the rise.
IR reflective inorganic pigments such as C.I. Pigment Black 30, a spinel formulated
primarily with nickel, manganese, chrome and iron, and C.I. Pigment Green 17, a
chromium green black hematite, have been known for many years and have become popular.
Although some of these pigments possess high IR reflectance, they have drawbacks
like low color strength, abrasiveness, and toxicity issues.
The literature also describes IR reflective organic pigments. In particular certain
perylenetetracarboxylic acid diimide pigments show favorable IR reflection behavior
when used as a black pigment or shading component for military camouflage and other
purposes. Such perylenetetracarboxylic acid diimide pigments are described in the
German Patents DE 24 51 780 B1 and DE 301 159 C.
German Patent DE 296 298 C describes dark green camouflage pigment mixtures
comprising perylenetetracarboxylic acid-bis-N,N′-2-aminoethyl imide and/or
5,5-dichloro indigo.
U.S. Pat. No. 5,540,998 relates to a solar heat shielding coating composition
which consists mainly of two or more of organic pigments selected from red, orange,
yellow, green, blue and purple pigments in such a manner as to yield a color of
low lightness, particularly achromatic black, by additive mixture in a weather
resistant vehicle and a structure covered with said coating composition. The heat
shielding coating composition is capable of covering the outside of said structure
exposed directly to the sun and suppressing a rise in the inside temperature. Such
selected composition shows a certain IR reflection and can be used for solar heat
shielding. The use of C.I. Pigment Violet 29, a perylenetetracarboxylic acid diimide
as a pigment component for such an application is not mentioned.
European Patent Application No.23,318 describes a gray to black colored
thermoplastic film for laminated identity cards, containing a white pigment and/or
filler and a gray mixture of colored organic pigments. Preferred materials are
(A) antimony oxide, kaolin, silica, chalk, barium sulfate, titanium dioxide and
zinc sulfide; (B) mixtures of red and green pigments in 6-12:10 weight ratio; violet
and green in 5-15:10 weight ratio; and violet, yellow and blue in 20:30:10 to 50:60:10
weight ratio.
Copending U.S. patent application No. 60/367,180, published as WO03/080741,
describes a black co-milled pigment composition comprising a mixture of from 2
to 98 parts by weight of a green halogenated copper phthalocyanine pigment and
from 2 to 98 parts by weight of at least one second organic pigment that is not
a green halogenated copper phthalocyanine pigment, and which pigment composition
has a specific surface area below 50 m
2/g. Such pigment compositions
are different from those of the present invention. However, they have the disadvantage
that a milling step is needed for their preparation. Additionally, they show different
color shades when diluted with white, metallic or effect pigments.
The present invention relates to the surprising discovery that selected blends
of a halogenated copper phthalocyanine with C.I. Pigment Violet 29, a perylenetetra-carboxylic
acid diimide are black in masstone and can generate IR reflective colorations when
applied in coatings, inks or plastics, and in particular, when applied together
with effect pigments such as pearlescent mica.
BRIEF DESCRIPTION OF THE DRAWINGS
The IR reflective data are obtained utilizing a Varian Cary 500 IR spectrophotometer
equipped with a reflectance Labsphere attachment.
FIG. 1 shows the IR reflection spectrum of inventive black pigment composition
prepared according to Example 1, comprising 50 percent by weight of C.I. Pigment
Green 7 and 50% percent by weight of C.I. Pigment Violet 29.
FIG. 2 IR shows the reflection spectrum of inventive pigment composition prepared
according to Example 1 when applied in an automotive paint in a mixture with Russet
mica (Afflair Pigment 9504 SW Red from the MEARL Corporation).
FIG. 3 IR shows the reflection spectrum of inventive black composition prepared
according to Example 1 in an automotive paint in a mixture with White Mica.
FIG. 4 shows the IR reflection spectrum of the carbon black of example 4B.
FIG. 5 shows the IR reflection spectrum of carbon black of example 4B with Russet Mica.
FIG. 6 shows the IR reflection spectrum of carbon black of example 4B with White Mica.
DETAILED DESCRIPTION
The present invention relates to a pigment composition, which comprises from
20 to 80 parts by weight of a halogenated copper phthalocyanine of the formula
I
##STR1##
wherein X is chlorine and/or bromine and n is a number from 1 to 4, and 20
to 80 parts by weight of C.I. Pigment Violet 29, a perylenetetracarboxylic acid
diimide of formula II
##STR2##
wherein the parts by weight of the halogenated copper phthalocyanine of formula
(I) and the perylenetetracarboxylic acid diimide of formula (II) total 100 parts
by weight, and which composition is characterized by an IR reflection spectrum
with a positive slope in the wavelength range between 800 and 900 nm when incorporated
as a coloring agent in coatings or plastics.
Preferably, the IR reflective pigment composition comprises from about
25 to 70 parts by weight of the halogenated copper phthalocyanine of formula (I)
and about 30 to 75 parts by weight of the perylene-tetracarboxylic acid diimide
of formula (II), most preferably from about 35 to 65 parts by weight of the C.I.
Pigment Green 7 as the halogenated copper phthalocyanine of formula (I) and from
about 35 to 65 parts by weight of the C.I. Pigment Violet 29 as the perylene-tetracarboxylic
acid diimide of formula (I); in each instance the sum of the parts by weight of
the corresponding pigment components is 100.
Preferably, the IR reflective pigment composition comprises green halogenated
copper phthalocyanine pigments such as the chlorinated copper phthalocyanine, C.I.
Pigment Green 7 and the brominated copper phthalocyanine, C.I. Pigment Green 36.
It is most preferred that the IR reflective pigment composition comprises C.I.
Pigment Green 7 as the halogenated copper phthalocyanine pigment of formula (I).
The inventive pigment compositions show outstanding pigment properties and are
ideally suited for use as IR reflective compositions. Surprisingly, when incorporated
into mixtures with effect pigments, such as pearlescent mica, the compositions
are black with only a slightly bluish or reddish color flop, depending on the kind
of pearlescent pigment, and show enhanced IR reflection. Therefore, besides their
IR reflective properties, such compositions have unique color properties and due
to their distinctive black color, offer new styling opportunities.
C.I. Pigment Violet 29 is a well known and commercially available perylenetetracarboxylic
acid diimide pigment. Although a large or medium particle size perylenetetracarboxylic
acid diimide pigment with a specific surface area in the range of 10 to 40 m
2/g
can be used for the inventive IR reflective pigment composition, preferably a small
particle size pigment with a specific surface area equal to or greater than about
40 m
2/g, most preferably equal to or greater than about 50 m
2/g
is used as a component for the inventive pigment composition.
Thus, the present invention relates to a process for the preparation of new
pigment compositions which offer the possibility of creating new color shades when
applied alone or in mixture with other organic, inorganic or effect pigments, and
which have the additional advantage of being IR reflective.
In order to measure the reflection spectrum, the inventive pigment is first incorporated
into a substrate such as the basecoat/clearcoat paint system described in Example
4A. The reflection spectrum of the pigmented substrate such as the coated panel
or a pigmented plastic sheet, is then measured. The reflection spectra are measured
at "complete hide", which means that the substrate is pigmented to such an extent
that no background color is observable. At "complete hide" it is not possible to
see the background color of a coated panel or the background color through a pigmented
plastic sheet.
The overall shape of the reflection spectra is characteristic of the inventive
pigment regardless of the substrate into which the pigment is incorporated. However,
the percent reflectance at any particular wavelength will vary depending on the substrate.
Appropriate substrates include lacquers, inks, coating compositions,
and plastics. Especially appropriate coating compositions include the basecoat/clearcoat
systems conventionally used in the automotive industry. Especially appropriate
plastics include the polyvinyl halides, especially polyvinyl chloride, and polyolefins,
for example low or linear low density or high density polyethylene and polypropylene.
A masstone reflectance spectrum is the reflectance spectrum observed when the
inventive
pigment is the only pigment used to color the substrate.
Basecoat/clearcoat coating systems, such as those used in the
automotive industry, are important substrates for the inventive pigment composition.
When incorporated into a basecoat/clearcoat paint system at complete hide in a
masstone color shade, the halogenated copper phthalocyanine, C.I. Pigment Green
7 shows a small reflection peak in the visible range at 500 nm and IR reflection
starting with a positive slope at 800 nm reaching around 15 to 18% in the wavelength
range of 950 to 2500 nm. The masstone base coat clear coat panel of C.I. Pigment
Violet 29 shows a reflection of only 4 to 5% in the wavelength range of 400 to
600 nm, starting with a positive slope at 630 nm, reaching a reflection of only
11.5% at 1000 nm. Surprisingly, the inventive black pigment composition prepared
according to present Example 1, comprising 50 percent by weight of C.I. Pigment
Green 7 and 50% percent by weight of C.I. Pigment Violet 29 shows no reflection
peak at 500 nm, a reflection of only 5 to 6% in the visible range from 400 to 650
nm, following by a positive slope between 800 to 900 nm and reaching a maximum
of around 20% reflection at 950-1000 nm (see FIG. 1).
Unexpectedly, the inventive compositions display a strong IR reflection
in the range of 700 to 2000 nm when incorporated with commercially available pearlescent
mica pigments as described more explicitly in the following patent examples. For
example the inventive pigment composition prepared according to Example 1 shows
a strong IR reflection of above 50% in the wavelength range of 1000 to 1400 nm
when applied in an automotive paint in a 1:1 mixture with Russet mica (Afflair
Pigment 9504 SW Red from the MEARL Corporation, see FIG. 2).
In comparison to other known IR reflective pigments, like inorganic C.I. Pigment
Black 15 or C.I. Pigment Green 17, the inventive pigment composition mixtures with
pearlescent mica show a favorable reflection spectrum with a steeper positive slope
in the wavelength range of 700 to 1000 nm.
Additionally, the inventive pigment composition show a black let down
color when incorporated with pearlescent micas. The darkness of this coloration
is comparable to carbon black let down with the corresponding mica pigments. However,
such carbon black/pearlescent mica mixtures show as little IR reflection in the
range of 700 to 2500 nm as carbon black itself (see FIGS. 4 to 6).
By simply co-blending a green halogenated copper phthalocyanine with C.I. Pigment
Violet 29, the inventive IR reflective pigment compositions are prepared. Thus,
no expensive and time consuming kneading or milling process is needed. However,
the inventive IR reflective pigment compositions can also be prepared by a dry
or wet milling process in the presence of additives. It is preferred that the inventive
IR reflective black pigment composition is preparted by co-blending, optionally
in the presence of additives, by a dry or wet milling process. It is even more
preferred that the inventive IR reflective black pigment composition is prepared
by co-blending by a dry blending process. As illustrated in the accompanying examples,
a masstone formulation generally produces a strong black coating. Such black pigments
are ideal adjunct-effect pigments when applied with effect pigments and therefore
beneficial for shading applications.
The preparation of the green halogenated copper phthalocyanines, for example
C.I. Pigment Green 7, the chlorinated copper phthalocyanine, is well known in the
industry and several pigment producers market it. A particular interesting form
for the current invention is IRGALITE Green 2180, from Ciba Specialty Chemicals,
a small particle size C.I. Pigment Green 7 with an average pigment particle size
of below 0.2 μm as measured by an electron micrograph.
The inventive pigment mixtures are prepared by mixing aqueous slurries of the
corresponding pigment components in their desired ratio. Preferably they are co-blended
in their dry powder forms, optionally in the presence of additives, in any suitable
equipment such as a closed container, which is rolled on a roller gear or shaken
on a shaker. Suitable blenders are also the TURBULA mixer from W. Bachofen, Basel,
Switzerland, or the P-K TWIN-SHELL INTENSIFIER BLENDER from Patterson-Kelley Division,
East Stroudsburg, Pa., or other vertical or horizontal commercially available blenders.
Thus, the inventive pigment compositions can be prepared in an environmentally
friendly, economical process in available equipment and with a high throughput.
Preferably, the method for preparing an inventive IR reflective black
pigment composition comprises co-blending dry pigment powders of the halogenated
copper phthalocyanine and the perylene tetracarboxylic acid diimide, optionally
in the presence of additives, in a horizontal or vertical blender.
In order to further improve the properties of the inventive pigment composition,
the mixture is co-blended in the presence of an additive selected from the group
consisting of texture-improving agents, anti-flocculating agents, rheology improving
agents or extenders and mixtures thereof. The additive or additives are optionally
added before, during or after the blending process.
The texture-improving agent, anti-flocculant, rheology improving agent and/or
extender is preferably incorporated into the present pigment compositions in an
amount of from 0.05 to 30 percent, most preferably 0.5 to 25 percent, by weight,
based on the combined weights of the pigment mixture.
Texture-improving agents are especially useful as an additional
component, which improves the properties of the black pigment composition. Suitable
texture-improving agents include fatty acids having at least 12 carbon atoms, and
amides, esters or salts of fatty acids. Typical fatty acid derived texture-improving
agents include fatty acids such as stearic acid or behenic acid, and fatty amines
like lauryl amine, or stearylamine. In addition, fatty alcohols or ethoxylated
fatty alcohols, diols like aliphatic 1,2-diols such as 1,2-dodecanediol or polyols
like polyvinylalcohol and epoxidized soy bean oil, waxes, resin acids and resin
acid salts are suitable texture-improving agents. Rosin acids and rosin acid salts
are especially suitable texture-improving agents.
Anti-flocculating agents, which can also act as rheology improving
agents, for example copper phthalocyanine derivative, quinacridone- or dihydroquinacridone
derivatives, are known in the pigment industry. Preferably, the additive is quinacridone
monosulfonic acid or quinacridone monosulfonic acid aluminum salt or 3,5-dimethylpyrazol-1-methyl
quinacridone or a mixture thereof.
Generally, the inventive IR reflective pigment composition is characterized
as having a chroma C* as measured by C.I.E. color space values in masstone of less
than 3, preferably less than 2.5 as measured on a panel coated with an acrylic
or polyester enamel coating of dry film thickness of 35±10 μm and a
pigment to binder weight ratio of 0.5.
Typically, the pigments in the inventive black IR reflective pigment composition
have a particle size of below 10 microns, most preferably in the range of 0.001
to 3 microns, and most preferably 0.002 to 0.2 microns.
Unexpectedly, the inventive pigment mixtures show characteristic absorption
and reflection in the visible and IR wavelength range and unique color characteristics
when incorporated into high molecular weight substrates.
The inventive pigment compositions of this invention are suitable for use as
pigments for coloring a solid or liquid substrate, preferably a high molecular
weight organic material.
Examples of high molecular weight organic materials which may be colored
or pigmented with the inventive black pigment compositions are cellulose ethers
and esters such as ethyl cellulose, nitrocellulose, cellulose acetate, cellulose
butyrate, natural resins or synthetic resins such as polymerization resins or condensation
resins, for example aminoplasts, in particular urea/formaldehyde and melamine/formaldehyde
resins, alkyd resins, phenolic plastics, polycarbonates, polyolefins, polystyrene,
polyvinyl chloride, polyamides, polyurethanes, polyesters, rubber, casein, silicone
and silicone resins, singly or in mixtures. Preferably, the high molecular weight
materials have a molecular weight in the range of from 10
3 to 10
8 g/mol.
Preferably, the high molecular weight organic material is an industrial
or automotive paint, an ink, a security ink, a powder or a UV/EB cured coating system.
The above high molecular weight organic materials may be singly or as mixtures
in the form of plastics, melts or of spinning solutions, varnishes, paints or printing
inks. The inventive pigment compositions are preferably employed in an amount of
0.1 to 30 percent by weight, based on the high molecular organic material to be pigmented.
The pigmenting of the high molecular weight organic materials with the black
pigment compositions of the invention is carried out for example by incorporating
such a composition, optionally in the form of a masterbatch, into the substrates
using roll mills, mixing or grinding machines. The pigmented material is then brought
into the desired final form by methods which are known per se, for example calendering,
molding, extruding, coating, spinning, casting or by injection molding. It is often
desirable to incorporate plasticizers into the high molecular weight compounds
before processing in order to produce non-brittle moldings or to diminish their
brittleness. Suitable plasticizers are for example esters of phosphoric acid, phthalic
acid or sebacic acid. The plasticizers may be incorporated before or after working
the composition into the polymers.
The inventive pigment compositions are suitable as colorants in powders and powder
coating materials, especially in triboelectrically or electrokinetically sprayable
powder coating materials which are used to coat the surfaces of articles made,
for example, from metal, wood, plastic, glass, ceramic, concrete, textile material,
paper or rubber. As powder coating resins it is typical to use epoxy resins, carboxyl-
and hydroxyl-containing polyester resins, polyurethane resins and acrylic resins
together with customary hardeners. Resin combinations are also used. For example,
epoxy resins are frequently used in combination with carboxyl- and hydroxyl-containing
polyester resins. Examples of typical hardener components (depending on the resin
system) are acid anhydrides, imidazoles and also dicyandiamide and its derivatives,
blocked isocyanates, bisacylurethanes, phenolic resins and melamine resins, triglycidyl
isocyanurates, oxazolines and dicarboxylic acids.
Furthermore, the inventive pigment compositions are suitable as colorants
in inkjet inks on an aqueous and nonaqueous basis and also in those inks that operate
in accordance with the hot-melt process.
Such printing inks are, for example, a liquid or paste-form dispersion that
comprises pigments, binders and also optionally solvents and/or optionally water
and additives. In a liquid printing ink, the binder and, if applicable, the additives
are generally dissolved in a solvent. Customary viscosities in the Brookfield viscometer
are, for example, from 20 to 5000 mPa.s, for example from 20 to 1000 mPa.s, for
liquid printing inks. For paste-form printing inks, the values range, for example,
from 1 to 100 Pa.s, preferably from 5 to 50 Pa·s. The person skilled in the
art will be familiar with the ingredients and compositions of printing inks.
Suitable pigments, like the printing ink formulations customary in the art,
are generally known and widely described.
Printing inks comprise pigments advantageously in a concentration of, for
example, from 0.01 to 40% by weight, preferably from 1 to 25% by weight, especially
from 5 to 10% by weight, based on the total weight of the printing ink.
The printing inks can be used, for example, for intaglio printing, flexographic
printing, screen printing, offset printing, lithography or continuous or dropwise
ink-jet printing on material pretreated in accordance with the process of the invention
using generally known formulations, for example in publishing, packaging or shipping,
in logistics, in advertising, in security printing or in the field of office equipment.
Suitable printing inks are both solvent-based printing inks and water-based
printing inks. Of interest are, for example, printing inks based on aqueous acrylate.
Such inks are to be understood as including polymers or copolymers that are obtained
by polymerisation of at least one monomer containing a group
##STR3##
and that are dissolved in water or a water-containing organic solvent.
Suitable organic solvents are water-miscible solvents customarily used by
the person skilled in the art, for example alcohols, such as methanol, ethanol
and isomers of propanol, for example isopropanol, butanol and pentanol, ethylene
glycol and ethers thereof, such as ethylene glycol methyl ether and ethylene glycol
ethyl ether, and ketones, such as acetone, ethyl methyl ketone or cyclohexanone.
Water and alcohols are preferred.
Suitable printing inks comprise, for example, as binder primarily an acrylate
polymer or copolymer and the solvent is selected, for example, from the group consisting
of water, C
1-C
5alcohols, ethylene glycol, 2-(C
1-C
5alkoxy)-ethanol,
acetone, ethyl methyl ketone and any mixtures thereof.
In addition to the binder, the printing inks may also comprise customary additives
known to the person skilled in the art in customary concentrations.
For intaglio or flexographic printing, a printing ink is usually prepared by
dilution of a printing ink concentrate and can then be used in accordance with
methods known per se. The printing inks may, for example, also comprise alkyd systems
that dry oxidatively.
The printing inks are dried in a known manner customary in the art, optionally
with heating of the coating.
A suitable aqueous printing ink composition comprises, for example, a pigment
or
a combination of pigments, a dispersant and a binder.
Dispersants that come into consideration include, for example, customary
dispersants, such as water-soluble dispersants based on one or more arylsulfonic
acid/formaldehyde condensation products or on one or more water-soluble oxalkylated
phenols, non-ionic dispersants or polymeric acids.
The arylsulfonic acid/formaldehyde condensation products are obtainable, for
example, by sulfonation of aromatic compounds, such as naphthalene itself or naphthalene-containing
mixtures, and subsequent condensation of the resulting arylsulfonic acids with
formaldehyde. Such dispersants are known and are described, for example, in U.S.
Pat. No. 5,186,846 und DE-A-19727767. Suitable oxalkylated phenols are likewise
known and are described, for example, in U.S. Pat. No. 4,218,218 und DE-A-19727767.
Suitable non-ionic dispersants are, for example, alkylene oxide adducts, polymerisation
products of vinylpyrrolidone, vinyl acetate or vinyl alcohol and co- or ter-polymers
of vinyl pyrrolidone with vinyl acetate and/or vinyl alcohol.
It is also possible, for example, to use polymeric acids which act both as dispersants
and as binders. Examples of suitable binder components that may be mentioned include
acrylate-group-containing, vinyl-group-containing and/or epoxy-group-containing
monomers, prepolymers and polymers and mixtures thereof. Further examples are melamine
acrylates and silicone acrylates. The acrylate compounds may also be non-ionically
modified (e.g. provided with amino groups) or ionically modified (e.g. provided
with acid groups or ammonium groups) and used in the form of aqueous dispersions
or emulsions (e.g. EP-A-704 469, EP-A-12 339). Furthermore, in order to obtain
the desired viscosity, the solventless acrylate polymers can be mixed with so-called
reactive diluents, for example vinyl-group-containing monomers. Further suitable
binder components are epoxy-group-containing compounds.
The printing ink compositions may also comprise as additional component, for
example, an agent having a water-retaining action (humectant), e.g. polyhydric
alcohols, polyalkylene glycols, which renders the compositions especially suitable
for ink-jet printing.
It will be understood that the printing inks may comprise further auxiliaries,
such as are customary especially for (aqueous) ink-jet inks and in the printing
and coating industries, for example preservatives (such as glutardialdehyde and/or
tetramethylolacetyleneurea, anti-oxidants, degassers/defoamers, viscosity regulators,
flow improvers, anti-settling agents, gloss improvers, lubricants, adhesion promoters,
anti-skin agents, matting agents, emulsifiers, stabilisers, hydrophobic agents,
light stabilisers, handle improvers and anti-statics. When such agents are present
in the compositions, their total amount is generally ≦1% by weight, based
on the weight of the preparation.
It is also possible for the printing inks to comprise buffer substances, for
example
borax, borate, phosphate, polyphosphate or citrate, in amounts of e.g. from 0.1
to 3% by weight, in order to establish a pH value of e.g. from 4 to 9, especially
from 5 to 8.5.
As further additives, such printing inks may comprise surfactants or humectants.
Surfactants that come into consideration include commercially available anionic
and non-ionic surfactants. Humectants that come into consideration include, for
example, urea or a mixture of sodium lactate (advantageously in the form of a 50
to 60% aqueous solution) and glycerol and/or propylene glycol in amounts of e.g.
from 0.1 to 30% by weight, especially from 2 to 30% by weight, in the printing inks.
Furthermore, the printing inks may also comprise customary additives,
for example foam-reducing agents or especially substances that inhibit the growth
of fungi and/or bacteria. Such additives are usually used in amounts of from 0.01
to 1% by weight, based on the total weight of the printing ink.
The printing inks may also be prepared in a customary manner by mixing the individual
components together, for example in the desired amount of water.
As already mentioned, depending upon the nature of the use, it may be necessary
for e.g. the viscosity or other physical properties of the printing ink, especially
those properties which influence the affinity of the printing ink for the substrate
in question, to be adapted accordingly.
The printing inks are also suitable, for example, for use in recording systems
of the kind in which a printing ink is expressed from a small opening in the form
of droplets which are directed towards a substrate on which an image is formed.
Suitable substrates are, for example, textile fibre materials, paper, plastics
or aluminium foils pretreated by the process according to the invention. Suitable
recording systems are e.g. commercially available ink-jet printers.
Preference is given to printing processes in which aqueous printing inks
are used.
The inventive pigment compositions are also suitable as colorants for color filters,
both for additive and for subtractive color generation.
The inventive pigment compositions are distinguished by outstanding coloristic
and Theological properties, high color strength, ease of dispersibility, high thermostability,
e.g. in plastic applications, and high transparency, e.g. in paint and ink applications.
To obtain different shades, it is also possible to add inorganic or polymeric
fillers or other chromophoric components such as organic or inorganic pigments
like white, colored, effect, fluorescent or phosphorescent pigments, in any amount,
to the high molecular weight organic compounds, in addition to the pigment compositions
of this invention.
Especially suitable classes of effect pigments which can be advantageously
used in combination with the inventive pigment compositions are selected from the
group of metallic pigments like aluminum, gold, brass or copper pigments, including
metal oxide coated metal pigments such as iron oxide coated aluminum as described
in published European Patent 33457, platelike graphite or molybdenum disulfide
pigments such as those described in U.S. Pat. Nos. 4,517,320; 5,034,430; large
particle size organic pigments such as those described in U.S. Pat. Nos. 5,084,573;
5,095,122; 5,298,076 and 5,347,014; the well known coated flaky mica, synthetic
aluminum oxide or silicon dioxide pigments, wherein the coating can be single or
multi layered and consists of colorless, chromatic or black microcrystalline compounds
such as TiO
2, SnO
2, ZrO
2, FeOOH, Fe
2O
3,
Cr
2O
3, CrPO
4, KFe[Fe
9CN)
6,
TiO
2-x, Fe
3O
4, FeTiO
3 TiN and TiO,
and the more recent classes of effect pigments, for example, the multilayer interference
platelets disclosed in PCT International Applications WO 95-17,480 and WO.95-29,140,
or the liquid crystal interference pigments described for example in German patent 4,418,075.
Such effect pigments can be incorporated in mixture with the inventive pigment
composition when incorporated into a substrate or can be co-blended as powder before,
during or after the preparation of the inventive pigment compositions.
For example, the inventive black pigment can be combined with an effect pigment.
The weight of the IR reflective black pigment in the resulting pigment mixture
is between about 90 to 10 percent, preferably between about 80 to 20 percent and
most preferably between about 75 to 25 percent based on the total weight of the mixture.
In the case where pearlescent mica is combined with the inventive black pigment,
the pearlescent mica/inventive black pigment mixture shows a very high IR reflection.
Although the new inventive pigment compositions show good light and heat
stability, it can be advantageous to apply the present compositions in the presence
of commonly known and commercially available antioxidants, UV absorbers, light
stabilizers, processing agents and so forth.
For pigmenting coatings, varnishes and printing inks, the high molecular weight
organic materials and the inventive pigmentary compositions, together with optional
additives such as fillers, other pigments, siccatives, light- or UV-stabilizers,
are finely dispersed in a common organic solvent or mixture of solvents including
water. The procedure may be such that the individual components by themselves,
or several jointly, are dispersed or dissolved in the solvent and subsequently
all the components are mixed.
The inventive black IR reflective pigment compositions, in comparison to carbon
black, have considerably better rheological properties, and are particularly suitable
for preparing aqueous and solvent based coatings conventionally employed in the
automobile industry, especially in acrylic/melamine resin, alkyd/melamine resin
or thermoplastic acrylic resin systems, as well as in powder coatings and UV/EB
cured coating systems.
An inventive pigment composition with especially good rheological properties
is
obtained when the corresponding pigment components are co-blended with additives
wherein the additive is quinacridone monosulfonic acid or quinacridone monosulfonic
acid aluminum salt or 3,5-dimethyl pyrazol-1-methyl quinacridone, or mixtures thereof.
Such co-blended pigment mixtures can show excellent rheological properties when
applied in automotive and industrial paints.
Coatings and ink systems colored with the inventive pigment compositions
possess a high gloss, excellent heat, light and weather fastness, as well as bleed
and over spraying fastness properties.
Due to their outstanding heat stability and nonabrasiveness, the inventive pigment
compositions are particularly appropriate for coloring thermoplastics including
polypropylene, polyethylene, soft, medium hard and hard polyvinyl chloride, ABS,
PES and nylon. For example in soft and medium hard polyvinyl chloride, very attractive
black, migration resistant colorations can be prepared.
The colorations obtained in plastics and filaments show unique reflection spectra
and, have good all-round fastness properties such as high migration resistance,
heat and light stability and weathering behavior.
Generally, the inventive black pigment compositions, when applied at a
pigment concentration of 0.5 percent in high-density polyethylene and molded at
200° C., show a reflection of 4 to 7 percent, preferably 4 to 6 percent in
the region of 400 to 700 nm.
The black pigment compositions of this invention are also suitable for use as
colorants for paper, including security paper, leather, inorganic materials, seeds,
and in cosmetics.
The following examples illustrate various embodiments of the invention, but the
scope of the invention is not limited thereto. In the examples, all parts are by
weight unless otherwise indicated. The coloristic data are obtained utilizing a
CS-5 CHROMA SENSOR spectrophotometer. The IR reflective data are obtained utilizing
a Varian Cary 500 IR spectrophotometer equipped with a reflectance Labsphere attachment.
The color measurements were carried out in a large area view with a spectral
component included using a ACS Colorimeter Program on an ACS, CS-5 Chromasensor
from Applied Color Systems, Inc. and distributed by DATA COLOR International.
EXAMPLES
Example 1
A flask is charged with 20 g Perrindo Violet V-4050, a C.I. Pigment Violet 29
from
BAYER and 20 g IRGAZIIN Green 2180, a C.I.Pigment Green 7 from CIBA Specialty Chemicals.
The flask is closed tight and its contents are mixed for 2 hours by rolling the
flask on a rolling gear at a rotation speed of 115 feet/minute, yielding a greenish
black powder.
By rubout according to ASTM method D-387-60 in a lithographic varnish, the pigmentary
composition shows a strong black masstone color.
Example 2
The procedure of Example 1 is repeated, using instead of 20 g Perrindo Violet
V-4050, 20 g IRGAZIN Violet 9029, a C.I. Pigment Violet 29 from CIBA Specialty
Chemicals, yielding a greenish black powder and a strong black masstone color when
rubbed out according to ASTM method D-387-60.
Example 3
The procedure of Example 2 is repeated, using instead of 20 g, 30 g IRGAZIN Violet
9029, yielding a greenish black powder, which shows a strong black masstone color
when rubbed out according to ASTM method D-387-60.
Example 4A
This example shows the incorporation of the inventive pigment black into an
automotive solvent-based paint system.
Mill Base Formulation
A pint jar is charged with 40.5 grams high solids acrylic copolymer resin (68%
solids) from DUPONT, 8.84 grams acrylic A-B dispersant resin consisting of (55%
solids) from DUPONT, and 69.46 grams Solvesso 100, primarily a mixture of aromatic
solvents from American Chemical. 16.2 grams black pigment composition of Example
1 and 240 grams of glass beads are added. The mixture in the jar is shaken on a
Skandex shaker (manufactured by IDEX Corp.) for 1 hour. The black "mill base" contains
12.0% pigment with a pigment/binder ratio of 0.5 and a solids content of 30%.
Masstone Color for Spraying a Panel
70.9 grams of the above millbase, 40.8 grams of a polyester acrylic urethane
based solution 47.8% solids, 18.3 grams of a melamine resin based solution (both
solutions are from DU PONT) are mixed and diluted with a solvent mixture comprising
76 parts xylene, 21 parts butanol and 3 parts methanol to a spray viscosity of
20-22 seconds as measured by a #2 Fisher Cup.
The resin/pigment dispersion is sprayed onto a panel twice at 1½-minute
intervals as basecoat. After 2 minutes, the clearcoat resin is sprayed twice at
1½-minute intervals onto the basecoat. The sprayed panel is then flashed with
air in a flash cabinet for 10 minutes and then "baked" in an oven at 265°
F. (120 ° C.) for 30 minutes, yielding a black colored panel.
Russet Mica Dispersion
The following ingredients are stirred together to provide a mica dispersion containing
27.9% pearlescent mica pigment and a total solid content of 69.1% solids:
154.8 grams of bright russet Mica, EXTERIOR MEARLIN SUPER RUSSET 459Z from
The Mearl Corp.,
295 grams of non-aqueous dispersion resin, and
104.4 grams of acrylo urethane resin.
Russet Mica Color for Spraying Paint
A 50/50 russet mica shade coating (for 25% pigment loading) is prepared by mixing
the following ingredients:
43.2 grams of the black "mill base" dispersion
15.4 grams of "russet mica dispersion"
45.4 grams of a polyester acrylic urethane based solution
16.1 grams of a melamine based solution
The black pigment/pearlescent mica/resin dispersion, which has excellent rheological
properties, is sprayed onto a primed panel 8 times (for complete hiding) at 1-minute
intervals as basecoat. After 3 minutes, clear coat resin is sprayed twice at 1-minute
intervals onto the basecoat. The sprayed panel is flashed with air in a flash cabinet
for 10 minutes and then "baked" in an oven at 265° F. (130° C.) A black
colored effect coating with excellent weatherability is obtained. The coating shows
high gloss and a black color.
White Mica Dispersion
The following ingredients are stirred together to provide a mica dispersion containing
27.9% pearlescent mica pigment and a total solid content of 69.1% solids:
154.8 grams of bright russet mica, EXTERIOR MEARLIN BRIGHT WHITE 139X from
The Mearl Corp.,
295 grams of non-aqueous dispersion resin, and
104.4 grams of acrylo urethane resin.
White Mica Color for Spraying Paint
A 50/50 russet mica shade coating (for 25% pigment loading) is prepared by mixing
the following ingredients:
43.2 grams of the black "mill base" dispersion
15.4 grams of "White mica dispersion"
45.4 grams of a polyester acrylic urethane based solution
16.1 grams of a melamine based solution
The black pigment/pearlescent mica/resin dispersion, which has excellent rheological
properties, is sprayed onto a primed panel 8 times (for complete hiding) at 1-minute
intervals as basecoat. After 3 minutes, clear coat resin is sprayed twice at 1-minute
intervals onto the basecoat. The sprayed panel is flashed with air in a flash cabinet
for 10 minutes and then "baked" in an oven at 265° F. (130° C.). A black
colored effect coating with excellent weatherability is obtained. The coating shows
high gloss and a black color with a bluish hue.
Example 4B
Example 4B is a comparative Example. The procedures of the preparation of
a masstone, a russet mica and white mica panel are repeated using instead of 16.2
grams black pigment composition of Example 1, 16.2 grams Color Black FW 200, a
C.I. Pigment Black 7 from DEGUSSA yielding a black masstone, a black russet mica
and a black white mica coated panel.
Color Measurement
The following color characteristic data are measured on the coated panels, demonstrating
the surprising black low chroma masstone and let down colors with the pearlescent
mica by using the inventive pigment mixture.
C.I.E. L*, C*, h color space value numbers using a D65 illuminant and 10 degree
observer with a specular component included:
| |
Inventive Black |
26.3 |
1.5 |
305 |
| |
according to |
| |
Example 4A |
| |
Carbon Black |
25.8 |
0.8 |
261.9 |
| |
according to |
| |
Example 4B |
| |
Inventive Black |
28.9 |
2.7 |
359.6 |
| |
according to |
| |
Example 4A |
| |
Carbon Black |
27.9 |
3.8 |
326.8 |
| |
according to |
| |
Example 4B |
| |
Inventive Black |
28.7 |
3.5 |
287.7 |
| |
according to |
| |
Example 4A |
| |
Carbon Black |
29.0 |
0.2 |
93.4 |
| |
according to |
| |
Example 4B |
| |
|
The above readings of the inventive IR reflective black pigment show a low lightness
and low chroma in the range of carbon black.
IR Reflective Measurements
The panels prepared as described in the Examples 4A and 4B were measured on a
Varian Cary 500 IR spectrophotometer manufactured by Varian equipped with a reflectance
Labsphere attachment. The reflection spectra are displayed in FIG. 1 to FIG. 6.
They show IR reflection in the wavelength range of 700 to 2500 nm for the coatings
containing the inventive samples (FIG. 1 masstone, FIG. 2 inventive black in conjunction
with Russet Mica and FIG. 3 in conjunction with White Mica) but very little IR
reflection for carbon black and the corresponding pearlescent mica let downs (FIG.
4 masstone, FIG. 5 carbon Black/Russet Mica, FIG. 6 carbon black/White Mica).
Example 5
63.0 grams of polyvinyl chloride, 3.0 grams epoxidized soy bean oil, PARAPLEX
G-62 from the C.P. Hall Company, 2.0 grams of barium/cadmium heat stabilizer, 32.0
grams dioctyl phthalate and 1.0 gram of the black pigment composition prepared
according to Example 2 are mixed together in a glass beaker using a stirring rod.
The mixture is formed into a soft PVC sheet with a thickness of about 0.4 mm by
rolling for 8 minutes on a two roll laboratory mill at a temperature of 160°
C, a roller speed of 25 rpm and friction of 1:1.2, by constant folding, removal
and feeding. The resulting soft PVC sheet is colored in an attractive black shade
and has excellent fastness to heat, light and migration.
Example 6
Five grams of the black pigment composition prepared according to Example 3,
2.65 grams CHIMASORB 944LD (hindered amine light stabilizer), 1.0 gram TINUVIN
328 (hydroxylphenyl benzotriazole UV absorber) and 2.0 grams IRGANOX B-215 Blend
(blend of phosphite and hindered phenolic anti-oxidants), all available from Ciba
Specialty Chemicals, are mixed together with 1000 grams of high density polyethylene
at a speed of 175-200 rpm for 30 seconds after flux. The fluxed, pigmented resin
is chopped up while warm and malleable, and then fed through a granulator. The
resulting granules are molded on an injection molder with a 5 minute dwell time
and a 30 second cycle time at a temperature of 200, 250 and 300° C. Homogeneously
colored chips, which show a black color with practically no color differences,
are obtained. They have excellent light stability.
Example 7
Five grams of the black pigment composition prepared according to Example 2
is incorporated in 100 grams of a vinyl-resin ink lacquer system by stirring the
powder in the system for 30 minutes. The resulting black ink is diluted to a pigment
concentration of 1% with 1-methoxy-2-propanol.
When the lacquer is bubble free, (after ca.1 5 minutes)—the full shade
ink applications are drawn with the KCC-automatic film applicator (speed=5) on
a polyethylene foil. Using a 100 μm bar coater.
After allowing 15 minutes to flash off at room temperature, the draw downs
are dried in the oven for 30 minutes at 40° C.
After drying the lacquer film is carefully taken off and the spectrum is recorded
with the Lamda 900 spectrometer from 1100 nm to 200 nm. The clear coat lacquer
film is the base line.
The reflection spectrum shows a reflection of below 20% between 230 to 700 nm,
a positive slope between 700 and 900 nm, reaching a reflection of above 95% at
1000 nm.
*
