Optical data storage medium having organometallic chromophore/polymer coordinated information layer

Provided is an optical data storage medium comprising a chromophore/polymer composition information layer, wherein the chromophore is chemically bound or coordinated with the polymer. The chromophore is an organo macrocyclic chromophore containing a constituent metal atom, and preferably a central metal atom, with the chromophore being coordinated to the polymer through the metal atom. As a result, the chromophore/polymer material has excellent film-forming properties so that the medium can be readily and efficiently manufactured. As well, the resulting information layer offers excellent thermomechanical properties and exhibits excellent absorption properties, all in a single component material. By utilizing a single component material, the problem of dye/polymer phase separation frequently encountered in conventional dye/polymer mixtures is also overcome.

BACKGROUND OF THE INVENTION 
1. Field of the Invention: 
This invention relates to a novel optical information recording medium and 
the recording of information thereon. More particularly, the present 
invention relates to an information recording medium, preferably in the 
form of a disk or in a tape format, suitable for use with optical 
recording and playback apparatus, with the information layer of the 
recording medium comprising a chromophore/polymer composition. In 
particular, the chromophore is an organo macrocyclic compound having a 
central metal atom, which chromophore is coordinated to the polymer 
through the central metal atom. 
2. Description of the Prior Art: 
Optical recording methods in which light from a laser is focused upon the 
surface of a recording medium with sufficient intensity to cause a 
detectable change in the physical characteristics of the surface material 
have been proposed. Among these methods is the establishment of an 
information pattern of pits. In such methods, the information 
representative pattern of pits may be formed in the surface of the 
recording medium by suitably controlling the intensity of the focused 
light in accordance with the information to be recorded while relative 
motion is established between the recording medium and the focused light 
spot. 
For instance, in recent years, attention has been increasingly paid to the 
information recording method in which information is written in a thin 
film of metal or the like formed on a substrate by using a laser ray or 
beam. According to such a method, the recording of information has been 
accomplished by forming holes or recesses in the metallic thin film under 
the action of an energy beam such as a laser ray. See, e.g., U.S. Pat. No. 
4,238,803. 
The recording medium, of course, is one of the key elements in any optical 
information storage system. The commercial viability of the recording 
medium depends upon such technical parameters as the sharpness in 
recording and playback of the information, i.e., a high signal to noise 
ratio. Dyes and pigments have accordingly been employed in information 
layers, often to enhance the sensitivity of the recording layers at the 
particular wavelength of the laser being used, which results in a much 
sharper recording and playback of information. 
For example, Spong, U.S. Pat. No. 4,097,895, describes a recording medium 
which comprises a light reflecting material, such as aluminum or gold, 
coated with a dye-containing light absorbing layer, such as fluorescein, 
which is operative with an argon laser light source. The thickness of the 
light absorbing layer is chosen so that the structure has minimum 
reflectivity. An incident light beam then ablates, vaporizes or melts the 
dye-containing light absorbing layer, leaving a hole and exposing the 
light reflecting layer. After recording at the wavelength of the recording 
light, maximum contrast between the minimum reflectance of the light 
absorbing layer and the reflectance of the light reflecting layer exists. 
Carlson, in U.S. Pat. No. 3,475,760, discloses a system for directly 
recording information in a thermoplastic film as a deformation by using a 
high energy laser scanning beam of small diameter. It is further disclosed 
that the sensitivity of the films for laser film deformation recording can 
be enhanced by the addition of pigments or dyes which exhibit a high 
absorption at the laser wavelength. Erasure of the film deformation is 
accomplished by recording over the information to be erased using a 
similar laser beam but with a much smaller scan line spacing, preferably 
so as to provide overlap of the scan lines. 
Other U.S. patents which disclose the use of a light absorbing dye in the 
recording layer include U.S. Pat. Nos. 4,412,231 and 4,446,223. The former 
patent discloses using a mixture of dyes having different light absorbing 
wavelengths so that the resulting recording layer has a light absorptivity 
of 80% or more at all the wavelengths in the range of from 400-900 nm. The 
latter patent discloses an optical information recording element 
comprising a support coated with a layer of an amorphous composition, 
which composition comprises a binder and an oxoindolizine or 
oxoindolizinium dye. 
In a paper entitled "Single Wavelength Optical Recording in Pure, Solvent 
Coated Infrared Dye Layers" by Gravesteijn, Steenbergen and van der Veen, 
experiments on the use of certain dyes for optical recording for digital 
and video applications at GaAlAs laser wavelengths are reported. The paper 
was presented at the Proceeding of the SPIE, "Optical Storage Media", 
volume 420, June 6-10, 1983. The specific dyes discussed in the paper are 
squarylium dyes and pentamethine dyes. It is further suggested that 
solubility in organic solvents can be greatly increased by the 
introduction of t-butyl groups into thiapyrylium end groups. 
The use of dyes in conjunction with optical recording media comprising a 
styrene oligomer is disclosed in the article by Kuroiwa et al appearing in 
the Japanese Journal of Applied Physics, Vol. 22, No. 2, February, 1983, 
pp. 340-343. Among the dyes and pigments discussed as being useful is a 
copper phthalocyanine pigment. Phase separation and incompatibility 
between the dyes and oligomers are noted in the article as being problems 
in the use of dyes for optical information media. 
The use of other metal phthalocyanine dyes in optical recording media is 
disclosed, for example, in U.S. Pat. No. 4,458,004. Note also, U.S. Pat. 
No. 4,492,750, which discloses the use of specific naphthalocyanine 
compounds in optical recording media. The film-coating properties of such 
dye materials, however, have been generally found to be poor, the read out 
Signal/Noise (S/N) ratio poor and tending to fluctuate depending on the 
particular portion of the layer, and the S/N ratio of the read-out 
deteriorating significantly after repeated irradiations of the read-out 
light. 
Horiguchi et al, U.S. Pat. No. 3,637,581, discloses chromogen-bonded 
polymers, with the chromogen possibly being a metal phthalocyanine. The 
suitability and use of such products in optical mass data storage 
applications, however, are not disclosed therein. 
Thus, while dyes or pigments have been employed in the information storage 
layers of optical recording media due to their excellent absorption 
properties, problems are encountered with regard to the application of the 
dyes or pigments as a stable layer. The addition of dyes to film-forming 
polymers due to limited solubility of the dye in the polymer and the 
tendency of the dye/polymer mixture to phase separate over time, as noted 
above, are severe problems which need to be overcome. Indeed, the higher 
the pigment or dye concentration, the more likely such problems are 
encountered. Yet, it is desired to increase the dye concentration in the 
information layer so as to increase the sensitivity of the medium, the 
recording rate possible and the S/N ratio upon read-out. 
The search for an improved information storage medium comprising a dye or 
pigment overcoming the aforementioned problems is thereby continuously 
ongoing. What is desired is a recording layer material which of course 
exhibits a high extinction coefficient, but which also exhibits excellent 
film-forming properties to enhance its coating applicability, and good 
solubility in solvents for ease of manipulation. With such properties, the 
commercial viability and exploitation would be greatly enhanced. 
Otherwise, mass production would be too difficult to render the medium 
commercially plausible on a large scale. A recording medium which further 
eliminates the problem of phase separation over time would also be most 
desirable. Excellent stability with respect to thermal, actinic and 
oxidative degradation is also a desirable feature. 
Accordingly, it is a major object of the present invention to provide a 
novel and improved recording medium which comprises a chromophore in the 
information layer. 
It is yet another object of the present invention to provide a novel 
optical recording medium which allows for ready application of the 
chromophore layer to form a stable information layer, while still 
exhibiting excellent absorption properties. 
Still another object of the present invention is to provide a novel 
recording medium which contains a chromophore in the information layer, 
yet for which the problem of phase separation over time frequently 
encountered in dye/polymer mixtures is eliminated. 
Yet another object of the present invention is to provide a one-component 
material for use in an information layer of an optical recording medium 
which exhibits excellent film-forming and thermomechanical properties, and 
excellent absorption properties. 
These and other objects, as well as the scope, nature and utilization of 
the invention, will be apparent to those skilled in the art from the 
following description and the appended claims. 
SUMMARY OF THE INVENTION 
In accordance with the foregoing objectives, provided hereby is a medium 
for storage of optical information, i.e., information recorded and played 
by optical means, which medium comprises a chromophore/polymer composition 
wherein the chromophore is chemically coordinated with the polymer. The 
chromophore is an organo macrocyclic chromophore containing a constitutent 
metal atom, preferably being a central metal atom, through which the 
chromophore is chemically coordinated to the polymer. 
The most preferred chromophores for use in the present invention are 
aza-annulenes, e.g., phthalocyanines, naphthalocyanines, porphyrins, 
substituted porphyrins, tetrabenzoporphyrins, and 
tetranaphthaloporphyrins. The preferred constituent metals are Ge, Sn, Al, 
Ga, In, alkaline earths, lanthanides, actinides or transition metals. It 
is most preferred that the constituent metal be a central metal atom with 
the most preferred central metals being the transition metals. The 
preferred polymer to which the chromophore is chemically coordinated is a 
dimer acid polyamide or poly(vinylpyridine). 
In a most preferred embodiment, the medium for storage of optical 
information is in the form of a disk. Furthermore, the medium is erasable. 
In another embodiment of the present invention, there is provided a method 
of recording information in a thin film deposited on a relatively thick 
substrate by irradiating the film with a laser beam in accordance with 
said information to form pits in the film, the improvement which comprises 
said film being comprised of a chromophore/polymer composition wherein the 
chromophore is an organo macrocyclic chromophore containing a constituent 
metal atom, and preferably a central metal atom, with the chromophore 
being chemically coordinated to the polymer through the central metal 
atom. 
In another embodiment there is provided by the present invention a readable 
information medium comprising a relatively thick and thermally stable 
substrate having coated thereon a layer comprising an information track 
comprised of a chromophore/polymer composition. The chromophore of the 
composition is an organo macrocyclic chromophore containing a constituent 
metal atom, and preferably a central metal atom, with the chromophore 
being chemically coordinated to the polymer through the central metal 
atom. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The recording or information layer of the optical data storage medium of 
the present invention comprises the chromophore/polymer composition. The 
chromophore is chemically coordinated to the polymer so that the 
composition is essentially a one-component system. 
The chromophore is an organo macrocyclic chromophore containing a 
constituent metal atom. Examples of suitable chromophores for the present 
invention include aza-annulenes, bis dithiolates. The metal dye complexes 
as disclosed in The Chemistry of Synthetic Dyes, by V. Venkataraman, Vol. 
I, 1952, Chapter XIV, pp. 551 et seq. An example of a non-symmetrical 
chromophore complexing with a polymer to form a chromophore/polymer 
composition in regard to the present invention is a composition of the 
following units: 
##STR1## 
wherein R is a direct chemical bond, aliphatic radical having from 2 to 12 
carbon atoms, an alkylene of 3 to 10 carbon atoms or aryl. In general, any 
chromophoric compound with a constituent metal atom, and preferably a 
central metal atom through which coordinate bonding can occur with the 
selected polymer can be utilized for the present invention. 
Substitution of the chromophores can be to any extent practicable, the 
determining factor being the ultimate performance of the 
chromophore/polymer material as the recording layer in an optical 
recording medium. Generally, when substitutions are employed, the number 
and type of substitutions are chosen so that the absorption maximum for 
the material corresponds with the output wavelength of the laser used in 
the optical recording. The thermomechanical properties of the material 
should also allow data to be recorded on the recording layer by a focused 
laser beam operating above a threshold power value for writing data and at 
a useful data rate. The data can then be read by a focused, but lower 
power, laser beam that causes no detrimental change in the signal obtained 
from the recording layer. The excellent absorption characteristics of the 
recording layer material allow the data to be read by changes in 
reflectivity. The thermomechanical properties of the chromophore/polymer 
composition material can also be effected by the number (and type) of 
substitutions to allow laser addressed erasure of the data and to allow a 
film of the material to be cast by any technique known to those skilled in 
the art of coating. In general, therefore, when substituents are employed, 
the effect of the substituents of the chromophore should be carefully 
considered so that they are selected to achieve the desired spectroscopic, 
thermomechanical and film-forming properties. 
The constituent metal atom of the chromophore can be any metal through 
which coordinate bonding with the polymer can occur. In general, however, 
it is preferred that the metal atom be Ge, Sn, a transition metal, Al, Ga, 
In, an alkaline earth, lanthanide, or actinide. It is most preferred for 
purposes of the present invention that the metal atom be a central metal 
atom, in which case the transition metals are most preferred. 
Non-symmetrical chromophore compounds wherein the metal atom is not 
central, as noted previously, are contemplated within the scope of the 
present invention. 
The preferred organo macrocyclic chromophore for the purposes of the 
present invention is an aza-annulene containing a central metal atom. The 
preferred aza-annulene chromophores are phthalocyanines, 
naphthalocyanines, tetrabenzoporphyrins or substituted or unsubstituted 
porphyrins. The naphthalocyanines are preferred for use with systems 
employing a diode laser, i.e., wavelength from 750-900 nm. Whereas the 
phthalocyanines are preferred when the system laser is a He-Ne laser, 
i.e., wavelength about 633 nm, tetrabenzoporphyrins when the laser 
wavelength is about 488 nm, i.e., an Argon laser, and porphyrins when a 
frequency-doubled diode laser is used, wavelength about 410 nm. Thus, the 
preferred chromophore materials in any particular instance is that 
absorbing sufficiently at the wavelength of the laser used in the 
write/read system to be employed. 
The macrocyclic portion of the chromophore, as discussed above, can also be 
substituted with various substituents, preferably selected to influence 
the absorption spectrum of the recording layer. The substituents may be 
chosen such that the absorption maximum of the recording layer closely 
corresponds to the wavelength of light used in the recording, erasing, and 
in most cases, the reading processes. These substituents may also 
contribute to the ability of the material to be film forming. 
The most preferred aza-annulenes for use with a diode laser are the 
naphthalocyanines having the following structural formula with any isomers 
thereof being contemplated for the purposes of the present invention: 
##STR2## 
wherein the X substituents are independently selected organic or inorganic 
substituents and can be the same or different, with n and m indicating the 
number of independently selected X substituents, each n being the same or 
different and ranging from 0 to 4, and each m being the same or different 
and ranging from 0 to 2. The substituents X in particular can be alkyl, 
halo, hydroxy or any other conventional substituent for such chromophores. 
As discussed previously, however, the number and type of X substituents, 
when employed, are generally selected to effect the absorption and 
thermomechanical properties of the final recording layer. Y is the central 
metal atom. 
The polymer to which the chromophore is coordinated is preferably a polymer 
having good film-forming and thermochemical properties so that it can be 
effectively employed in an optical information medium, and which has a 
suitable site for chemical coordination to the constituent metal atom of 
the chromophore. Of course, if the chosen polymer does not have a suitable 
reactive site for coordination with the metal of the chromophore, reactive 
moieties can generally be reacted with the polymer to provide a product 
having suitable pendant reactive moities. 
In general it has been found most desirable to employ polymers having 
reactive heterocyclic amine moieties or certain ionic moieties which may 
either be incorporated into the backbone of the polymer or attached to the 
polymer as pendant groups. Particularly effective heterocyclic amine 
moieties include imidazolines, pyridines and imidazoles. Preferred ionic 
moieties include thiolates and carboxylates. 
Examples of suitable polymers are the dimer acid polyamides, polyamides, 
poly(vinylpyridine), polyurethanes, polyesters, silicones and vinyl 
polymers such as styrene polymers. The preferred polymers are dimer acid 
polyamides and poly(vinylpyridine). Of particular preference are the dimer 
acid polyamides Emerez 1565 and Emerez 1514, e.g., as disclosed in U.S. 
Pat. No. 4,478,782, which is hereby expressly incorporated by reference. 
Once the polymer has been synthesized, it can be reacted directly with the 
chromophore by conventional reaction procedures to yield the one-component 
composition. Generally, the reaction is controlled so that the amount of 
chromophore incorporated into the polymer comprises less than 25% by 
weight of the material. Functionally, of course, the lower limit of the 
amount of the chromophore incorporated is determined by the suitable 
optical absorption properties of the material. The upper limit of the 
amount of chromophore incorporated is determined by the desired 
thermomechanical properties exhibited by the material. 
The chromophore/polymer material of the subject invention allows one to 
realize the excellent absorption properties of the chromophore, e.g., high 
extinction coefficient, while also realizing the benefits of the 
thermomechanical properties of a film-forming material as a result of the 
film-forming properties arising from the polymeric base. As well, since a 
single component material is used, the problem of dye/polymer phase 
separation is avoided. Chemically coordinating the chromophore to the 
polmer also allows much higher effective chromophore concentrations in the 
recording layer than simple solutioning of a dye in a polymer. The result 
is increased sensitivity so data recording is possible with lower laser 
power at faster speeds. 
Coordination through the constituent metal atom has also been discovered to 
be surprisingly advantageous with regard to the marking properties of the 
composition. During laser recording, the relatively weak metal-polymer 
bond breaks, thereby lowering the viscosity of the material. Upon cooling, 
however, the bond reforms and the morphology of the polymer is again set 
for the chromophore. The practical result of this phenomenon is more 
control over writing and erasing of information as one has a very sharp 
threshold, i.e., difference between power needed for writing and not 
writing. Moreover, in the bonded state after writing, the composition 
exhibits good stability against creep and pit deformation. Therefore, the 
archival life is good. Overall the result is an information layer 
exhibiting an excellent combination of absorption and thermomechanical 
properties permitting one to easily mark and maintain an information 
record, while also allowing one to easily apply the material as a film in 
manufacturing the optical medium. 
The film formed by the chromophore/polymer material of the present 
invention may be self-supporting, in which case any suitable or 
conventional casting technique may be used. Generally, however, it is 
preferred to cast the material as a film on a suitable support to add 
dimensional stability and support thereto. As well, the film may not 
always be self-supporting. The substrate may be optically featureless or 
may contain preformatting information (e.g., tracking groove and/or 
encoded information in the form of readable marks.) It is important when 
coating a substrate, of course, that an extremely flat homogeneous 
information recording surface be obtained to preclude the scattering of 
light. 
Any suitable coating technique may be used to achieve such a flat surface, 
with a conventional technique such as spin coating, which allows for a 
high degree of control of film thickness and flatness, being preferred. It 
is, of course, desired and preferred that the one-component material form 
a thin film coating. 
The substrate which is coated with the chromophore/polymer material should 
generally possess a surface of suitable smoothness. This may be imparted 
by appropriate molding or other forming techniques when the substrate is 
made. If the substrate has an inadequately smooth surface, a smoothing or 
subbing polymer layer may be used to attain the appropriate smoothness. 
Such a smoothing or subbing layer should not, of course, interfere with 
application or utilization of the recording layer which is subsequently 
applied thereto. The subbing layer can contain preformatting information. 
The material of which the substrate is comprised is generally a material 
exhibiting good structural integrity against warping and mechanical 
strength. Examples of suitable materials include aluminum, glass, 
reinforced glass, ceramics, polymethacrylates, polyacrylates, 
polycarbonates, phenolic resins, epoxy resins, polyesters, polyimides, 
polyether sulfones, polyether ketones, polyolefins, polyphenylene sulfide 
and nylon. Furthermore, the shape and size of the substrate, and hence the 
recording medium, can vary depending on the application. The shape and 
format, for example, may be a disk, tape, belt or drum. A disk shape or 
tape format is most preferred. 
The structure of the recording medium itself may also vary in that the 
recording layer may be coated on one side or both sides of the substrate. 
Or, two substrates having the recording layer on either side can be 
combined allowing the sides having the recording layers to face each other 
at a constant distance, the combined substrates being sealed to prevent 
dust contamination and scratches. 
The medium of this invention may also have an undercoating layer such as a 
metal reflective layer or layer of various resins on the substrate if 
necessary, with the recording layer being coated over it. In addition, 
various thermoplastic resins, thermosetting resins, UV or electron beam 
cured resins, may be used as an undercoating material. Furthermore, it is 
possible to laminate layers from the substrate as follows: a reflective 
layer, undercoating layer and recording layer. The film thickness of the 
recording layer may be designed to be non-reflective if desired. 
In addition, guiding grooves may be installed on the substrate, and the 
recording layer may be installed on the extruded portions and/or intruded 
portions of the grooves. Furthermore, if necessary, a reflective layer or 
opaque layer may be installed over the recording layer. 
A suitable protective layer or cover, such as those known to the art, can 
also be used if desired to protect the recording layer from dirt, dust, 
scratches or abrasion. 
In addition to the chromophore/polymer composition, the recording layer may 
also contain other polymers or oligomers, various plasticizers, 
surfactants, antistatic agents, smoothening agents, flame retardants, 
stabilizers, dispersants, leveling agents, antibleeding agents, 
antioxidants, water repellents, emulsifiers, etc. as may be desired. The 
effect the presence of such additives may have on the optioal properties 
of the medium, however, should be taken into account. 
In an illustrative recording system embodying the principles of the present 
invention, a record blank disk form may be subject to rotation at a 
constant linear or constant angular velocity while a beam of light from a 
light source, e.g., a laser, is focused on the information surface of the 
disk. The wavelength of the light being compatible with the absorption 
characteristics of the chromophore/polymer composition of which the 
recording layer is comprised. The intensity of the light beam is 
controlled in accordance with the information to be recorded. 
Illustratively, the control is effected in accordance with carrier waves 
modulated in frequency by information containing signals, with the light 
beam intensity varying as a result between a high level sufficient to 
effect a detectable change in the physical characteristics of the 
absorptive one-component recording layer material and a low level 
insufficient to effect such a detectable change, the frequency of the 
level alternations varying as the signal amplitude changes. Preferred 
writing speeds are in the range of from 10.sub.6 to 10.sub.7 bits per 
second. 
The relative diameter and depth of the holes or pits formed will, of 
course, depend not only on the optical and thermal properties of the 
one-component information layer, but also on the characteristics of the 
writing beam, i.e., focused spot diameter, depth of focus, intensity 
profile and intensity and duration of the writing pulse. Optimization of 
these parameters is familiar to those skilled in the art. 
As a result of the pit-formation in the recording layer material, an 
information track comprising a succession of spaced pits is formed in the 
information surface of the disk, the pits appearing in those surface 
regions exposed to the high intensity beam. Variations in the length and 
separation of the pits are representative of the recorded information. 
The result of the above-described recording process is the formation of an 
information record of a form which facilitates recovery of the recorded 
information by optical playback processes. The information track of such 
an information record comprises (1) undisturbed surface regions 
alternating with (2) pit regions formed by the pit-forming process, 
preferably coated on a substrate. This information track can be in either 
analog or digital form, for example, audio, video or computer data. 
In playback or read operations pursuant to the principles of the present 
invention, a light beam is focused upon the information track of an 
information record. The playback beam has a constant intensity at a level 
insufficient to effect pit formation in the information layer or erasure 
of the recorded information by levelling. A photodetector, positioned to 
receive light reflected from the successive regions of the information 
track as they pass through the path of the focused light, develops a 
signal representative of the recorded information. 
Several variations in the playback or reading system as known to the art 
are possible. The most preferred mode of reading information involves the 
relative reflection between the one-component material surface and those 
areas in which pits have been formed in the recordation of information. 
When the reflectivity of the one-component material surface is of 
relatively high reflectivity as compared to that of the substrate or other 
underlying layers, the reflectivity in the areas of the pits will be less 
than in the regions without pits when a beam from the read laser passes 
thereby Thus, a written bit can be registered as a decrease in reflected 
intensity. When the relative reflectivity of the one-component material 
surface is low as compared to that of the substrate and other underlying 
layers, however, the reflectivity in the areas of the pits will be more 
than in the regions without pits when a beam from the read laser is 
focused thereon. Accordingly, a written bit can be registered as an 
increase in reflected intensity. 
An advantage of the present invention is that the resulting information 
medium can also be suitable for erasure. The selection of polymer and 
substituents on any particular chromophore will have a profound effect on 
the erasability of the medium. Generally, complete and accurate erasure of 
recorded information can be readily carried out by heating the medium to a 
sufficiently high temperature such that the chromophore/polymer 
one-component material becomes softened sufficiently to allow levelling of 
the surface. This can be done globally by heating the entire disk in an 
oven or some other suitable heating means, or by means of a defocused 
laser beam whose intensity at the surface of the information layer is 
intermediate between that of the write beam and read beam. It is generally 
necessary to heat an area greater than that of a single bit (typically 1 
.mu.m in diameter).

The present invention is further illustrated by the following examples. The 
details of the following examples, however, are in no way meant to be 
limitative, but rather merely illustrative. 
The following examples pertain to the preparation of chromophore/polymer 
compositions useful in optical data storage media in accordance with the 
present invention. The chromophore employed in each example is ruthenium 
phthalocyanine or vanadyl phthalocyanine and the polymer base a poly(vinyl 
pyridine) or dimer acid polyamide. The procedures exemplified, however, 
would be workable for other metal containing organic macrocylic compounds, 
particularly metal phthalocyanines, naphthalocyanines and 
tetrabenzoporphyrins. Other polymers than the poly(vinyl pyridine) and 
dimer acid polyamides exemplified should also be readily substituted by 
the skilled artisan. 
The first two examples simply demonstrate the chemical coordination of a 
transition metal phthalocyanine chromophore to a suitable polymer. 
EXAMPLE 1 
0.0116 g of ruthenium phthalocyanine was mixed with 0.2295 g of 
poly(4-vinylpyridine). 2.9304 g of n-butanol and 1.7 g of 1,2 
dichloroethane were added to the mixture. The polymer did not dissolve in 
the solution, but the ruthenium phthalocyanine did dissolve to give a deep 
blue solution. Upon sonication (i.e., subjecting the mixture to ultrasonic 
irradiation), the polymer seemed to swell and turn blue as the chromophore 
became coordinated to the 4-vinyl pyridyl residues of the polymer 
structure. The mixture was allowed to stand for about 1/2 hour and then 
the blue butanol solution was decanted from the deep-blue polymer. The 
polymer was then washed three times with 2 ml of fresh n-butanol to remove 
excess ruthenium phthalocyanine. After the third washing the butanol was 
colorless, while the poly(4-vinylpyridine) was still a deep-blue color. 
This indicated that the chromophore was at least sufficiently coordinated 
with the polymer to not be extracted by the n-butanol. 
EXAMPLE 2 
0.1141 g of poly(4-vinylpyridine) was dissolved in 12.4049 g of toluene 
with sonication. A small amount, i.e., about 25 to 50 mg, of ruthenium 
phthalocyanine was added to the colorless solution. The ruthenium 
phthalocyanine chromophore was not soluble in the toluene and settled to 
the bottom of the solution. Upon sonication, however, small amounts of the 
chromophore appeared to dissolve in solution as the solution turned blue. 
After continued sonication all the ruthenium phthalocyanine became 
dissolved in the solution and wa believed to be held in solution through 
coordination to the poly(4-vinylpyridine). Addition of about 2 ml of water 
caused some of the polymer to precipitate from the toluene and settle at 
the interface between the toluene (top phase) and the water (bottom 
phase). Some polymer remained in the toluene solution as indicated by the 
blue top phase, which is the result of the ruthenium 
phthalocyanine/poly(4-vinylpyridine) coordination. The water phase 
remained colorless. 
The next two examples demonstrate the preparation of transition metal 
phthalocyanines/dimer acid polyamide compositions. The phthalocyanine is 
coordinated to the polymer through its central metal atom and the 
imidazolidine functional moiety of the polymer. 
EXAMPLE 3 
About 30 mg of Emerez.RTM.-1565 (a dimer acid polyamide available from 
Emery Industries) was dissolved in 3 ml of a saturated solution of a 
ruthenium phthalocyanine in n-butanol. The mixture resulted in a deep blue 
solution. About 1 ml of distilled water was then added to the butanol 
solution, with a slimy white material phase thereby becoming separated as 
a water phase. The butanol and water phases were immiscible, with the 
butanol forming a top blue phase. The mixture was allowed to sit 
overnight, with no further separation occurring. 
EXAMPLE 4 
In this example, N,N-dimethylformamide was utilized as a solvent as opposed 
to the n-butanol in Example 3. 
A small piece, about 20 mg, of Emerez.RTM.-1565 was placed in a saturated 
solution of ruthenium phthalocyanine in N,N-dimethylformamide. The mixture 
was sonicated for about one minute. The polymer did not appreciably 
dissolve. Close visual examination of the polymer indicated some blue 
color, indicating possible reaction with the ruthenium phthalocyanine. The 
mixture was allowed to stand overnight. 
The next day the solution was decanted off with a disposable pipette and 
the polymer was rinsed with two 2 ml portions of N,N-dimethylformamide to 
remove excess ruthenium phthalocyanine. The polymer was a deep blue color 
that persisted after repeated washings with the N,N-dimethylformamide, 
thereby indicating coordination of the chromophore to the polymer in 
accordance with the subject invention. 
EXAMPLE 5 
0.446 g of Emerez.RTM.-1565 polymer was dissolved in 1.3953 g of n-butanol 
solvent after stirring and heating to about 100.degree. C. Upon allowing 
the solution to cool to about 50.degree. C., 0.4705 g vanadyl 
phthalocyanine was added to the viscous polymer solution. The mixture was 
agitated by hand, sonicated for about 30 seconds, and then allowed to stir 
overnight at room temperature. The solution was a deep purple. 
The next day the solution was an opaque-black color which was taken up in a 
gas tight syringe and filtered through a 13 mm diameter 5 .mu.m pore size 
millipore filter. About 1/2 ml of a dark brown solution was filtered, 
which color change indicated the reaction between the vanadium 
phthalocyanine and Emerez.RTM.-1565 dimer acid polyamide. 
The foregoing run was repeated on a larger scale. 3.2 g of Emerez.RTM.-1565 
polymer was completely dissolved in 47.81 g of n-butanol upon stirring and 
heating to about 100.degree. C. 2.813 g of vanadium phthalocyanine was 
then added to the solution. The result was a deep purple slurry which was 
allowed to stir at 90.degree. C. for about three days. The mixture was 
then allowed to cool to room temperature, and filtered through a 1.2 .mu.m 
millipore filter using a pressure filter. The filtrate was a khaki color, 
which a considerable amount of purple powder was retained on the filter. 
The filtrate was concentrated to a viscous mass that was mechanically 
removed from the round bottom flask. The last traces were rinsed out with 
some n-butanol. The butanol was further removed by heating to about 
150.degree. C. on a watchglass to give a khaki green molten polymer 
solution. The material was allowed to cool on the watchglass to a solid 
film and then dried at high vacuum overnight at 60.degree. C. 
Samples of the vanadyl phthalocyanine/dimer acid polyamide composition were 
tested by DSC-TMA, IR spectra, and Electronic Absorption Spectra 
techniques. The results from the IR spectra were not informative. The 
results of the DSC-TMA and Electronic Absorption Spectra tests are as 
follows: 
Twenty-three percent (by weight) of vanadyl phthalocyanine was coordinated 
in the polymer. The thermal properties of the composition indicated two 
thermal transitions: 
DSC: T(melt,1) 48.degree. C.; T(melt,2) 83.degree. C. 
TMA: T(soften,1)=50.degree. C.; T(soften,2)=84.degree. C. 
The polymer without any vanadyl phthalocyanine had the thermal properties: 
T(melt)=54.degree. C.; T(soften)=52.degree. C. 
This indicated that the reaction of the chromophore with the coordinating 
polymer changed the physical properties of the material. 
The Electronic absorption spectrum was taken in n-butanol, and it showed 
two absorption maxima: 
(i) a strong absorption at 685 nm, and 
(ii) a weaker absorption at 800 nm. 
Thus, the dye loading of the foregoing polymer composition is quite high. 
Moreover, the chromophore/polymer composition is quite homogeneous. Its 
high solubility in organic solvents such as n-butanol also facilitates its 
coating and subsequent film-forming by such conventional techniques as 
spin coating. 
EXAMPLE 6 
In the example, a dimer acid polyamide useful for coordination purposes of 
the present invention was synthesized. Then, hypothetically, coordinated 
with a dye and spin coated onto a suitable substrate for use as an optical 
mass data storage medium. 
Step A: Preparation of the coordinating monomer 
N-[2(4-pyridyl)-ethyl]ethylene diamine. 
This was an adaptation of the procedure reported by R. G. Lacoste and A. E. 
Martel in Inorganic Chemistry 1964, 3(6), 881, for the preparation of 
N-[2-(4-pyridyl-ethyl]ethylene diamine. To a 250 ml three neck round 
bottom flask, fitted with a dropping funnel, a reflux condenser, and 
magnetic stirring, was added 12.02 g (0.2 mol) ethylene diamine, 24 g 
distilled water, and 31.50 g (0.3 mol) freshly distilled 4-vinylpyridine. 
The temperature was maintained at 20.degree.-30.degree. C. while 12.0 g 
glacial acetic was added through the dropping funnel. After all the acetic 
acid was added, the reaction mixture was heated on the steam bath for two 
hours. The product was fractionally distilled to give 11.48 g (35% yield). 
The product was characterized by IR and NMR. 
Step B: Preparation of the dimer acid polyamide polymer. 
To a 500 ml three neck round bottom flask, fitted with mechanical stirring, 
a Dean-Stark moisture receiver and reflux condenser, and dry N.sub.2 
purge, was added 102.24 g (0.18 mol) Empol-1010 (dimer acid purchased from 
Emery Industries, Cincinnati, Ohio), 8.87 g (0.148 mol) ethylene diamine, 
and 5.95 g (36 mmol) N-[2-(4-pyridyl)-ethyl]ethylene diamine. The mixture 
was slowly heated with stirring under N.sub.2 to 250.degree. C. over the 
period of two hours and then held at 250.degree. C. for an additional two 
hours. After two hours at 250.degree. C., the reaction mixture was 
distilled under high vacuum at 250.degree. C. for 2.5 hours to remove (7.6 
g) water (and other volitiles) formed during the condensation 
polymerization. This gave 109 g of a coordinating dimer acid polyamide 
which was shown by NMR to contain one pyridine residue per every 12 dimer 
acid residues. 
Step C: Coordination with chromophore and spin coating. 
The polymer (4.0 g), made in step B, is dissolved in 16.0 g n-butanol with 
stirring and gentle heating (T&lt;100.degree. C.). After all the polymer has 
dissolved, 0.75 g of Oleosol Fast Blue (a copper phthalocyanine dye 
available from Sumitomo Chemicals) is added to the stirring polymer 
solution. The blue solution is allowed to stir at room temperature 
overnight. It is assumed that all the dye goes into solution and 
coordinates with the polymer. The next day the solution is filtered 
through a 0.5 micron pore size Millipore membrane filter to remove any 
insoluble materials. The solution is then cast on glass or polymer 
(polymethyl methacrylate or polycarbonate) substrates using a spin coater, 
e.g., a Headway model EC101D spin coater. The films are then thoroughly 
dried in a vacuum oven at 60.degree. C. for two hours to remove any 
residual solvent. 
Although the invention has been described with preferred embodiments, it is 
to be understood that variations and modifications may be resorted to as 
will be apparent to those skilled in the art. Such variations and 
modifications are to be considered within the purview and the scope of the 
claims appended hereto.