Molecular sieve abstract
A molecular sieve, which contains in all, or only in some, of its
cavities colorant molecules as well as a modifier which is covalently
bound to said molecular sieve and which reduces its pore diameter,
a process for its preparation as well as its use as pigment for
coloring high molecular weight organic materials, preferably biopolymers
and plastic materials, glasses, ceramic products, for formulations
of decorative cosmetics, for the preparation of paint systems, preferably
automotive lacquers, printing inks, dispersion paints and color
filters as well as materials comprising the novel molecular sieves.
Molecular sieve claims
What is claimed is:
1. A molecular sieve, which contains colorant molecules in at least
some of its cavities as well as a modifier which is covalently bound
to said molecular sieve and which reduces its pore diameter.
2. A molecular sieve according to claim 1 which is obtained either
(a) by completely or partially filling its cavities with colorant
molecules and subsequent reaction with a modifier, or (b) by reducing
the pore diameter of a molecular sieve, which already has at least
some of its cavities filled with colorant molecules, by reaction
with a modifier.
3. A molecular sieve according to claim 1 wherein the modifier
is at least one compound selected from the group consisting of metal
halides, silicone alkoxides, carbon/tin compounds, silicon hydride
compounds, tetraalkylorthosilicates, monoalkyl-, dialkyl-, trialkyl-
and triarylchlorosilanes, disiloxanes, diborane, silicate sols,
silicate colloids and halogenated polysiloxanes.
4. A process for the preparation of a molecular sieve according
to claim 1 which comprises (a) completely or partially filling
the cavities of a molecular sieve with colorant molecules and subsequently
reducing its pore diameter by reaction with a modifier, or (b) reducing
the pore diameter of a molecular sieve, which already has at least
some of its cavities filled with colorant molecules, by reaction
with a modifier.
5. A method of coloring a high molecular weight organic or inorganic
material which comprises adding a tinctorially effective amount
of a molecular sieve according to claim 1 thereto as pigment.
6. A method according to claim 5 wherein the high molecular weight
organic material is a biopolymer or a plastic material.
7. A method according to claim 5 wherein the molecular sieve is
added as a colorant to formulate decorative cosmetics or paint systems.
8. A method according to claim 5 wherein the paint system is an
automotive lacquer, a printing ink, an ink or a dispersion paint.
9. A method according to claim 5 wherein the high molecular weight
inorganic material is a glass or a ceramic product.
10. A method according to claim 5 wherein the organic or inorganic
material is a color filter.
Molecular sieve description
The present invention relates to a molecular sieve, containing
in all, or only in some, of its cavities colorant molecules as well
as a modifier which is covalently bound to said molecular sieve
and which reduces its pore diameter.
This invention also relates to a process for the preparation of
the novel molecular sieve as well as to the use thereof as pigment
for coloring high molecular weight organic materials, preferably
biopolymers and plastic materials, glasses, ceramic products, for
formulations of decorative cosmetics, for the preparation of paint
systems, preferably automotive lacquers, printing inks, dispersion
paints and color filters as well as to materials comprising the
novel molecular sieves.
Dyes adsorbed to molecular sieves have been known for some time
(see DE-A 41 26 461 p.2 lines 5-21). The interaction between the
dyes and the molecular sieves is usually so strong that desorption
is only rarely found when the dye is heated. In suitable solvents,
on the other hand, desorption may occur, adsorbed dye molecules
being removed by leaching.
U.S. Pat. No. 4018870 describes the synthesis of silicon-containing
molecular sieves in the presence of methylene blue and acriflavine
as templates, both of which are water-soluble basic dyes. In this
so-called template synthesis, the molecular sieve is synthesised
in the presence of a compound serving as molecular template. The
templates, in the present case the dye molecules, are thus inserted
into the forming cavities of the corresponding molecular sieve.
By this principle, specific molecular sieves are accessible, depending
on the template. To obtain molecular sieves having free pores and
cavities, the organic template compounds retained in the cavities
of the molecular sieves so obtained are driven off by heating.
To overcome the drawback of leaching, DE-A 41 26 461 proposes,
in accordance with the cited U.S. document, to insert dye molecules
into the framework of the molecular sieve. DE-A 41 26 461 describes,
in particular, dye-loaded inorganic molecular sieves, a water-insoluble
organic dye being irreversibly inserted into the cavity framework
of the molecular sieve. The molecular sieves disclosed in DE-A 41
26 461 are accessible by template synthesis. The preconditions for
the irreversible insertion of the dye molecules are dye molecule
sizes of at most the size of the cavities of the molecular sieve
and larger than its free pore diameter.
Zeolites 4 (1984), p. 30-34 gives a description of the so-called
ship-in-the-bottle synthesis of cobalt phthalocyanines, nickel phthalocyanines
and copper phthalocyanines (Pc) in the faujasite zeolite. In this
method, the cations present in the zeolite are first exchanged for
the cited transition metal cations. In a subsequent step, the corresponding
Pc complex is then formed inter alia in the cavities of the faujasite
by the addition of ortho-phthalodinitrile. The Pc complexes formed
in the cavities normally do not diffuse from the cavities for sterical
reasons. However, in some applications this happens unwantedly.
The molecular sieves described in DE-A 41 26 461 U.S. Pat. No.
4018870 and in Zeolites 4 (1984) have the disadvantage that the
number of possible dye-molecular sieve combinations in which dye
molecules are, or should be, irreversibly retained in the molecular
sieve, is limited by the size of the dye molecules in conjunction
with the cavity volume and free pore diameters. Moreover, in the
case of DE-A 41 26 461 amines, such as triethanolamine, must be
added as templates. However, the templates remain partly in the
molecular sieves, preventing the molecular sieve from being completely
loaded with the dye. Finally, dyes such as thioindigo are also mentioned
which, owing to their molecule size, can diffuse from the pores
of the molecular sieves.
The loading of the surface of the molecular sieves, in particular
of the pore diameter, has been repeatedly described in the literature:
In "Acid-Base Catalysis", Proceedings of the International
Symposium on Acid Base Catalysis Sapporo, (Nov. 28-Dec. 1 1988),
VCH and Kodansha, edited by Tanabe, Hattori, Yamaguchi and Tanaca,
p. 255-266 Muracami et al. describe the influence of the pore size
on the shape selectivity in crack reactions. According to the method
described by Muracami et al., the pore size changes when the zeolites
are treated with silicone alkoxides.
In Catalysis Letters 22 (1993), p.107-121 Ribeiro describes the
change of the pore diameter of zeolites with metal chlorides, such
as SiCl.sub.4 ZnCl.sub.2 GaCl.sub.3 GeCl.sub.4 TiCl.sub.4 SnCl.sub.4
and Si(OMe).sub.4 silane (SiH.sub.4), disilane (Si.sub.2 H.sub.6),
and diborane (B.sub.2 H.sub.6). He discusses, in particular, the
influence that the degree of surface loading has with respect to
the yield of para-xylene when toluene is alkylated with methanol.
Vansant et al. describe detailed research on the change of the
pore diameter in zeolites using silane and diborane (J.Chem.Soc.,
Faraday Trans. 1 198379 2821-2834) and disilane (J.Phys.Chem.
1990 94 2582-2586).
In Microporous Materials, 2 (1994) p. 251-259 Benazzi et al. describe
the pore narrowing in zeolites by treatment with different tetraalkyltin
compounds (SnR.sub.4 (R=Me, Et, i-Pr, Ph and cyclohexyl) and Bu.sub.3
SnH.
WO 92/21726 discloses pigments with combined structure, wherein
at least one layer of a water-soluble colorant is adsorbed on a
water-insoluble core material, the colorant in turn being coated
with a transparent layer. Transparent layers mentioned are materials
consisting of aluminium oxide, aluminium silicate and amorphous
silicic acid, which latter is obtainable from sodium silicate or
silica sol. The drawback of this method is, on the one hand, that
it is restricted to only water-soluble colorants and, on the other
hand, that the adhesion of the colorant by adsorption is insufficient
for many applications, in particular in case of thermal or mechanical
stress.
Accordingly, it is the object of this invention to provide colorant-loaded
molecular sieves which do not have the above disadvantages. To be
improved are, in particular, leaching, bleeding, i.e. the migration
of the colorants in plastic materials into another material in contact
with the plastic material, thermal stability, resistance to solvents,
light stability and chemical resistance, and the colorant load of
the molecular sieve should be increased.
In accordance with the above, the molecular sieve defined at the
outset was found, which contains in all, or only in some of its
cavities, colorant molecules as well as a modifier which is covalently
bound to said molecular sieve and which reduces its pore diameter.
Furthermore, there was found a process for its preparation as well
as its use as pigment for coloring high molecular weight organic
materials, preferably biopolymers and plastic materials, glasses,
ceramic products, for formulations of decorative cosmetics, for
the preparation of paint systems, preferably automotive lacquers,
printing inks, inks, dispersion paints and color filters, and also
the materials comprising the novel molecular sieve.
The novel molecular sieve contains in all, or only in some of its
cavities, colorant molecules.
In addition, the novel molecular sieve comprises a modifier which
is covalently bound to it and which reduces its pore diameter. Findings
so far have shown that the modifier preferably reacts with the functional
groups, such as OH groups, of the molecular sieve which are present
on its external surface. This also results in a reduction of the
pore diameter which may be indirectly determined by the fact that
it is possible to prepare modified molecular sieves which do not
leach and/or bleed. This can be explained by the fact that the colorant
molecules present in the cavities of a molecular sieve thus modified
cannot pass through the now narrowed pores and are therefore retained
in the cavities.
It is also possible to carry out the modification such that, for
example, not all pores are narrowed, in particular by controlling
the amount of modifier and the reaction time with the modifier.
Molecular sieves prepared in this manner can still bleed or leach
but do so to a lesser extent than unmodified molecular sieves. Depending
on the desired application, it is therefore possible to carry out
the modification such that molecular sieves are obtained which bleed
and/or leach more or less or which do not bleed and/or leach anymore
at all. It goes without saying that molecular sieves having micropores
usually require a smaller amount of modifier than mesoporous molecular
sieves.
The novel molecular sieves are obtainable (a) by completely or
partially filling their cavities with colorant molecules and subsequently
reducing their pore diameter by reaction with a modifier, or (b)
by reducing the pore diameter of a molecular sieve filled in all,
or only in some, of its cavities with colorant molecules by reaction
with a modifier.
According to findings so far, modifiers may be all those known
compounds or the mixtures thereof which are able to form covalent
bonds with the functional groups of the molecular sieve which are
present on the external surface of molecular sieves, including the
externally oriented pore openings, in particular those compounds
which are able to reduce the pore diameters of molecular sieves.
The modifier used is preferably at least one compound selected
from the group consisting of metal halides, silicon alkoxides, carbon/tin
compounds, silicon hydride compounds, tetraalkylorthosilicates,
trialkyl-, dialkyl-, monoalkyl- and triarylchlorosilanes, disiloxanes,
diborane, silicate sols and silicate colloids as well as halogenated
polysiloxanes.
Metal halides, preferably metal chlorides, may be SiCl.sub.4 ZnCl.sub.2
GaCl.sub.3 GeCl.sub.4 TiCl.sub.4 SnCl.sub.4 as described by
Ribeiro in Catalysis Letters 22 (1993), p.107-121. Silicium tetrachloride
is particularly preferred.
Silicon alkoxides may preferably be silicon tetraalkoxides, such
as Si(OR).sub.4 (with R=Me, Et, n-, i-Pr, n-, i-, sec- and tert-Bu),
particularly preferably Si(OMe).sub.4 as described by Muracami
et al. (see above).
Suitable carbon/tin compounds are, in particular, tetraalkyltin
compounds, for example SnR.sub.4 (R=Me, Et, i-Pr) and also SnPh.sub.4
and Sn(cyclohexyl).sub.4 and Bu.sub.3 SnH (described, inter alia,
by Benazzi et al. (see above).
Suitable silicon hydrides compounds are preferably silane and disilane
(see Vansant et al., mentioned above).
Tetraalkylorthosilicates may preferably be C.sub.1 -C.sub.4 tetraorthosilicates,
in particular tetraethylorthosilicate (TEOS).
It is also possible to use tri-, di- and monoalkyl- and triarylchlorosilanes,
for example ClSiR.sub.3 with R=methyl, ethyl, n-, i-Pr, n-, i-,
sec- and tert-Bu, phenyl, particularly preferably trimethylchlorosilane
and triethylchlorosilane, disiloxanes, typically hexa(C.sub.1 -C.sub.4
alkyl)disiloxanes, preferably hexamethyidisiloxane, diborane and
alkali metal silicates, for example sodium silicate and silica sol
(which latter is commercially available under the registered trade
mark LUDOX.RTM., of DuPont).
In another of its embodiments, this invention relates to a process
for the preparation of the novel molecular sieves by (a) completely
or partially filling the cavities of a molecular sieve with colorant
molecules and then narrowing its pore diameter by reaction with
a modifier, or (b) by narrowing the pore diameters of a molecular
sieve which is filled in all, or only in some, of its cavities with
colorant molecules by reaction with a modifier.
The amount of modifier to be used usually depends on the desired
objective, i.e. to what degree e.g. bleeding or leaching should
be prevented. An effective amount of modifier is therefore normally
used which may, if necessary, be determined by preliminary tests.
In a preferred embodiment of this invention, silicon-containing
modifiers are used, such as those mentioned above, and their amount
is chosen, for example, such, that the silicon content of the colorant-containing
molecular sieve is increased to the range of 3 to 60% by weight,
preferably of 10 to 50% by weight, particularly preferably of 20
to 40% by weight, based on the colorant-containing molecular sieve.
The temperature during the reaction with the modifier generally
depends on the type of modifier, on the desired speed at which the
modifier is to be applied, as well as on the desired layer thickness.
The upper limit of the temperature range is normally determined
by the heat stability of the colorant. The corresponding temperature
ranges are known from the literature (see above) and may, if required,
easily be determined by the skilled person by corresponding preliminary
tests. For instance, when using silicon tetrachloride, the temperature
is chosen from the range of 20 to 300.degree. C., preferably of
100 to 200.degree. C., and when using TEOS, the temperature is chosen
from the range of 20 to 400 preferably of 20 to 250 particularly
preferably of 50 to 150.degree. C.
The pressure used during the reaction with the modifier normally
depends on the type of modifier, the desired speed at which the
modifier is to be applied, the desired layer thickness as well as
on the method of application, i.e. in the vapour phase or liquid
phase.
When reacting the modifier in the liquid phase, the modifier is
usually contacted with the colorant-loaded molecular sieve over
a period of time in the range from 0.5h to 3 days, preferably from
0.5 to 2 days, for example by bringing the components together,
if desired in the presence of a solvent, and then stirring them.
Depending on the type of modifier, it is possible, if desired,
to follow the above treatment by a hydrolysis step, which procedure
is preferred in the case of modifiers which react with the molecular
sieve only in the presence of water, especially if the amount of
water present in the molecular sieve or in the liquid phase is not
sufficient for the entire reaction.
If the vapour phase is chosen as reaction medium, then the modifier
is normally passed over the colorant-loaded molecular sieve using
a customary inert gas, for example nitrogen, and noble gases, such
as helium, neon and argon, as carriers. If desired, it is also possible
to follow this vapour gas method by a hydrolysis step as described
above.
If desired, the molecular sieve can be dried before and/or after
applying the modifier, i.e. the water may be driven off to a desired
degree in per se customary manner.
In a particularly preferred embodiment of this invention, the reaction
is carried out using the modifier silicon tetrachloride by passing
an inert gas stream, the preferred inert gas being nitrogen, through
the silicon tetrachloride which has a temperature in the range from
-10 to 120 preferably from 0 to 60 particularly preferably from
15 to 40.degree. C. The inert gas stream saturated in this manner
is then passed over a sample of the colorant-loaded molecular sieve
which has been heated to a temperature in the range from 20 to 300
preferably from 120 to 180.degree. C. The pressure is usually chosen
from the range of typically 10 to 300 preferably of 90 to 110 kPa.
The reaction time is normally chosen from the range of 5 min to
10 h, preferably of 30 min to 5 h, particularly preferably of 1
to 3 h. The amount of the gas stream is usually chosen from the
range of 0.25 to 7.5 preferably of 0.5 to 2.5 particularly preferably
from 0.75 to 2 l/h, per g of colorant-loaded molecular sieve.
In another preferred embodiment of this invention, a colorant-loaded
molecular sieve is used which has a water content of more than zero,
the preferred water content being sufficiently high as to accelerate
the reaction of the modifier with the functional groups of the molecular
sieve, e.g. the OH groups.
According to findings to far, the success of this invention does
not rely on the choice of the colorant and of the molecular sieve.
Colorant-loaded molecular sieves are generally accessible by three
preparation methods:
(a) by treating a mixture consisting of a usually calcined molecular
sieve and a colorant, normally at elevated temperatures. The usual
precondition is that the colorant molecules and pore system of the
molecular sieves are sterically and electronically compatible.
In a particularly preferred embodiment of this invention, readily
sublimable colorants are used, in particular dyes. It is recommended
to carry out this treatment under vacuum. In this method, a mixture
consisting of dye and molecular sieve is heated to a temperature
in the range of 50 to 300.degree. C., preferably of 100 to 250.degree.
C., at a pressure of less than 100 kPa (1 bar), preferably of not
more than 5 kPa (50 mbar), particularly preferably of not more than
1 kPa (10 mbar) and, very particularly preferably, of not more than
0.1 kPa (1 mbar). The temperature is usually kept in this range
for 0.5 to 5 days, preferably for 1 to 4 days, more preferably for
2.5 to 3.5 days. After this treatment, excess dye, i.e. dye which
is not bound in the molecular sieve, can be removed by suitable
treatment, for example by extraction, in particular by Soxhlet extraction.
(b) by synthesising colorants in the presence of molecular sieves
(ship-in-the-bottle synthesis). The principle of this method has
been described in detail, inter alia, in Zeolites 4 (1984) p.30
so that further explanations may be dispensed with here. According
to this method, the size of the educt molecules is preferably chosen
such that they fit into the cavities of the molecular sieves. Subsequent
to the synthesis of the colorant in the cavities of the molecular
sieve, excess educt and colorants, in particular dyes, formed outside
of the cavities are removed by suitable treatment, typically by
washing with a solvent.
(c) by synthesising the molecular sieve in the presence of the
colorant (template synthesis). The template synthesis of molecular
sieves has been described in detail, inter alia, in U.S. Pat. No.
4018870 and DE-A 41 26 461 so that further explanations may be
dispensed with here. The template synthesis is usually carried out
by adding the colorant, in particular dyes, i.e. soluble compounds,
and usually, depending on the colorant, another template, to a conventional
molecular sieve synthesis mixture which consists, for example, of
a silicon source and, if required, of an aluminium source. This
mixture is normally subjected to hydrothermal treatment in an autoclave
at a temperature in the range from 100 to 250.degree. C. After this
treatment, unreacted educts, in particular the colorant, may be
removed from the molecular sieve in a manner known per se, for example
by washing or extracting with suitable solvents or sieves.
If desired, the molecular sieves may be dehydrated prior to loading
them with the colorant at elevated temperature and/or at reduced
pressure.
The insertion of the colorant molecules into the molecular sieve
may be confirmed by X-ray powder diffraction analysis and via the
determination of the adsorption capacity of e.g. nitrogen. The X-ray
powder diffractograms (measured at 120.degree. C.) of colorant-loaded
molecular sieves and of those not containing any colorant are normally
very similar, but they usually differ in the exact position of the
diffraction lines and in the intensities of the individual lines.
A comparison of nitrogen adsorption isotherms of colorant-loaded
molecular sieves of this invention with those of molecular sieves
not containing any colorants, or of those which are only partially
filled, shows that the micropore volume of completely loaded molecular
sieves has been reduced over that of the other molecular sieves.
Molecular sieves may be crystalline materials having a particle
size in the range of 0.5 to 100 .mu.m and having a uniform pore
structure and micro- and/or mesopores, such as zeolites and phosphates
of zeolite structure. The molecular sieves are preferably used in
the form of powders. Depending on the purpose of application, however,
it is also possible to use compact structures such as granulate,
cylinders or the like.
Zeolites are commonly known and are described in detail, inter
alia, in Chemie in unserer Zeit, 19864 p. 117-127 and in Angew.
Chem. 1975 18 p. 659-667. The zeolites are usually used in the
acid H-form or in the neutral alkali metal form. Elements other
than aluminium, including elements such as B, Ga, Fe, Cr, V, As,
Sb, Bi or Be or their combinations, may be inserted into the zeolite
latices. Silicon may be partially replaced with another tetravalent
element, for example Ge, Ti, Zr or Hf.
If the zeolites, owing to their preparation, are not obtained in
the acid H-form, but e.g. in the alkali metal or alkaline earth
metal form, then the desired H-form can be generated completely
or partially by ion exchange with, for example, ammonium ions and
subsequent calcination or by treatment with acids.
Preferred zeolites are the zeolites A, X, Y, L, ZSM-5 ZSM-11
zeolites of the mordenite group, in particular mordenite, and faujasite
type zeolites. Particularly preferred zeolites are zeolite HY, zeolite
NaY, zeolite H-mordenite and zeolite LZY-52 (of Union Carbide).
It is also possible to use mesoporous silicates or metal silicates
of MCM-41 structure as molecular sieve. Examples to be mentioned
are: amorphous mesoporous MCM-41 having an adjustable pore width
in the range of typically 3 to 10 nm (see, for example, J.of Am.Chem.
Soc. 114 (1992)10834-10843 U.S. Pat. No. 5098684 U.S. Pat. No.
5105051 U.S. Pat. No. 5134242 U.S. Pat. No. 5134243), molecular
sieves of the M41S family, such as MCM-41 of hexagonal structure,
MCM-50 of laminar structure (see Stud.Surf.Sci.Catal. 84 (1994)
53-60), MCM-48 of cubic structure (see Stud.Surf.Sci.Catal. 84 (1994)
53-60), FSM-16 (see Stud.Surf.Sci.Catal. 84 (1994) 125-132), metal
silicates having different metals M (see WO 91/11390 for M=Al, J.Chem.Soc.,
Chem. Commun. (1994) 147-148 for M=Ti, J.Chem.Soc., Chem.Commun.
(1994) 1059-1060 for M=V, and Prep.6th Int.Symp.Sci. Bases Heterog.Cat.1
(1994) 345-352 for M=W, Mo, Pb and Fe).
It is also known that it is possible to achieve a much higher Si/Al
ratio by repeated treatment with water vapour and acid than by simple
treatment with water or acid. Zeolites treated in this manner (faujasites)
have a mesoporous system, i.e. they have pores having a diameter
in the range from 2 to 50 nm (20 to 500 Angstrom). The entire volume
of this mesoporous system is mainly influenced by the original number
of Al atoms in the zeolite framework. In this case, the mesopores
produced in this manner are usually bound to the external surface
of the zeolite (Inorg.Chem. 15(2) (1976) 295-297; J.Phys.Chem. 93
(1989) 3677-3683; Zeolites 14 (1994) 533-540; Microporous Materials
6 (1996) 311-320).
The porous structure of molecular sieves, in particular of zeolites,
may be characterised by nitrogen adsorption. The volume of the microporous
system (pore diameter less than 2 nm (20 Angstrom)) is usually determined
by means of the so-called t-plot equation. The specific surface
of micro- and mesoporous solids is determined by the BET method.
The mesoporous structure may be characterised by means of the so-called
BJH model (see e.g. J.Am.Chem.Soc. 73 (1951) 373-380).
Phosphates of zeolite structure--so-called AIPOs, SAPOs, ELSAPOs,
ELAPOs, MeAPOs and ZYTs--are described in detail, inter alia, in
"Alumophosphate moleculare sieves and the periodic table"
Pure & Appl. Chem. Vol 58 No.10 p.1351 to 1358 (1986), and
in U.S. Pat. No. 4310440 (AIPO), EP-A-103117 U.S. Pat. No. 4440871
(SAPO) and J 59/217619 (ZYT).
To be mentioned as examples are AIPO-5 AIPO-8 AIPO-9 AIPO-11
AIPO-12 AIPO-14 AIPO-21 AIPO-25 AIPO-31 AIPO-33 and MCM-9.
Syntheses of these compounds are described in EP-A 132 708 U.S.
Pat. No. 4310440 and J.Am.Chem.Soc. 104 (1982) 1146. Compounds
which may be used as SAPO are SAPO-5 SAPO-8 SAPO-11 SAPO-31 and
SAPO-34. The preparation of these compounds is described in detail
in EP-A 103117 and
U.S. Pat. No. 4440871. Typical examples of other silicon aluminium
phosphates which may be used are ZYT-5 ZYT-6 ZYT-7 ZYT-9 and
ZYT-12 (see J 59 217 619).
It is also possible to use molecular sieves of VPI-5 structure
(M. E. Davis et al. J.Phys.Chem. 1991 95 p. 1380-1383), cloverite
(gallium phosphate; Nature 352 (1991) p. 320-322) and JDF-20 (J.
Chem. Soc. Chem. Commun. (1992) p. 875-876). In a preferred embodiment
of this invention, the pore size of the molecular sieves is chosen
from the range of 0.4 to 1.4 nm (4 to 14 .ANG.), preferably of 0.5
to 1.2 nm (5 to 12 .ANG.), more preferably of 0.5 to 0.8 nm (5 to
8 .ANG.). However, as described above, it is also possible to use
mesoporous zeolites having a pore size in the range of 2 to 50 nm.
The colorant may be soluble (dye) as well as insoluble (pigment)
compounds.
For practical reasons it is preferred to use compounds which may
be sublimated so that the molecular sieve can be loaded with the
colorant in the vapour phase.
Examples to be mentioned are azo pigments, for example monoazo,
diazo, naphthalene, benzimidazole, diazo condensate, metal complex,
isoindolinone and isoindoline pigments, indigo, quinophthalone pigments,
dioxazine pigments and polycyclic pigments, such as quinacridone,
phthalocyanine, perylene, perinone and thioindigo pigments and also
anthraquinone pigments, such as aminoanthraquinone, hydroxyanthraquinone,
anthrapyrimidine, indanthrone, flavanthrone, pyranthrone, anthanthrone
and isoviolanthrone pigments and diketopyrrolopyrrole (DPP) pigments.
Preferred colorants are anthraquinone, DPP, azo and indigo pigments,
typically 14-diketo-36-diarylpyrrolo-[34-c]pyrroles, particularly
preferably the soluble N,N'-dimethyl-14-diketo-36-diarylpyrrolo-[34-c]pyrroles,
such as N,N'-dimethyl-14-diketo-36-diphenylpyrrolo-[34-c]pyrrole.
In a preferred embodiment of this invention, soluble compounds
are used which are obtained by chemical modification of pigments
in per se conventional manner, e.g. by the introduction of customary
polar functional groups such as sulfonic acid groups or ammonium
groups.
The mentioned colorants are commonly known and some of them are
commercially available and/or may be prepared in analogy to known
processes.
The load of the molecular sieve with the colorant can normally
be controlled by suitable choice of the molecular sieve and/or by
the choice of the ratio of colorant to molecular sieve.
The amount of load is influenced, for example, by the type and
amount of the alkali metal ions in a molecular sieve. The insertion
of N,N'-dimethyl-14-diketo-36-diphenylpyrrolo-[34-c]-pyrrole
into zeolite LiX-90 for example, succeeds to at most 13% by weight,
into zeolite NaX-100 to at most 12% by weight, into zeolite KX-100
to at most 7% by weight, based on the weight of the corresponding
zeolite. Accordingly, zeolite LiY-65 can be loaded with the cited
colorant to at most 13% by weight, zeolite NaY-1 00 to at most 12%
by weight and zeolite KY-100 to at most 3% by weight, based on the
weight of the corresponding zeolite.
Maximum loading of zeolite NaY-100 (12% by weight) can also be
carried out, for example, using a ratio of the cited colorant N,N'-dimethyl-14-diketo-36-diphenyl-25-dihydropyrrolo-[34-c]pyrrole
to zeolite NaY-100 of 1:3 whereas loading using a ratio of e.g.
1:30 gives a maximum load of 3% by weight.
The ratio of colorant to molecular sieve is usually chosen from
the range of 0.01 to 60 preferably of 0.5 to 40 particularly preferably
of 0.5 to 35% by weight, based on the weight of the (unloaded) molecular
sieve.
The novel molecular sieves are advantageously suitable for many
purposes, such as for coloring high molecular weight organic materials
such as biopolymers, plastic materials, including fibres, glasses,
ceramic products, for formulations of decorative cosmetics, for
the preparation of inks, printing inks, paint systems, preferably
automotive lacquers, and dispersion paints.
Illustrative examples of suitable high molecular weight organic
materials which can be colored with the novel compounds are vinyl
polymers, such as polystyrene, poly-.alpha.-methylstyrene, poly-p-methylstyrene,
poly-p-hydroxystyrene, poly-p-hydroxyphenylstyrene, polymethyl methacrylate
and polyacrylamide as well as the corresponding methacrylic compounds,
polymethylmaleate, polyacrylonitrile, polymethacrylonitrile, polyvinyl
chloride, polyvinyl fluoride, polyvinylidene chloride, polyvinylidene
fluoride, polyvinyl acetate, polymethyl vinyl ether and polybutyl
vinyl ether; polymers derived from maleinimide and/or maleic anhydride,
such as copolymers of maleic anhydride with styrene; polyvinyl pyrrolidone;
ABS; ASA; polyamides; polyimides; polyamidimides; polysulfones;
polyether sulfones; polyphenylene oxides; polyurethanes; polyureas;
polycarbonates; polyarylenes; polyarylenesulfides; polyepoxides;
polyolefins, such as polyethylene and polypropylene; polyalkadienes;
biopolymers and their derivatives, such as cellulose, cellulose
ethers and cellulose esters, such as ethylcellulose, nitrocellulose,
cellulose acetate and cellulose butyrate, starch, chitin, chitosan,
gelatine, zein; natural resins; synthetic resins, for example alkyd
resins, acrylic resins, phenolic resins, epoxy resins, aminoformaldehyde
resins, such as urea/formaldehyde and melamine/formaldehyde resins;
rubber; casein; silicone and silicone resins; caoutchouc, chlorinated
rubber; and also polymers which are used, for example, as binders
in paints, such as novolaks derived from C.sub.1 -C.sub.6 aldehydes,
e.g. formaldehyde and acetaldehyde, and from a binuclear or mononuclear,
preferably mononuclear, phenol which, if desired, may be substituted
by one or two C.sub.1 -C.sub.9 alkyl groups, one or two halogen
atoms or a phenyl ring, such as o-, m- or p-cresol, xylene, p-tert-butylphenol,
o-, m- or p-nonylphenol, p-chlorophenol or p-phenylphenol, or from
a compound containing more than one phenolic group, typically resorcinol,
bis(4-hydroxyphenyl)methane or 22-bis(4-hydroxyphenyl)propane;
as well as suitable mixtures of the cited materials.
Particularly preferred high molecular weight organic materials,
especially for the preparation of a paint system, printing ink or
ink, are, for example, cellulose ethers and esters, such as ethylcellulose,
nitrocellulose, cellulose acetate and cellulose butyrate, natural
resins or synthetic resins (polymerisation or condensation resins),
for example aminoplasts, in particular urea/formaldehyde resins
and melamine/formaldehyde resins, alkyd resins, phenolic plastics,
polycarbonates, polyolefins, polystyrene, polyvinyl chloride, polyamides,
polyurethanes, polyesters, ABS, ASA, polyphenylene oxide, rubber,
casein, silicone and silicone resins as well as their possible mixture
with each other.
It is also possible to use high molecular weight organic materials
in dissolved form as film formers, for example boiled linseed oil,
nitrocellulose, alkyd resins, phenolic resins, melamine/formaldehyde
and urea/formaldehyde resins and acrylic resins.
The cited high molecular weight organic compounds can be obtained
singly or in mixtures, for example as granulate, plastics, melts
or in the form of solutions, in particular for the preparation of
spinning solutions, paint systems, coatings, inks or printing inks.
In a particularly preferred embodiment of this invention, the novel
molecular sieves are used for mass coloring polyvinyl chloride,
polyamides and, in particular, polyolefins such as polyethylene
and polypropylene, and for the preparation of paint systems, in
particular automotive lacquers, and of powder coatings, inks, printing
inks and coating compounds.
Preferred binders for paint systems to be mentioned as examples
are alkyd/melamine surface coating resins, acryl/melamine surface
coating resins, cellulose acetate/cellulose butyrate paints and
two-component paints based on polyisocyanate of crosslinkable acrylic
resins.
According to findings so far, the novel molecular sieves can be
added to the material to be colored in any desired amount depending
on the end use requirements. In the case of high molecular weight
organic materials, for example, the novel molecular sieves can be
used in amounts in the range from 0.2 to 40 preferably from 0.5
to 20% by weight, based on the total weight of the pigmented high
molecular weight organic material.
The high molecular weight organic materials are normally colored
with the novel molecular sieves such that said molecular sieves,
if desired in the form of masterbatches, are admixed to the high
molecular weight organic materials using customary suitable appliances,
for example roll mills, mixing or grinding apparatus. The pigmented
material is then usually brought into the desired final form by
methods known per se, such as calendering, moulding, extruding,
coating, casting or injection moulding.
To produce non-brittle mouldings or to reduce their brittleness,
so-called plasticisers may be added to the high molecular weight
substances prior to moulding. These plasticisers may be, for example:
the esters of phosphoric acid, phthalic acid and sebacic acid. The
plasticisers can be added before, during or after coloring the high
molecular substances with the novel molecular sieves.
To obtain different shades, the novel molecular sieves can be advantageously
added in admixture with fillers, transparent or opaque white, colored
or black pigments and conventional luster pigments in the desired
amount.
To prepare paint systems, coating compositions, inks and printing
inks, the corresponding high molecular weight organic substances,
such as binders, synthetic resin dispersions and the like, and the
novel molecular sieves, are usually dispersed or dissolved, if desired
together with customary additives, such as fillers, paint auxiliaries,
siccatives, plasticisers and/or additional pigments, in a shared
solvent or solvent mixture. This may be effected by dispersing or
dissolving the individual components by themselves or also several
together and only then bringing all components together, or by adding
all of them in one go.
For printing applications, all conventional industrial printing
methods may be used, such as screen printing, rotogravure, bronze
printing, flexographic printing and offset printing.
Accordingly, another aspect of this invention also relates to materials
such as high molecular weight organic materials, preferably biopolymers
and plastic materials, ceramic products, for formulations of decorative
cosmetics, paint systems, preferably automotive lacquers, printing
inks, inks, dispersion paints and color filters which contain the
novel molecular sieves.
As compared to colorant-containing molecular sieves of the state
of the art, the novel molecular sieves have enhanced leaching and
bleeding behaviour, improved thermal stability, enhanced resistance
to solvents and enhanced light stability. In addition, the novel
molecular sieves have better chemical resistance. Furthermore, the
colorant load is higher than in comparable known compounds.
EXAMPLES
The following Examples always use molecular sieves which have been
dehydrated by heating.
The molecular sieves are in this case heated to 450.degree. C.
at a heating rate of 1.degree. C./min and are then dehydrated at
this temperature and at a reduced pressure of 100 mPa (10.sup.-3
mbar) for 12 h.
Example 1
(a) 3.03 g of zeolite HY (obtained by ion exchange from zeolite
NaY, of Degussa AG) are heated with 1.01 g of quinizarin at 160.degree.
C. for three days at a reduced pressure of 300 mPa. The cooled reaction
mixture is then extracted with 300 ml of pyridine at reflux in a
Soxhlet apparatus until the extract in the siphon tube of the apparatus
is colorless. Subsequently, the molecular sieve extracted with pyridine
is extracted with 300 ml of acetone at reflux in a Soxhlet apparatus
until the extact in the siphon tube is colorless. The solvent is
then removed from the extracted molecular sieve at a reduced pressure
of 300 mPa and at 100.degree. C. over 12 h.
b) A stream of nitrogen is passed through a vessel filled with
silicon tetrachloride at room temperature and is saturated thereby.
The SiCl.sub.4 -saturated stream of nitrogen is then passed for
3 h over 2 g of the colorant-loaded molecular sieve prepared according
to (a), which is in a tube furnace and which is heated to 150.degree.
C. Excess silicon tetrachloride is then removed by flushing for
1 hour with a pure stream of nitrogen at room temperature.
Example 2
(a) 3.00 g of an ultrastable dealuminised zeolite HY (of PQ Corporation)
are heated with 1.00 g of indigo at 240.degree. C. for three days
at a pressure of 300 mPa. The cooled reaction mixture is then extracted
with 300 ml of pyridine at reflux in a Soxhlet apparatus until the
extract in the siphon tube is colorless. The molecular sieve extracted
with pyridine is then extracted with 300 ml of acetone at reflux
in a Soxhlet apparatus until the extract in the siphon tube is colorless.
Subsequently, the solvent is removed from the extracted molecular
sieve at a reduced pressure of 300 mPa and at 100.degree. C. over
12 h.
b) A stream of nitrogen is passed through a vessel filled with
silicon tetrachloride at room temperature and is saturated thereby.
The SiCl.sub.4 -saturated stream of nitrogen is then passed for
3 h over 2 g of the colorant-loaded molecular sieve prepared according
to (a), which is in a tube furnace and which is heated to 150.degree.
C. Excess silicon tetrachloride is then removed by flushing for
1 hour with a pure stream of nitrogen at room temperature.
Example 3
(a) 3.00 g of zeolite H-mordenite (of CU Chemie Uetikon AG) are
heated with 1.01 g of indigo at 240.degree. C. for three days at
a pressure of 300 mPa. The cooled reaction mixture is then extracted
with 300 ml of pyridine at reflux in a Soxhlet apparatus until the
extract in the siphon tube is colorless. The molecular sieve extracted
with pyridine is then extracted with 300 ml of acetone at reflux
in a Soxhlet apparatus until the extract in the siphon tube is colorless.
Subsequently, the solvent is removed from the extracted molecular
sieve at a reduced pressure of 300 mPa and at 100.degree. C. over
12 h.
b) A stream of nitrogen is passed through a vessel filled with
silicon tetrachloride at room temperature and is saturated thereby.
The SiCl.sub.4 -saturated stream of nitrogen is then passed for
3 h over 2 g of the colorant-loaded molecular sieve prepared according
to (a), which is in a tube furnace and which is heated to 150.degree.
C. Excess silicon tetrachloride is then removed by flushing for
1 hour with a pure stream of nitrogen at room temperature.
Example 4
Example 3 is repeated, but using as colorant 0.84 g of N,N'-dimethyl-14-dike-to-36-diphenylpyrrolo-[34-c]pyrrole
(prepared according to Example 1 of U.S. Pat. No. 4585878; hereinafter
called DPP1) and 3.01 g of zeolite NaY (of Degussa AG). The solvent
is then removed over 12 h and the zeolite is loaded with DPP1 at
150.degree. C.
Example 5
The procedure of Example 4 is repeated, but replacing zeolite NaY
with 7.01 g of zeolite H-mordenite (of CU Chemie Uetikon AG) and
2.33 g of DPP1. |