U.S. patent application number 12/285271 was filed with the patent office on 2009-02-12 for supramolecular composite film material and method for fabricating.
This patent application is currently assigned to NITTO DENKO CORPORATION. Invention is credited to Alexander S. Grodsky, Alexander F. Krivoschepov, Pavel I. Lazarev.
Application Number | 20090039321 12/285271 |
Document ID | / |
Family ID | 46205594 |
Filed Date | 2009-02-12 |
United States Patent
Application |
20090039321 |
Kind Code |
A1 |
Grodsky; Alexander S. ; et
al. |
February 12, 2009 |
Supramolecular composite film material and method for
fabricating
Abstract
The present invention provides an optically anisotropic
composite film material possessing improved working
characteristics, including hydrolytic stability and mechanical
strength with respect to environmental factors. These and other
advantages of the present invention may be achieved by creating a
supramolecular composite film material. This supramolecular
composite film material comprises a matrix of thin crystal film
composed of organic supramolecules containing polar groups, and a
binding agent representing a water-soluble aliphatic compound
containing at least two functional groups. The present invention
further provides a method for manufacturing supramolecular
composite film materials possessing these advantageous properties.
In one embodiment, the method comprises the following steps: (i)
formation of a layer of lyotropic liquid crystal composed of
supramolecules of a cyclic organic compound with conjugated
.pi.-systems and substituted polar groups; (ii) application of an
external orienting force to said layer and further removal of a
solvent with the resulting formation of a thin crystal film; (iii)
treatment of the thin crystal film with a solution of inorganic
salts leading to the formation of an insoluble crystalline film of
supramolecules composed of said organic molecules; (iv)
impregnation of said insoluble film with a binding agent capable of
interacting with the polar groups with the subsequent formation of
a filled film; and (v) drying of said filled film leading to the
formation of a supramolecular composite film material.
Inventors: |
Grodsky; Alexander S.;
(Moscow, RU) ; Krivoschepov; Alexander F.;
(Malakhovka, RU) ; Lazarev; Pavel I.; (London,
GB) |
Correspondence
Address: |
WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP
1250 CONNECTICUT AVENUE, NW, SUITE 700
WASHINGTON
DC
20036
US
|
Assignee: |
NITTO DENKO CORPORATION
Osaka
JP
|
Family ID: |
46205594 |
Appl. No.: |
12/285271 |
Filed: |
October 1, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11132746 |
May 18, 2005 |
|
|
|
12285271 |
|
|
|
|
60578338 |
Jun 8, 2004 |
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Current U.S.
Class: |
252/582 ;
106/287.25; 106/287.26; 106/287.35 |
Current CPC
Class: |
C09K 19/02 20130101;
Y10T 428/31504 20150401; C09K 2219/03 20130101 |
Class at
Publication: |
252/582 ;
106/287.35; 106/287.25; 106/287.26 |
International
Class: |
F21V 9/00 20060101
F21V009/00; C09D 7/00 20060101 C09D007/00 |
Claims
1. A supramolecular composite film material comprising a matrix of
supramolecules containing polar groups and crystallized in thin
crystal film, and an aliphatic binding agent containing at least
two functional groups.
2. The supramolecular composite film material according to claim 1,
wherein each of said suprarnolecules is a chain of cyclic organic
molecules with conjugated .pi.-systems, and linked by .pi.-.pi.
bonds, having the general formula {M}n(F)d, where M is an organic
molecule; n is the number of molecules in the chain, having
magnitude up to 10000, F is La polar group exposed to
intersupramolecular space; and d is the number of polar groups per
molecule, varying from 1 to 4.
3. The supramolecular composite film material according to claim 1,
wherein said polar group is ionogenic.
4. The supramolecular composite film material according to claim 3,
wherein said polar ionogenic group is associated with one or more
counterions.
5. The supramolecular composite film material according to claim 4,
wherein said counterions represent alkaline earth metal ions.
6. The supramolecular composite film material according to claim 1,
in wherein the matrix of supramolecules accounts for up to about 95
mass % of the composite film material.
7. The supramolecular composite film materials according to claim
1, wherein said binding agent is water-soluble.
8. The supramolecular composite film materials according to claim
1, wherein said functional groups of the binding agent molecules
interact with formation of hydrogen bonds and/or chemical
bonds.
9. The supramolecular composite film materials according to claim
2, wherein said functional groups of the binding agent molecules
interact with the cyclic organic molecules of supramolecules with
the formation of hydrogen bonds and/or ionic bonds.
10. The supramolecular composite film materials according to claims
9, wherein the interaction of the binding agent with said cyclic
organic molecules does not disturb the matrix of
supramolecules.
11. The supramolecular composite film materials according to claim
9, wherein said functional groups of the binding agent molecules
interact with the polar groups of the cyclic organic molecules that
belong to the different supramolecules or different fragments of
the supramolecule.
12. The supramolecular composite film materials according to claim
1, wherein said binding agent contains amino and/or hydroxy
groups.
13. The supramolecular composite film material according to claim
12, wherein said binding agent is selected from the class of
methylol carbamides and their derivatives.
14. The supramolecular composite film material according to claim
1, wherein said binding agent further comprises additives of
diatomic or polyatomic alcohols.
15. The supramolecular composite film material according to claim
14, wherein the amount of said alcohol additives to the binding
agent falls within the ratio interval of (0.1-1.0) to 2.
16. The supramolecular composite film material according to claim
1, wherein said material is anisotropic and possesses a crystalline
structure with an interplanar spacing of 3.4.+-.0.3 .ANG. along one
of the optical axes.
17. The supramolecular composite film material according to claim
1, wherein said material is polarizing.
18. The supramolecular composite film material according to claim
1, wherein said material is a retarder or light filter.
19.-34. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of the U.S.
application Ser. No. 11/132,746 dated May 18, 2005 which claims
benefit under 35 U.S.C. .sctn. 119(e) to application Ser. No.
60/578,338, filed Jun. 8, 2004, the disclosures of which are hereby
incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of
crystalline composite film materials. In particular the present
invention relates generally to microelectronics, optics,
communications, computer technology, and other related fields.
BACKGROUND OF THE INVENTION
[0003] The development of modern technology requires creating new
materials, in particular composites, that constitute a basis for
fabricating optical, electronic, and other elements with desired
properties.
[0004] Composites or composite materials represent systems composed
of two or more different components or in other word phases. One of
the components is continuous and is called the matrix or base,
while the other components are distributed in the matrix in the
form of inclusions, in particular particles, fibers, layers, and
are referred to as fillers or dispersed phases. A composite
material or a composite is a heterogeneous disperse system, the
properties of which are not simple combinations of the properties
of components. The properties of a composite material can be
controlled by modifying the interaction between the matrix and
fillers, by selecting proper fillers, and by varying the ratio of
components. An important role in obtaining composite materials with
desired properties is played by physicochemical parameters of the
filler particles.
[0005] A composition for obtaining optically transparent materials
was disclosed in U.S. Pat. No. 4,143,017 and comprises copolymers
containing unsaturated glycols, water, and an organic fillers
imparting improved mechanical properties to the final composite,
while retaining high optical properties of the components. The
fillers represent polyfunctional monomers containing at least one
carboxy group, which serve as cross-linking agents.
[0006] Various types of the filler molecules containing
polymerizable groups were described in the European Patent EP
0,389,420.
[0007] Fillers may represent various combinations of substances,
which can be organic and/or inorganic. For example, a
liquid-crystalline polymer system and an aqueous polymeric
dispersion containing both organic and inorganic fillers, were
described in PCT patent publications WO 0040655 and WO 0040629. The
inorganic components used were alkaline earth metal salts.
[0008] Another example of a polymeric composition used in the
liquid crystal display backlight system is disclosed in the
European Patent EP 0,847,424 and comprises a polymer film covered
with a polymeric binder containing both organic and inorganic
fillers. The binder is transparent and retains its optical
properties for a long time.
[0009] The optical properties of a two-component liquid-crystalline
system were studied for anisotropic films based on poly(vinyl
alcohol) (PVA) modified with iodine [see Bahadur, B., Liquid
Crystals Applications and Uses, ed., Vol. 1, World Scientific,
Singapore, N.Y., July 1990, p. 101].
[0010] However many optical materials based on polymers, in
particular PVA-based films with dye additives, have relatively low
thermal stability which put a limit on their application.
[0011] A special class of polymers is represented by supramolecular
polymers, see for example Brandveld, L., Supramolecular Polymers,
Chem. Rev., 101, 4071-97 (2001). The structural units are linked by
noncovalent bonds such as hydrogen bonds, complex bonds, and
arene-arene bonds. The monomers represent self-assembly discotic
molecules, typically of organic dyes, containing various
substituted ionic groups. In aqueous solutions, such discotic
molecules exhibit aggregation with the formation of a lyotropic
liquid crystal.
[0012] The important role of intermolecular links of the hydrogen
bond type in the formation of supramolecular polymer compositions
was described for example in European Patent EP 1,300,447. Such
bonds appear as a result of the interaction between functional
groups of adjacent polymer chains.
[0013] The U.S. Pat. No. 5,730,900 discloses method of obtaining a
film comprising polymer matrix. By the disclosed method an initial
solution comprises a discotic substituted polycyclic compound
containing polymerizable groups in the substituents, and a
liquid-crystalline substance. The substrate is an oriented polymer
substrate. After the disclosed treatment and further cooling a film
is formed comprising polymer matrix with liquid-crystalline
inclusions representing the bound filler. This conversion of a
two-component mixture leads to the formation of a matrix-polymer
system with protection layers, retaining the liquid-crystalline
properties in the final film. However, use of organic solvents, the
required individual selection of the solvents for the system
components, the required high temperatures and/or UV radiation make
the aforementioned polymerization process technologically
complicated and not environmentally appropriate.
[0014] Another class of compounds for the obtaining of modified
optical film materials possessing new properties is offered by
modified water-soluble dichroic organic dyes with planar molecular
structures. Heterocyclic molecules and molecular aggregates of such
compounds are characterized by a strong dichroism in the visible
spectral range. The process of manufacturing thin crystal films
based on such materials does not have the disadvantages of the
technology of the art. The manufacturing process includes the
following stages. In the first stage, a water-soluble dye forms a
lyotropic liquid crystal phase. This phase comprises columnar
aggregates composed of discotic molecules of the dichroic dyes [see
for example Yeh, P., et al., Molecular Crystalline Thin Film
E-Polarizer, Mol. Mater., 14 (2000)]. These molecules are capable
of aggregating even in dilute solutions [see Lydon, J., Chromonics,
In: Handbook of Liquid Crystals, 1998, pp. 981-1007]. In the second
stage, application of the lyotropic liquid crystal phase (in the
form of ink or paste) with shear aligns molecular columns in the
direction of shear. High thixotropy of the applied liquid crystal
provides high molecular ordering in the shear-induced state and its
preservation after termination of the shear action. In the third
stage of the process, evaporation of the solvent (water) leads to
unidirectional crystallization with the formation of an organic
solid crystal film from the pre-oriented liquid crystal phase as
generally described in the U.S. Pat. No. 6,563,640. Such Thin
Crystal Films (TCFs) are characterized by high optical anisotropy
of refraction and absorption indices, exhibit the properties of
extraordinary polarizers as described in more details in Bobrov,
Yu. A., J. Opt. Tehnol., 66, 547 (1999), and are available for
commercial application in liquid crystal displays as was generally
described in Ignatov, L. et al., Society for Information Display,
Int. Symp. Digest of Technical Papers, Long Beach, Calif., May
16-18, Vol. XXXI, 834-838 (2000).
[0015] The optical anisotropic film manufactured by this technology
is limited in the high-humidity environment. As disclosed in U.S.
Pat. No. 6,563,640 the films may be additionally treated with the
solution containing ion of bi- or tri-valence metals. As the final
product of this treatment the non-soluble film is formed. However,
the water content can fluctuate with the elevated temperature and
high humidity which results in decrease of stability of the optical
characteristics.
SUMMARY OF THE INVENTION
[0016] The present invention provides an optically anisotropic
composite film material possessing improved working
characteristics, including hydrolytic stability and mechanical
strength with respect to environmental factors. These and other
advantages of the present invention may be achieved by creating a
supramolecular composite film material. This supramolecular
composite film material comprises a matrix of thin crystal film
composed of organic supramolecules containing polar groups, and a
binding agent representing a water-soluble aliphatic compound
containing at least two functional groups.
[0017] The present invention further provides a method for
manufacturing supramolecular composite film materials possessing
these advantageous properties. In one embodiment, the method
comprises the following steps: (i) formation of a layer of
lyotropic liquid crystal composed of supramolecules of a cyclic
organic compound with conjugated .pi.-systems and substituted polar
groups; (ii) application of an external orienting force to said
layer and further removal of a solvent with the resulting formation
of a thin crystal film; (iii) treatment of the thin crystal film
with a solution of inorganic salts leading to the formation of an
insoluble crystalline film of supramolecules composed of said
organic molecules; (iv) impregnation of said insoluble film with a
binding agent capable of interacting with the polar groups with the
subsequent formation of a filled film; and (v) drying of said
filled film leading to the formation of a supramolecular composite
film material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Other objects and advantages of the present invention will
become apparent upon reading the detailed description of the
invention and the appended claims provided below, and upon
reference to the drawings, in which:
[0019] FIG. 1 shows the dependence of the thickness of a
supramolecular composite film on the relative humidity for a thin
crystal film (TCF) treatment with an inorganic salt and with an
impregnating solution of methylol carbamides and glycerol (MCGl).
TCF with (curve 2) and without (curve 1) treated of
MC(2%)+Gl(1%).
[0020] FIG. 2 shows the contrast ratio versus transmission (CR-T
curve) for an insoluble TCF of sulfonated derivatives of
indanthrone, naphthalenetetracarboxylic acid and
perylenetetracarboxylic acid (INP) with and without treatment with
an impregnating solution of methylol carbamides (MC) before and
after the baking test at 230.degree. C. Non-treated TCF before (1)
and after (2) the baking test, TCF treated with 10%-MC solution
before (3) and after (4) the baking test.
[0021] FIG. 3 shows CR-T curves for an insoluble TCF of INP with
and without treatment with an impregnating solution of MCGl before
and after the baking test at 230.degree. C. Non-treated TCF before
(1) and after (2) the baking test, TCF treated with MC(4%)+Gl(2%)
solution before (3) and after (4) the baking test.
[0022] FIG. 4 shows CR-T curves for an insoluble TCF of INP with
and without treatment with an impregnating solution MCGl before and
after the environmental test. Non-treated TCF before (1) and after
(2) the environmental test, TCF treated with MC(2.5%)+Gl(1.2%)
solution before (3) and after (4) the environmental test.
[0023] FIG. 5 shows CR-T curves for an insoluble TCF based on an
aqueous solution of a mixture of sulfonated products of indanthrone
with and without treatment with an impregnating solution before and
after the baking test at 230.degree. C. Non-treated TCF before (1)
and after (2) the baking test, TCF treated with MC(2.5%)+Gl(1.2%)
solution before (3) and after (4) the baking test.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present invention provides optically anisotropic films
of a composite material possessing selective optical properties in
a broad wavelength range and a method of obtaining such films. The
material can be based on various organic substances capable of
forming lyotropic liquid crystal phases in solution. Application of
this material onto a substrate, followed by the external orienting
force on the lyotropic liquid crystal phases and removal of the
solvent, leads to the formation of thin, anisotropic crystalline
films comprising ordered systems of organic molecules.
[0025] The increased mechanical strength and improved physical
properties ensuring proper functioning of the optical films, in
particular their stability under the conditions of high
temperatures and humidity, are provided by treatment of the films
with inorganic salts and water-soluble organic compounds capable of
interacting with liquid crystal molecules.
[0026] The disclosed optically anisotropic films of a composite
material possess higher stability with respect to environmental
factors, improved mechanical properties, and better optical
characteristics as compared to untreated films. Yet another
embodiment of the present invention provides a method for obtaining
said films.
[0027] The present invention employs supramolecules composed of
organic molecules possessing a planar configuration, containing
substituted polar groups, and linked by noncovalent .pi.-.pi.
bonds. With respect to their chemical structure, these molecules
belong to cyclic compounds (including aromatic and heterocyclic
ones) with conjugated systems of .pi. bonds. These molecules
contain substituted modifying groups, which can be either polar or
nonpolar. The polar groups are hydrophilic and provide for the
solubility of said molecules of organic compounds in water and
other polar solvents. The nonpolar groups are hydrophobic and
determine the solubility in nonpolar solvents and the required
spectral characteristics. One class of such compounds is offered by
organic dyes.
[0028] Said supramolecules comprise the chains of cyclic organic
molecules with conjugated .pi.-systems linked by .pi.-.pi.
(arene-arene) bonds, having the general formula
{M}n(F)d,
[0029] where M is an organic molecule; n is the number of molecules
in the chain (up to 10000), F is a polar group exposed to
intersupramolecular space; and d is the number of polar groups per
molecule (varying from 1 to 4).
[0030] The polar groups can be ionogenic and nonionogenic.
Ionogenic polar groups typically represent the anionic groups of
strong mineral acids, including sulfonic, sulfate, and phosphate
groups, as well as less polar carboxy groups. In addition, these
groups may represent cationic fragments such as amino and some
amphoteric groups possessing pH-dependent properties. In solution,
the polar groups are always accompanied by one or several (like or
unlike) counterions. Polyvalent counterions may simultaneously
belong to various molecules. Nonionogenic polar groups include
hydroxyl, chlorine, bromine, and the like.
[0031] The nonpolar groups belong predominantly to numerous classes
of organic fragments, such as methyl, ethyl, ethoxy, etc.
[0032] The molecules of organic compounds under consideration
possess planar configuration, usually of an ellipsoidal shape.
These molecules can be either symmetric or asymmetric, with
substituents arranged at the periphery. The molecules are
amphiphilic and may simultaneously contain substituted groups of
either like or unlike chemical nature.
[0033] As is known, a driving force for the formation of molecular
aggregates or supramolecules is the .pi.-.pi. interaction between
planar molecules (e.g., of dyes). The salvation, that is,
preferential interaction of the modifying polar groups with the
solvent, leads to the formation of an ordered structure of
supramolecules of the same type, called lyotropic liquid crystal
(LLC) system or mesophase. An LLC system is characterized by a
phase diagram with a domain of stability over a broad range of
concentrations, temperatures, and pH values.
[0034] The formation of such LLC mesophases by the organic
substances under consideration in a polar solvent is a condition
necessary to achieve the objectives of the disclosed invention. The
polar solvent can be water or a mixture of water and an organic
solvent miscible with water in any proportion.
[0035] The disclosed invention makes use of water-soluble organic
substances capable of forming mesophases, which were described in
detail in the United States Published Patent application No.
US2001/0029638 which is incorporated herein by reference in its
entirety, and include but not limited to the following classes of
compounds:
[0036] polymethine dyes (e.g., pseudoisocyanine, piacyanol);
[0037] triarylmethane dyes (e.g., Basic Turquose, Acid Light Blue
3);
[0038] diaminoxanthene dyes (e.g., sulforhodamine);
[0039] acridine dyes (e.g., Basic Yellow K);
[0040] sulfonated acridine dyes (e.g., trans-quinacridone);
[0041] water-soluble derivatives of anthraquinone dyes (e.g.,
Active Light Blue KX);
[0042] sulfonated vat dye products (e.g., flavanthrone, Indanthrene
Yellow, Vat Yellow 4K, Vat Dark Green G, Vat Violet C, indanthrone,
Perylene Violet, Vat Scarlet 2G);
[0043] azo dyes (e.g., Benzopurpurin 4B, Direct Lightfast Yellow
O);
[0044] water-soluble diazine dyes (e.g., Acid Dark Blue 3);
[0045] sulfonated dioxazine dye products (pigment Violet
Dioxazine);
[0046] soluble thiazine dyes (e.g., Methylene Blue);
[0047] water-soluble phthalocyanine derivatives (e.g., copper
octacarboxyphthalocyanine salts);
[0048] fluorescent whiteners;
[0049] disodium chromoglycanate;
and some other, including Perylenetetracaboxylic Acid Diimide Red
(PADR), benzimidazoles of PADR (violet) and
naphthalenetetracarboxylic acid (yellow, claret), sulfoderivatives
of benzimidazoles and phenanthro-9, 10:2,3-quinoxaline, etc.
[0050] Lyotropic liquid crystal mesophase is formed by using
ionogenic organic molecules in the form of water-soluble
sulfoderivatives, either individually or in mixtures of such
compounds.
[0051] Cationic counterions in the disclosed systems can be but not
limited to H+, NH+4, K+, Li+, Na+, Cs+, Ca.sup.2+, Sr.sup.2+,
Mg.sup.2+, Ba.sup.2+, Co.sup.2+, Mn.sup.2+, Zn.sup.2+, Cu.sup.2+,
Pb.sup.2+, Fe.sup.2+, Ni.sup.2+, Al.sup.3+, Ce.sup.3+, La.sup.3+,
etc., as well as mixtures of these and other cations.
[0052] When dissolved in water, the molecules of these
sulfoderivatives or their mixtures form anisometric (rod-like)
aggregates packed as stacked coins. Each aggregate in such a
solution represents a micelle with an electric double layer, while
the entire solution represents a highly dispersed (colloidal)
lyophilic system. As the solution concentration (i.e., micelle
concentration) is increased, the anisometric aggregates exhibit
spontaneous ordering which is also named self-ordering. This leads
to the formation of a nematic lyotropic mesophase, whereby the
system becomes liquid-crystalline. The high order of dye molecules
in the columns allows their mesophases to be used for obtaining
oriented dichroic materials. The films formed from these materials
possess a high degree of optical anisotropy. The liquid crystal
state is readily verified by usual methods, for example, with the
aid of a polarization microscope.
[0053] The content of said sulfoderivatives or their mixtures in
the LLC mesophase ranges from 3 to 50 mass %, most typically being
within 7 to 30 mass %. Said LLC system may additionally contain up
to 5 mass % of surfactants and/or plasticizers.
[0054] By varying the number of sulfonic groups, typically from one
to four, and the number and character of other substituents (such
as ethyl, methyl, chlorine, bromine) in the dye molecules, it is
possible to control the hydrophilic-hydrophobic balance of
aggregates formed in liquid-crystalline solutions and to change the
solution viscosity. This, in turn, affects the dimensions and
shapes of supramolecules and influences the degree of molecular
ordering of these supramolecules, which provides for a required
solubility and a high stability of the related LLC systems. The
distance between supramolecules is typically within 40-100
.ANG..
[0055] All the aforementioned compounds are capable, both
separately and in mixtures with one another or with the other
dichroic dyes, as well as with some organic compounds which are
colorless or weakly absorbing in the visible spectral range, of
forming stable LLC mesophases in solution. After removal of the
solvent, these mesophases can form anisotropic, at least partially
crystalline films possessing high optical characteristics.
[0056] The LLC solution is concentrated by evaporating the solvent,
for example, on heating to a relatively low temperature, by
distillation in vacuum, or by diafiltration. This treatment may
lead to the formation of a paste-like substance or the so-called
"ink", capable of retaining the liquid crystal state for a
sufficiently long time.
[0057] A layer of the LLC system is formed by applying the solution
or concentrate onto a clean substrate surface. The substrates are
usually made of a glass or a polymer, including but not limited to
poly(ethylene terephthalate) (PET), polycarbonate, polyarylates,
etc., and can possess any desired shape.
[0058] Then, the LLC layer is subjected to orientation. There are
known methods of the external orienting force, which are based on
the use of various factors: mechanical, electrical, magnetic, etc.
The intensity of this force, which must be sufficient to provide
for a required orientation to the kinetic units (supramolecules) of
the LLC mesophase, depends on the properties of the
liquid-crystalline solution, such as its nature, concentration,
temperature, etc. The resulting oriented structure is a basic
property of the disclosed material and related articles made of
this material. Further description is found in U.S. Pat. Nos.
5,739,296; 6,174,394; and 6,563,640 which are incorporated herein
by reference in their entirety.
[0059] According to the disclosed invention, the external orienting
force upon the layer of a lyotropic liquid crystal system of
organic molecules is produced by mechanical shear. This is achieved
through directed mechanical motion of one or several alignment
devices of various types, including a knife, a cylindrical wiper,
or a flat plate, oriented parallel to the applied layer surface or
at an angle to this surface, a slot die or any other alignment
devices. A distance from the surface to the edge of the alignment
tool is set so as to obtain a film of required thickness.
[0060] The subsequent process of solvent removal is performed under
mild conditions at room temperature for a time period up to
approximately 1 hour, or by heating in the temperature range from
approximately 20 to 60.degree. C. for the sake of time saving, and
at a relative humidity of 40-70%. This treatment leaves the
substrate covered by an oriented thin layer of the organic
supramolecules, called thin crystal film (TCF).
[0061] The regime of solvent removal is selected so as to exclude
the possibility of impairing orientation of the previously formed
LLC structure, while providing for the relaxation of stresses
arising in the course of the external orienting force. Care should
be taken to avoid over-drying of the LLC layer prior to the TCF
formation on the substrate surface. It is recommended to perform
the solvent removal stage under conditions of elevated humidity.
Critical factors ensuring a high degree of crystallinity of the
material layer are the rate and the directional character of the
process of solvent removal from the system. The resulting layer
represents a sufficiently thin continuous film possessing an
ordered molecular structure, in which organic molecules are
aggregated in orientation-ordered ensembles. The formation of this
structure is determined by a special liquid-crystalline state of
molecules in solution, in which they already possess a local order,
entering into one- and/or two-dimensional mutually oriented
quasicrystalline aggregates. Applied onto a substrate surface, with
simultaneous application of the external orienting force, such a
system acquires macroscopic orientation. This orientation is not
only retained in the course of drying, but may even increase due to
crystallization.
[0062] The subsequent compulsory stage according to the disclosed
process is the treatment of the obtained TCF of supramolecules with
an aqueous solution of mineral salts in order to convert the film
into an insoluble form. For this purpose, it is possible to use,
for example, a solution of barium chloride (BaCl.sub.2) with a
concentration in the range from 5 to 30%, the optimum interval
being 10-20%. During the treatment, Ba.sup.2+ ions are replaced
with NH.sub.4.sup.+ ions (counterions to the polar groups of
supramolecules) with the formation of insoluble organic barium
sulfates. Unreacted barium sulfate, which can partially penetrate
into pores and structural defects of the film, is subsequently
removed by washing in water. Then, the film is dried in air at room
temperature or at an elevated temperature in the range from 20 to
70.degree. C. for up to approximately 20 min depending on the
temperature.
[0063] The next stage in the disclosed technological cycle consists
in the impregnation of insoluble TCFs with a solution of a
water-soluble organic binding agent capable of, first, rapidly
interacting with sulfonic and other polar groups of organic
molecules exposed to the intersupramolecular space, and second,
forming crosslinks.
[0064] The binding agent is selected from the class of aliphatic
compounds including methylol carbamides (MCs), for example,
monomethylol carbamide (H.sub.2N(CO)NHCH.sub.2OH) and dimethylol
carbamide (HOH.sub.2CHN(CO)NHCH.sub.2OH) obtained by interaction of
carbamide (NH.sub.2CONH.sub.2) with formaldehyde (HCHO). The MC
molecules are capable of polymerizing with one another via
interaction of their functional amino and hydroxy groups. This
results in the formation of macromolecules of various lengths, from
dimmers and trimers to oligomers and high-molecular-mass compounds
with the degree of polymerization around or above 100 with a chain
length exceeding the distance between stacks in macromolecules.
[0065] When a monomer solution is applied onto the TCF surface, MC
molecules diffuse into the film and spread between the stacks.
Depending on a particular site and concentration in the film,
molecules of the binding agent exhibit various transformations.
These molecules form chemical bonds of ether ionic or hydrogen type
with each other or with polar groups of organic dye molecules.
[0066] The MC polycondensation proceeds at pH<5 and is catalyzed
by various acids. The process can be accelerated through heating.
The reaction is described by the following scheme:
--NHCH.sub.2OH+HOCH.sub.2NH.fwdarw.--NHCH.sub.2OCH.sub.2NH--+H.sub.2O
--NHCH.sub.2OH+HOCH.sub.2NH.fwdarw.--NHCH.sub.2NH--+H.sub.2O+CH.sub.2O
[0067] Depending on their length and conformation, the polymerized
MC molecules bind separate structural fragments of TCF (formed by
crystallized organic supramolecules) belonging either to the same
supramolecule or to different supramolecules. The MC molecules can
polymerize with crosslinking both in the volume of TCF and on the
surface, creating a thin solid composite film. The final film
thickness depends on the initial TCF layer thickness and on the MC
solution concentration. The TCF obtained as a result of
impregnation possesses sufficiently high strength and elasticity.
The network of crosslinks binds the stacks of dye molecules, thus
reinforcing the TCF structure.
[0068] If the impregnating solution contains only MC molecules, a
polymer film formed on the TCF surface is rigid, brittle, and can
lose transparency with time. In order to obtain stable and elastic
films, it is recommended to introduce alcohols with two or more OH
groups into the impregnating solution. The most appropriate
additive is glycerol (Gl) or other di- and polyatomic alcohols,
which is capable of copolymerizing with MC and forming crosslinks
between amino groups and, in addition, produces a plasticizing
action. Moreover, the introduction of glycerol into the
impregnating MC solution significantly (by 15-20%) improves the
optical characteristics of TCFs. The impregnation with MC+Gl
solutions and the formation of thin surface polymer films
significantly increases the environmental stability of TCFs. The
optimum ratio of MC and Gl in the impregnating solution is
2:(0.1-1.0) (w/w). This process is performed, for example, by
dipping a sample into a low-concentration aqueous solution of MC or
a mixture of MC with an alcohol (two- or three-atomic) for a time
from one to several tens of seconds. Finally, the modified film is
dried at room temperature or at an elevated temperature in the
range from 20 to 700 C. during a time period of 1-20 min (or by
alternating these regimes). The drying is accompanied by
elimination of the excess binding agent from the TCF surface and
from supramolecular organic structures.
[0069] The observed increase in the optical characteristics and
thermal stability of TCFs treated with MC+Gl solutions is explained
primarily by binding of the dye fragments into a unified system by
MC and Gl molecules. This can be related both with (i) the
formation of hydrogen bonds between the hydroxy groups of MC and Gl
and the carbonyl and sulfo-groups of the dye and (ii) the
interactions between the amino groups of MC and the sulfo-groups of
the dye. In addition, MC molecules may exhibit polymerization at
pH<5-6 with the formation of a spatial network of their own. The
molecules of Gl may enter into the reaction of polycondensation
with MC. As a result, there appears a TCF based composite material
with MC and Gl playing the role of binding agents. This composite
exhibits increased strength, which is confirmed by the constancy of
the thickness of (MC+Gl)-treated TCFs under the conditions of
increased humidity. As can be seen from the data presented in FIG.
1, the thickness of control (untreated) TCF samples depends on the
relative humidity (RH) of air, exhibiting especially pronounced
variations in the region of RH.gtoreq.60-70%. On the whole, the
thickness of untreated TCFs in the RH interval studied increases by
.about.32%. After the impregnation with a 2% MC-1% Gl solution, the
thickness of samples increases approximately by 13%, but it becomes
much less dependent on the relative humidity. In one test, the
thickness of an impregnated TCF, which was 520 nm at RH=37%,
increased only by 30 nm (5.7%) at RH=72%.
[0070] The above sequence of stages provides a solid composite film
characterized by high strength and thermal stability. In this
composite, the products of chemical conversion of the organic
compounds play the role of fillers, while the TCF film of
supramolecular organic compounds impregnated with inorganic salts
serves as the matrix. The TCF film containing polar groups accounts
for up to 95 mass % of the total material weight. The material is
highly stable with respect to environmental factors such as high
temperatures, withstanding a short-time (within 30 min) heating up
to 230.degree. C. The optical characteristics of the films are
retained during long-term operation under conditions of increased
humidity (RH=95%) and elevated temperatures (up to 80.degree.
C.).
[0071] In all cases described above, the resulting films are
crystalline, with an interplanar spacing on the order of 3.4 .ANG..
The films are birefringent and exhibit dichroic, polarizing, and
phase-shifting (retarding) properties related to the difference in
refractive indices in the mutually perpendicular directions
relative to the optical axis. The film can also possess the
properties of an optical filter. Moreover, the films may combine
the aforementioned properties, together with improved mechanical
characteristics, and can perform the corresponding working
functions.
EXPERIMENTAL
[0072] Experiments were conducted according the method and system
of the present invention. These examples are intended for
illustration purposes only, and are not intended to limit the scope
of the present invention in any way.
Example 1
[0073] A supramolecular composite film material was prepared as
follows. An aqueous solution of the mixture of organic compound
including sulfonated derivatives of indanthrone,
naphthalenetetracarboxylic acid and perylenetetracarboxylic acid
(INP) with a total concentration of 5% was evaporated using a rotor
evaporator to a dye concentration (10-16%) ensuring the formation
of a lyotropic liquid crystal phase. Then, surfactant Triton X-100
was added into the solution in order to improve wetting of the
substrate surface. The resulting working concentration of the
"black" ink was 13%.
[0074] The ink was applied onto the surface of a glass substrate
with simultaneous orientation using a Mayer rod as the aligning
instrument. The film application was performed at 20.degree. C. and
RH=65-70%. After drying under the same conditions, the TCF was
converted into the water-insoluble form (Ba-form) by dipping for
1-2 s into a 10% aqueous solution of barium chloride (BaCl.sub.2).
Then, the sample was lifted up in a vertical position, washed with
deionized (DI) water and dried with air knife.
[0075] The composite film material exhibited anisotropic optical
properties. The polarizing parameters and color coordinates of TCF
(control samples) are presented in FIG. 1 and Table 1. The
measurements were performed in air at room temperature and a
relative humidity RH=45%.
TABLE-US-00001 TABLE 1 Polarizing parameters and color coordinates
of TCFs based on <<black>` ink measured (control samples)
before baking. Color coordinates Two Two Transmittance, % .DELTA.
Single parallel crossed # T H0 H90 Ep CR (CR) Kd A B a B A b 1 42.9
32.8 4.0 88.3 8.1 0.1 14.1 1.21 -4.58 -2.10 1.31 14.06 -31.25 2
40.8 31.0 2.4 92.6 13.0 0.2 14.6 0.81 -3.95 -2.37 1.25 15.28 -33.02
3 39.1 29.4 1.1 96.3 26.6 0.4 16.0 -0.56 -1.53 -3.89 3.40 15.73
-32.57 4 35.8 25.3 0.3 98.9 90.3 4.6 16.3 -2.08 1.01 -4.87 4.54
14.13 -27.84
[0076] Here and below, T is the transmittance of a single sample in
nonpolarized light; H0 and H90 are the transmittances of two
parallel and two crossed polarizers, respectively, in nonpolarized
light; EP is the polarizing efficiency; CR is the contrast ratio;
and Kd is the dichroic ratio.
[0077] In order to increase the thermal stability and improve the
optical properties of TCFs, the samplers were impregnated by
dipping for 30 s into a 10% MC solution at 20.degree. C., followed
by rinsing in DI water and drying with air knife. The optical
characteristics of TCFs after impregnation and drying are presented
in Table 2.
TABLE-US-00002 TABLE 2 Polarizing parameters and color coordinates
of TCF, based on <<black>> ink measured before baking
(Samples were dipped in 10% MC solution, washed in DI water, and
dried with compressed air) Color coordinates Two Two Transmittance,
% .DELTA. Single parallel crossed # T H0 H90 Ep CR (CR) Kd a b a b
a b 5 42.8 32.9 3.8 89.0 8.6 0.1 14.4 1.20 -4.31 -2.12 1.43 14.38
-30.69 6 41.4 31.8 2.5 92.5 12.8 0.2 15.3 0.30 -3.02 -3.30 2.56
14.87 -30.83 7 39.3 29.8 1.1 96.3 26.6 0.4 16.4 -0.40 -1.31 -3.58
3.60 15.58 -31.57 8 36.8 26.8 0.4 98.6 71.2 2.8 16.9 -1.85 1.08
-4.62 4.78 13.20 -25.62
[0078] Then, the control and MC-impregnated TCF samples were
subjected to heating at 230.degree. C. for 20 min (baking test).
The optical characteristics of TCFs after baking are presented in
Table 3.
TABLE-US-00003 TABLE 3 Polarizing parameters and color coordinates
of TCFs based on <<black>> ink measured after baking
Color coordinates Two Two Transmittance, % .DELTA. Single parallel
crossed # T H0 H90 Ep CR (CR) Kd a b a B A b Control 1 42.0 30.3
5.1 84.4 5.9 0.1 10.7 0.71 -3.75 -2.04 1.16 9.26 -22.05 2 39.5 28.2
3.0 89.8 9.3 0.1 11.1 0.57 -3.24 -1.99 1.20 10.15 -23.22 3 37.0
25.9 1.5 94.2 16.9 0.2 11.7 -0.48 -1.51 -3.17 2.67 10.21 -22.46 4
33.0 21.3 0.4 98.1 53.5 1.6 12.0 -1.76 0.84 -3.94 3.83 8.83 -18.54
Samples dipped in 10% MC solution 5 43.2 32.7 4.5 87.0 7.2 0.1 13.5
0.71 -3.54 -2.43 1.89 11.27 -25.18 6 40.8 30.5 2.7 91.5 11.2 0.1
13.6 0.44 -3.22 -2.72 2.04 12.88 -28.35 7 38.2 27.7 1.4 95.0 19.4
0.3 13.4 -0.60 -1.74 -3.72 2.86 12.53 -26.99 8 35.2 24.4 0.4 98.4
62.3 2.2 14.4 -1.73 0.75 -4.28 4.21 11.89 -24.00
[0079] The plots of contrast versus transmission for the untreated
(control) TCFs and the MC-impregnated samples before and after
baking are presented in FIG. 2.
Example 2
[0080] The samples of TCFs on glass substrates were prepared from
11.5% ink using a Mayer rod as the aligning instrument. The ink was
applied at 20.degree. C. and RH=65-70%. After drying under the same
conditions, the TCF was converted into the water-insoluble form
(Ba-form) by dipping for 1-2 s into a 10% aqueous solution of
barium chloride (BaCl.sub.2). Then, the sample was lifted up in a
vertical position, washed with DI water and dried with air
knife.
[0081] The optical characteristics of these TCFs (control samples)
measured in air at room temperature and a relative humidity RH=45%
are presented in Table 4.
TABLE-US-00004 TABLE 4 Polarizing parameters and color coordinates
of TCF based on 11.5% ink (control samples) measured before baking
Color coordinates Two Two Transmittance, % .DELTA. Single parallel
crossed # T H0 H90 Ep CR (CR) Kd a b a b A b 1 41.6 31.3 3.3 89.8
9.4 0.1 13.4 1.09 -3.94 -2.07 1.65 13.86 -29.81 2 40.0 30.2 1.7
94.4 17.4 0.2 15.1 -0.10 -2.36 -3.54 3.07 14.99 -31.92 3 38.9 29.0
1.2 95.9 24.1 0.4 15.2 -0.30 -1.48 -3.37 3.42 14.79 -30.56 4 38.4
28.4 1.0 96.5 27.8 0.5 15.2 -0.07 -1.55 -2.88 3.06 15.40 -31.46 5
36.4 26.0 0.4 98.4 62.8 2.2 15.8 -1.73 0.49 -4.64 4.35 14.36
-28.44
[0082] In order to increase the thermal stability and improve the
optical properties of TCFs, the samples were treated by dipping for
30 s into various MC+Gl (2:1) solutions at 200 C., followed by
rinsing in DI water and drying with air knife. This treatment
significantly improved the hardness of TCFs. The optical
characteristics of TCFs after impregnation and drying are presented
in Table 5.
TABLE-US-00005 TABLE 5 Polarizing parameters and color coordinates
of TCF based on 11.5% ink measured before baking Color coordinates
Two Two Transmittance, % .DELTA. Single parallel crossed # T H0 H90
Ep CR (CR) Kd a b a b A b Impregnation by 2% MC + 1% G1 solution 6
42.4 32.8 3.2 90.8 10.3 0.1 15.3 0.66 -3.95 -2.84 1.85 14.49 -32.07
7 40.6 31.3 1.7 94.7 18.5 0.2 16.4 0.04 -2.29 -3.40 3.43 15.91
-34.08 8 39.3 29.9 1.0 96.6 29.3 0.5 16.8 -0.40 -1.31 -3.57 3.77
16.30 -33.96 9 39.4 30.0 1.1 96.4 27.6 0.4 16.7 -0.38 -1.22 -3.53
3.88 15.82 -32.75 10 36.5 26.3 0.3 98.9 89.2 4.5 17.1 -1.87 1.19
-4.62 5.01 14.86 -29.07 Impregnation by 4% MC + 2% G1 solution 11
42.8 33.4 3.3 90.6 10.2 0.1 15.9 0.73 -4.06 -2.83 1.84 14.83 -32.77
12 41.1 31.9 1.8 94.6 17.9 0.2 16.9 0.17 -2.39 -3.24 3.42 16.05
-34.49 13 39.6 30.3 1.1 96.3 26.4 0.4 16.8 -0.24 -1.60 -3.45 3.62
16.34 -34.40 14 39.7 30.5 1.0 96.6 29.1 0.5 17.4 -0.63 -1.26 -4.03
3.87 16.54 -33.98 15 38.6 29.1 0.7 97.7 43.6 1.1 17.5 -1.24 -0.20
-4.49 4.47 16.12 -32.46 Impregnation by 6% MC + 3% G1 solution 16
43.2 33.5 3.8 89.1 8.7 0.1 15.1 0.99 -4.35 -2.49 1.91 14.43 -32.67
17 41.0 31.8 1.9 94.3 17.0 0.2 16.5 0.27 -2.60 -3.10 3.16 15.94
-34.23 18 39.1 29.6 1.0 96.5 28.2 0.5 16.4 -0.59 -0.87 -3.92 4.66
16.02 -33.72 19 39.5 30.1 1.0 96.7 29.7 0.5 17.1 -0.77 -1.22 -4.25
3.92 16.53 -34.19 20 39.2 29.9 0.9 97.1 34.5 0.7 17.4 -0.79 -0.85
-4.12 4.34 16.84 -35.20
[0083] Then, the control and (MC+Gl)-impregnated TCF samples were
subjected to heating at 230.degree. C. for 20 min (baking test).
The optical characteristics of TCFs after baking are presented in
Table 6.
TABLE-US-00006 TABLE 6 Polarizing parameters and color coordinates
of TCF based on 11.5% ink measured after baking Color coordinates
Two Two Transmittance, % .DELTA. Single parallel crossed # T H0 H90
Ep CR (CR) Kd A b a b A b Control 1 41.6 30.4 4.2 87.1 7.3 0.1 11.7
0.86 -2.91 -1.91 2.29 10.38 -22.38 2 39.8 29.4 2.3 92.5 12.9 0.2
13.2 -0.18 -1.42 -3.10 3.62 10.55 -22.94 3 38.4 28.1 1.5 94.9 19.2
0.2 13.6 -0.48 -0.50 -3.19 4.16 10.83 -22.56 4 37.7 27.0 1.4 95.1
19.9 0.3 13.0 -0.18 -0.82 -2.64 3.58 10.98 -22.98 5 36.0 25.4 0.6
97.8 45.7 1.2 14.3 -1.70 1.36 -4.24 5.21 9.90 -20.23 Impregnation
by 2% MC + 1% G1 solution 6 42.2 32.1 3.6 89.5 9.0 0.1 13.9 0.88
-3.91 -2.27 1.61 13.06 -29.06 7 39.9 30.0 1.8 94.0 16.3 0.2 14.6
-0.05 -2.01 -3.32 3.50 13.83 -29.87 8 38.7 28.8 1.1 96.1 25.3 0.4
15.2 -0.53 -1.00 -3.60 3.99 14.10 -29.75 9 38.8 29.0 1.2 95.9 24.1
0.4 15.2 -0.49 -0.92 -3.52 4.07 13.71 -28.65 10 36.1 25.6 0.6 97.9
46.0 1.2 14.5 -1.44 0.60 -4.17 4.70 12.48 -25.46 Impregnation by 4%
MC + 2% G1 solution 11 42.5 32.5 3.6 89.4 8.9 0.1 14.3 0.71 -3.42
-2.51 2.26 12.61 -27.85 12 40.6 31.0 2.0 93.8 15.6 0.2 15.4 -0.10
-1.94 -3.48 3.79 13.78 -30.01 13 39.6 30.1 1.3 95.7 22.5 0.3 16.0
-0.36 -1.10 -3.42 4.09 13.83 -29.49 14 39.5 29.9 1.2 96.1 25.0 0.4
16.2 -0.69 -0.68 -3.87 4.37 13.80 -28.58 15 38.3 28.5 0.8 97.2 35.2
0.7 16.2 -1.49 0.45 -4.70 5.20 13.01 -26.56 Impregnation by 6% MC +
3% G1 solution 16 42.5 32.5 3.6 89.4 9.0 0.1 14.3 0.78 -3.59 -2.51
2.44 13.10 -29.56 17 40.6 30.9 2.1 93.5 14.9 0.2 15.1 -0.07 -2.11
-3.48 3.63 13.75 -29.99 18 39.1 29.4 1.2 96.1 24.9 0.4 15.7 -0.69
-0.68 -3.93 4.70 14.10 -30.15 9 39.0 29.2 1.2 96.0 24.8 0.4 15.5
-0.78 -0.96 -4.10 4.14 14.19 -29.81 20 38.0 28.2 0.8 97.3 36.4 0.7
15.9 -1.23 0.13 -4.39 5.01 14.16 -29.35
[0084] Data for the control samples and those impregnated with a 4%
MC+2% Gl solution before and after the baking test are presented in
FIG. 3.
Example 3
[0085] The samples of TCFs on glass substrates were prepared from
12% ink using a Mayer rod as the aligning instrument. The ink was
applied at 20.degree. C. and RH=65-70%. After drying under the same
conditions, the TCF was converted into the water-insoluble form
(Ba-form) by dipping for 1-2 s into a 10% aqueous solution of
barium chloride (BaCl.sub.2). Then, the sample was lifted up in a
vertical position, washed with DI water and dried with air
knife.
[0086] The optical characteristics of these TCFs (control samples)
measured in air at room temperature and a relative humidity RH=45%
are presented in Table 7.
TABLE-US-00007 TABLE 7 Polarizing parameters and color coordinates
of TCF based on 12% ink (control samples) measured before
environmental test Color coordinates Two Two Transmittance, %
.DELTA. Single parallel crossed # T H0 H90 Ep CR (CR) Kd a b A b A
b 1 40.8 30.7 2.5 92.0 12.1 0.1 14.0 0.47 -3.28 -2.52 1.78 12.84
-28.90 2 40.8 31.0 2.3 92.9 13.7 0.2 14.8 0.07 -2.82 -3.12 2.34
12.96 -29.27 3 38.0 28.1 0.8 97.2 34.6 0.7 15.7 -0.73 -0.53 -3.49
3.92 13.74 -29.11 4 37.3 27.3 0.6 97.9 46.1 1.2 15.9 -1.30 0.21
-4.14 4.44 13.58 -28.29
[0087] In order to increase the environmental stability of TCFs,
the samples were treated by dipping for 30 s into a 2.5% MC+1.25%
Gl solution at 20.degree. C., followed by rinsing in DI water and
drying with air knife. This impregnation significantly improved the
hardness of TCFs. The 10 optical characteristics of TCFs after
impregnation and drying are presented in Table 8.
TABLE-US-00008 TABLE 8 Polarizing parameters and color coordinates
of impregnated TCFs based on 12% ink measured before environmental
test: samples were dipped in 2.5% MC + 1.25% Gl solution Color
coordinates Two Two Transmittance, % .DELTA. Single parallel
crossed # T H0 H90 Ep CR (CR) Kd a b A b A b 5 42.1 32.8 2.6 92.3
12.4 0.1 16.1 0.24 -3.13 -3.15 2.60 13.86 -31.50 6 40.9 31.9 1.6
95.0 19.6 0.3 17.3 -0.22 -1.89 -3.54 3.60 14.77 -32.38 7 39.4 30.2
0.8 97.4 38.6 0.8 18.2 -1.07 -0.37 -4.28 4.44 15.49 -32.36 8 38.5
29.0 0.6 98.0 49.2 1.3 17.9 -1.47 0.22 -4.62 4.73 15.07 -31.03
[0088] Then, the control and (MC+Gl)-impregnated TCF samples were
subjected to heating at 80.degree. C. and a relative humidity of
RH=90% for 24 h (environmental test). The optical characteristics
of TCFs after this test are presented in Table 9.
TABLE-US-00009 TABLE 9 Polarizing parameters and color coordinates
of TCF based on 12% ink after environmental test. Color coordinates
Two Two Transmittance, % .DELTA. Single parallel crossed # T H0 H90
Ep CR (CR) Kd A b A B A b Control TCF 1 40.3 29.2 3.3 89.3 8.9 0.1
11.7 -0.75 -3.28 -3.35 2.66 6.65 -27.42 2 39.8 28.8 2.9 90.4 9.9
0.1 11.8 -0.87 -2.71 -3.53 3.16 6.76 -26.63 3 34.5 23.1 0.8 96.7
30.2 0.5 11.6 -1.69 0.83 -4.32 5.87 8.80 -25.09 4 33.0 21.3 0.5
97.8 44.2 1.1 11.5 -2.10 1.74 -4.70 6.43 9.37 -24.82 Impregnation
by 2.5% MC + 1.25% Gl solution 5 41.2 30.8 3.1 90.2 9.8 0.1 13.2
-0.66 -3.64 -3.58 3.06 8.29 -32.55 6 39.7 29.5 2.0 93.4 14.7 0.2
13.8 -1.16 -2.21 -4.40 4.23 9.51 -32.53 7 37.7 27.4 1.0 96.4 27.6
0.4 14.3 -1.74 -0.43 -5.06 5.29 11.21 -32.21 8 36.6 26.0 0.7 97.2
34.8 0.7 14.0 -2.00 0.17 -5.26 5.48 11.41 -31.05
[0089] The plots of contrast versus transmission for the untreated
(control) TCFs and the (MC+Gl)-impregnated samples before and after
the environmental test are presented in FIG. 4.
Example 4
[0090] A supramolecular composite film material was prepared as
follows. An aqueous solution of the mixture of organic compound
including sulfonated derivatives of indanthrone and
perylenetetracarboxylic acid with a total concentration of 5% was
evaporated using a rotor evaporator to a dye concentration of 10%.
After adding surfactant Triton X-100, the resulting working
concentration of the "blue-violet" ink was 7-8%.
[0091] The ink was applied onto the surface of a glass substrate
with simultaneous orientation using a Mayer rod as the aligning
instrument. The film application was performed at 20.degree. C. and
RH=65-70%. After drying under the same conditions, the TCF was
converted into the water-insoluble form (Ba-form) by dipping for
1-2 s into a 10% aqueous solution of barium chloride (BaCl.sub.2).
Then, the sample was lifted up in a vertical position, washed with
DI water and dried with air knife.
[0092] Theoretical characteristics of these TCFs (control samples)
measured at room temperature and a relative humidity RH=45% are
presented in Table 10.
TABLE-US-00010 TABLE 10 Polarizing parameters of TCF based on
<<blue-violet>>inks (control samples) measured before
baking Transmittance, % # T H0 H90 Ep CR .DELTA. (CR) Kd 1 39.68
29.91 1.58 94.8 18.9 15.1 2 38.97 29.06 1.31 95.6 22.2 15.0 3 37.98
28.19 0.66 97.7 43.0 16.5 4 37.53 27.53 0.64 97.7 43.3 16.0 5 36.00
25.51 0.41 98.4 61.6 15.3
[0093] In order to increase the thermal stability and improve the
optical properties of TCFs based on the blue-violet ink, the
samples were treated by dipping for 30 s into a 2.5% MC+1.25% Gl
solution at 20.degree. C., followed by rinsing in DI water and
drying with air knife. This treatment significantly improved the
hardness of TCFs. The optical characteristics of TCFs after
impregnation and drying are presented in Table 11.
TABLE-US-00011 TABLE 11 Polarizing parameters of TCF based on
<<blue-violet>> inks measured before baking (samples
were dipped in 2.5% MC + 1.25% GL solution) Transmittance, % # T H0
H90 Ep CR .DELTA. (CR) Kd 6 40.17 30.85 1.43 95.5 21.6 16.6 7 39.99
30.60 1.39 95.6 22.1 16.4 8 39.88 30.66 1.16 96.3 26.5 17.2 9 38.62
29.08 0.75 97.5 38.9 17.1 10 38.14 28.46 0.63 97.8 45.5 17.0 11
37.18 27.19 0.46 98.3 58.7 16.6
[0094] Then, the control and (MC+Gl)-impregnated TCF samples were
subjected to heating at 230.degree. C. for 20 min (baking test).
The optical characteristics of TCFs after baking are presented in
Table 12.
TABLE-US-00012 TABLE 12 Polarizing parameters of impregnated TCFs
based on <<blue-violet>> ink measured after baking
Transmittance, % # T H0 H90 Ep CR .DELTA. (CR) Kd Control 1 39.04
28.53 1.96 93.3 14.5 13.0 2 38.06 27.02 1.95 93.0 13.8 11.8 3 36.96
26.44 0.88 96.7 30.0 4 36.13 25.31 0.80 96.9 31.5 13.2 5 34.69
23.64 0.43 98.2 55.1 13.5 Impregnation by 2.5% MC + 1.25% Gl
solution 6 39.66 29.86 1.60 94.8 18.7 15.0 7 39.75 30.01 1.59 94.8
18.8 15.2 8 39.62 30.06 1.33 95.7 22.6 16.0 9 38.37 28.62 0.82 97.2
34.9 16.2 10 37.82 27.87 0.74 97.4 37.4 15.8 11 36.77 26.54 0.50
98.1 53.2 15.7
[0095] The plots of contrast versus transmission for the untreated
(control) TCFs and the (MC+Gl)-impregnated samples before and after
the environmental test are presented in FIG. 5.
[0096] The foregoing description of specific embodiments and
examples of the invention have been presented for the purpose of
illustration and description, and although the invention has been
illustrated by certain of the preceding examples, it is not to be
construed as being limited thereby. They are not intended to be
exhaustive or to limit the invention to the precise forms
disclosed, and obviously many modifications, embodiments, and
variations are possible in light of the above teaching. It is
intended that the scope of the invention encompass the generic area
as herein disclosed, and by the claims appended hereto and their
equivalents.
* * * * *