DE19753025B4 - Optical data storage and method for its production - Google Patents

Abstract

worin die Gruppen R₁, R₂, R₃ entweder
• ein Wasserstoffatom bedeuten oder
• R₁ einen beliebigen Alkylrest und R₂, R₃ ein Wasserstoffatom darstellen oder
• R₁ ein Wasserstoffatom und R₂, R₃ einen unsubstituierten oder
• substituierten Arylrest bedeuten und Me entweder
• zwei Wasserstoffatome oder
• ein Metall bzw. Schwermetall oder
• ein Halogenmetall oder
• eine Hydroxy- bzw. Alkoxymetallgruppierung oder
• eine Oxymetallgruppe
bedeutet.Optical data storage containing organic dyes with different wavelength-selective species,
marked by
Metal complexes, including metal-free compounds of anthraannulated porphyrazines, which have a number of transannular endoperoxide bridges in the fused anthracene part, according to formulas I, II, IIIa or IIIb, IV or V,

wherein the groups R ₁ , R ₂ , R _{3 are} either
• represent a hydrogen atom or
• R _{1 is} any alkyl radical and R ₂ , R _{3 represent} a hydrogen atom or
• R _{1 is} a hydrogen atom and R ₂ , R _{3 is} an unsubstituted or
• substituted aryl radical and Me either
• two hydrogen atoms or
• a metal or heavy metal or
• a metal halide or
• a hydroxy or Alkoxymetallgruppierung or
• an oxymetallic group
means.

Description

The The invention relates to an optical data storage, the organic Contains dyes with different wavelength-selective species and on a method for producing such a data memory. at the dyes of the type according to the invention are Anthracannulated porphyrazines in the fused anthracene part transannular endoperoxide bridges in different numbers.

Such organic compounds are known, for. B. from the DD 226 288 A1 (Anthracene-fused Metalltetraazaporphine as catalysts for electron transfer reactions or as organic conductors) and, more recently, a tetraanthraporpyrazine from: "Journal of Photochemistry and Photobiology, B: Biology" Vol. 30, 1995, pages 77-78; "Journal of Information Recording Materials "(1996) Vol. 23, pages 167-169; "Tetrahedron Letters", Vol. 37, No. 29 (1996), pp. 5083-5086 and "Journal of Photochemistry and Photobiology; A: Chemistry" Vol. 105 (1997) pp. 153-158.

The Metal complexes of the above-mentioned anthracene-fused tetraazaporphyrins absorb in the near infrared between, 800 nm and 1000 nm, wear but no transannular endoperoxide bridges. On the other hand that is in the listed above Porphyrazine, the endoperoxide bridge in different number n (n = 0, 1, 2, 3, 4) can carry there disclosed only as its palladium complex. At this connection are absorption maxima in the range between about 650 nm and 850 nm. As intended use this porphyrazine is photodynamic tumor therapy (PDT) intended. From this point of view, there are the requirements for a such material in it, by photooxidation of a starting molecule to a Oxygen donor to get the oxygen gradually back emits. So far it has not been possible other metal complexes or metal-free compounds of anthracannulated Porphyrazines as the octaphenyltetraanthraporphyrazinato-palladium to represent as an oxygen donor.

in the Frame in recent Time under the term "molecular engineering " and interdisciplinary Work that deals with the optimization of molecules or molecular ensembles to deal with specific properties, take the developments in the field of data processing. The Density of processed data and data processing speed are still rising with decreasing hardware requirements and to be expended Costs. Electro-optical or photonic components (lasers, photodiodes) To send / write or receive / read data includes both in the relevant investment as well as consumer goods industry to the meanwhile usual Equipment of modern devices, in which optical record carrier / data storage is used become. Their price / performance ratio also develops consumer-friendly.

The z. For example, as described in Science, Vol. 245 (August 25, 1989), pages 843-845, three-dimensional optical memories are intended to allow rapid random access to the high-density data (6.5 × 10 ¹² bits / cm ³ ) Writing and reading are carried out by means of two temporally and spatially overlapping laser beams, respectively, and quenching can be effected by temperature influence. As the photochromic material, spirobenzopyran embedded in a polymer matrix is used, which is initially in the spiropyran form only in the ultraviolet region Simultaneous two-photon excitation converts the material into the merocyanine form, which absorbs in the green / red region of the visible spectrum and fluoresces red-shifted upon green excitation.

When technical problem of the already mentioned above "molecular engineering" is - from here acknowledged State of the art starting - the Question to see if there is a possibility in place of previously used organic dyes, only in two different Species exist and for three-dimensional optical data storage are suitable, based on another known, first for photodynamic tumor therapy intended material with four photochromic, gradual oxygen-releasing species predominantly, but not exclusively for the area the optical data storage reach considerable progress to be able to.

worin die Gruppen R¹, R², R³ entweder

• • ein Wasserstoffatom bedeuten oder
• • R¹ einen beliebigen Alkylrest und R², R³ ein Wasserstoffatom darstellen oder
• • R¹ ein Wasserstoffatom und R², R³ einen unsubstituierten oder
• • substituierten Arylrest bedeuten und Me entweder
• • zwei Wasserstoffatome oder
• • ein Metall bzw. Schwermetall oder
• • ein Halogenmetall oder
• • eine Hydroxy- bzw. Alkoxymetallgruppierung oder
• • eine Oxymetallgruppe

bedeutet.According to the invention, there is provided an optical data storage medium containing organic dyes with different wavelength-selective species and characterized by metal complexes, including metal-free compounds of anthraannulated porphyrazines, having different number transannular endoperoxide bridges in the fused anthracene part, according to formulas I, II, IIIa and IIIb, IV, respectively or V,

wherein the groups R ¹ , R ² , R ^{3 are} either

• • represent a hydrogen atom or
• • R ^{1 is} any alkyl radical and R ² , R ^{3 represent} a hydrogen atom or
• • R ^{1 is} a hydrogen atom and R ² , R ^{3 is} an unsubstituted or
• • substituted aryl radical and Me either
• • two hydrogen atoms or
• • a metal or heavy metal or
• • a metal halide or
• • a hydroxy or Alkoxymetallgruppierung or
• • an oxymetallic group

means.

• • zur Synthese der Spezies eine Photoreaktion durchgeführt wird mit einem Material gemäß Formel V, das als Ausgangsstoff in gelöstem Zustand in Gegenwart von Sauerstoff und eines als Sensibilisator fungierenden Singulettsauerstoffgenerators mit Licht im Bereich der langwelligen Sensibilisatorabsorption bestrahlt wird, bis das Material vollständig in die Spezies gemäß Formel I umgewandelt ist,
• • aus der Lösung gewonnenes Material gemäß Formel I in eine Polymermatrix eingebettet wird,
• • das in die Polymermatrix eingebettete Material gemäß Formel I gezielt und örtlich vorgebbar in Teilbereichen nicht, in anderen Teilbereichen einer stufenweisen Zweiphotonenanregung im Bereich der langwelligen Q-Bande unterworfen wird und dabei die Spezies gemäß Formeln II, IIIa bzw. IIIb, IV sowie gemäß Formel V erzeugt werden.

Finally, the solution according to the invention comprises the information on a method for producing an optical data storage medium containing organic dyes with different wavelength-selective species, and which is characterized in that

• For the synthesis of the species, a photoreaction is carried out with a material according to formula V which is irradiated as starting material in the presence of oxygen and a sensitizing singlet oxygen generator with light in the range of long wavelength sensitizer absorption until the material is completely in the species according to Formula I is converted,
• Embedded material from the solution according to formula I is embedded in a polymer matrix,
• • The material embedded in the polymer matrix material according to formula I targeted and locally specifiable not in sub-areas, in other sub-areas of a stepwise two-photon excitation in the range of long-wave Q band is subjected to the species according to formulas II, IIIa or IIIb, IV and according to formula V are generated.

For the invention in its entirety, that is included in the manufacturing process Characteristic of the synthesis in the presence of a singlet oxygen generator to work, of crucial importance. Surprisingly, it has become shown that thereby the representation of other metal complexes or metal-free compounds of anthraannulated porphyrazines with endoperoxide bridges as the octaphenyltetraanthraporhydrazinato palladium at all succeed. Even in the synthesis of this photo-oxidized palladium complex affects the presence of such a singlet oxygen generator Cheap out. The synthesis progresses hereby another external parameter for the control.

The dyes used differ from the known porphyrazine palladium complex both in the specific R ¹ , R ² and R ³ substituents given, and mainly in a variety of other metal complexes, including metal-free compounds. Their absorption maxima are essentially in the aforementioned range between 850 nm and 650 nm, but there, depending on the respective central Me group and the substituents R ¹ , R ² , R ³ shifted against each other something.

dyes, which are contained in optical data memories, but contain in their preferred forms of presentation also the porphyrazine palladium complex, like this one from its previous application for photodynamic tumor therapy is known.

The Manufacturing process for optical data memories containing the organic dyes, comprises several, each in itself more or less known measures having steps. As mentioned above, comes the step of photochemical synthesis of photochromic species according to formula I - Porphyrazine with four transannular endoperoxide bridges per molecule - its own inventive significance with regard to the presence of a sensitizer acting singlet oxygen generator, because thereby at all first the metal complexes and metal-free compounds in large numbers are representable.

The dyes are insensitive to one-photon excitation in the range of long-wave absorption band and have high thermal stability. The changes which are brought about in stepwise two-photon excitation with short-pulse lasers in the region of the long-wavelength absorption band can be controlled with high accuracy as a function of the irradiation time. In this way, total porphyrazines according to the invention in five different photochromic species are available, ie, the compound without Endoperoxidbrücken - the starting material for the synthesis according to formula V - is in optical data storage memory track on an equal footing with those from monoepidoxy, Diepidioxy-, Triepidioxy- and Tetraepidioxy tetrahydro-tetraanthraporphyrazinen. On the other hand, only the four species with at least one endoperoxide bridge in Be come naturally for function as an oxygen donor costume.

Around To clarify the essence of the invention in more detail, is still first briefly on more general technological background and then on Ways to execute the invention received.

It is known that solutions of the palladium complexes of octabutoxytetranaphthoporphyrazine and octaphenyltetraanthraporphyrazine are photosensitive. Upon excitation of these compounds with an argon ion laser (λ _AN = 514 nm), He-Ne laser (λ _AN = 632 nm) or when exposed to light in the intense Q band, a photochemical reaction is triggered in the presence of oxygen, wherein It is assumed that singlet oxygen is the actually reactive agent (J.Photochem.Photobiol.A: Chemistry 105 (1997) 153). This is formed by energy transfer from the lowest triplet level of the excited palladium porphyrazine to the ground state oxygen present in the reaction solution. Due to the electrophilic properties of singlet oxygen, it can undergo reactions with suitable dienophiles.

in the Case of palladium octabutoxytetranaphtoporphyrazine finds the reaction with the fused naphthalene unit instead, in the case of palladium octaphenyltetraanthraporphyrazine with the fused anthracene rings. Theoretically, this is the addition of four singlet oxygen molecules per molecule of porphyrazine possible. In the case of palladium octabutoxytetranaphtoporphyrazine however only one molecule Singlet oxygen added (J. Am. Chem. Soc. 115 (1993) 8146), while the palladium octaphenyltetraanthraporphyrazine reacts with four singlet oxygen molecules (Tetrahedron Letters 37 (1996) 5083). Here are the corresponding transannular endoperoxides of porphyrazines formed. With the two reactions known from the literature are self-sensitized Photoreactions.

The Photoproduct of palladium octabutoxytetranaphtoporphyrazine is relative unstable and returns to the starting molecule after about 24 hours, while the Tetraepidioxy compound of palladium octaphenyltetraanthraporphyrazine is long-term stable at room temperature.

The Oktaphenyl-tetraepidioxy-octahydro-tetraanthraporphyrazinatopalladium is so far the only described representative of this class. Other Metal complexes of substituted tetraanthtraporphyrrazines, e.g. B. with the central metal atoms nickel, copper, aluminum, oxyvanadium u. a., And the metal-free compounds are compared to light absolutely stable, d. H. a photochemical reaction in the presence of oxygen finds not happening. reasons for that are on the one hand, that the Location of the triplet level of the compound under the activation energy is composed of singlet oxygen, and the z. T. low Triplettmanifoldlebensdauer, the prevents effective energy transfer to the oxygen in the solution.

The technical teaching for carrying out the invention includes that in a photochemical reaction, an oxygen-containing or oxygen-saturated solution of a correspondingly substituted tetraanthraporphyrazine of the general formula V in the presence of a suitable sensitizer capable of producing singlet oxygen with light of wavelength, at which the sensitizer absorbs, is irradiated. In this case, sensitizers which absorb in the range of 400 nm to 800 nm can be used. Suitable, particularly stable sensitizers prove to be metal complexes of tetra-tert-butylporphyrazine (λ _max = 575 nm in benzene) and of tetra-tert-butyl phthalocyanine (λ _max = 661 nm in benzene), preferably with palladium as the central metal atom. These compounds have a high singlet oxygen quantum yield Φ> 0.85. In this case, light in the wavelength range 500 nm to 600 nm or 575 nm to 685 nm can be used.

When Irradiation sources can Laser, halogen or xenon lamps in combination with suitable filters be used. The sensitizer can be useful in amounts by weight up to several times the amount by weight of tetraanthraporphyrazine used V be present. The solution, containing the tetraanthraporphyrrazine V and the sensitizer appropriate before the photoreaction saturated with oxygen and in the course of the reaction continue to fumigate with oxygen. The photoreaction is given priority Room temperature performed. As a solvent come organic solvents, primarily benzene, alkylbenzenes, halogenated benzenes or naphthalenes for use.

The Photoreaction can be followed by absorption spectroscopy. The formed substituted porphyrazines with different numbers Epidioxy groups differ significantly in their absorption behavior and can thus be obtained after different reaction times. The Tetraepidioxy-octahydro-tetraanthrapophyrazine I absorb in dependence of the central metal atom and substituents between 650 nm to 720 nm. Here, the absorption corresponds to that of a corresponding alkyl-substituted phthalocyanine.

The end of the photoreaction can be recognized by the fact that the absorption spectrum no longer changes on further irradiation. The tetraepidioxy-octahydro-tetraanthrapophyrazines I thus shown exhibit an intensive absorption with ε> 10 ⁵ in the red spectrum between 650 nm to 720 nm and have excellent thermal stability up to 150 ° C. The compounds are photostable to single-photon excitation in the range of long-wavelength absorption between 650 nm to 720 nm.

Of the Synthesis step is through five Examples closer explained. The products with different epidioxy groups can be successively produce. The LSI mass spectra of the epidioxy compounds show due to under these conditions (Matrix: 2-Nitrophenyloctylether) occurring ejection of oxygen the molecular ion peaks the compound without epidioxy groups as well as those of the compounds with different numbers of epidioxy groups.

Example 1:

Oktaphenyl-tetraepidioxy-octahydro-tetraanthraporphyrazinato copper

0.8 mg (5 × 10 ^-4 mmol) of octaphenyltetraanthraporphyrazinato copper are dissolved in boiling heat in 20 ml of benzene. After cooling to room temperature, oxygen is introduced into the solution for 20 minutes. After addition of 3 mg (5 × 10 ^-3 mmol) of tetra-tert-butylporphyrazinato-palladium, the solution is stirred and further gassed with oxygen for several hours with a xenon lamp (XBO 300) using a glass filter VG8 (permeable in the range 450 nm to 620 nm) or with an argon ion laser-pumped dye laser [rhodamine 6G, (575 nm)]. The course of the reaction is followed by absorption spectroscopy on the basis of the structure of an absorption band at 680 nm. It is irradiated until absorption spectroscopy can no longer detect bands in the range from 700 nm to 800 nm. The solution is concentrated and thick-layer chromatography on silica gel 60 (Merck) separates the octaphenyl-tetraepidioxy-octahydrotetraanthraporphyrazinato copper from the sensitizer dye. The eluent was a mixture of benzene (60%) / cyclohexane (40%). λ ^max [nm], benzene: 680 (Ig ε: 5.30), 647 (Ig ε4.40), 611 (Ig ε: 4.43)

The 1 shows the absorption spectrum of octaphenyl tetraanthraporphyrazinato copper prior to irradiation (λ ^max = 878 nm) and the photoproduct octaphenyl-tetraepidioxy-octahydro-tetraanthraporphyrazinato copper (λ ^max = 680 nm).

Example 2:

Oktaphenyl-mono-epidioxy-dihydro-tetraanthraporphyrazinato copper

The Method according to example 1 is repeated, but modified so that the photoreaction is stopped becomes, when in the absorption spectrum of the photoproduct, the bands at 849 nm and 815 nm reach their maximum intensity.

Example 3:

Oktaphenyl-diepidioxy-tetrahydro-tetraanthraporphyrazinatum copper

The Method according to example 1 is amended to that the Photoreaktion is stopped when in the absorption spectrum of Photoproduct the band at 778 nm have reached their maximum intensity.

Example 4:

Oktaphenyl-triepidioxy-hexahydro-tetraanthraporphyrazinatum copper

The Method according to example 1 is amended to that the Photoreaktion is stopped when in the absorption spectrum of Photoproduct the band at 713 nm have reached their maximum intensity.

Example 5:

Oktaphenyl-tetraepidioxy-octahydro-tetraanthraporphyrazinatum oxyvanadin

0.8 mg (5 × 10 ⁴ m / mol) of octaphenyl-tetraanthraporphyrazinato oxyvanadine and 3 mg (5 × 10 ^-3 mmol) of tetra-tert-butyl-porphyrazinato palladium are reacted and purified analogously to Example 1.
λ ^max [nm], benzene: 701 (Ig ε: 5.35), 667 sh (Ig ε: 4.81), 629 (Ig ε: 4.83)

Also for two-photon excitation is discussed in the context of the explanations for execution the invention first on a technological background.

The use z. B. of phthalocyanines and naphthalocyanines as recording materials is known ( DE 37 11 762 A1 ; EP 0 279 501 A1 ). In this case, a locally limited state change is triggered by laser light. This is linked to changes in the optical properties of the dyes. So z. B. a change in the absorption maximum, a change in the reflection.

On the other hand, in 3D storage media higher storage densities than the two-dimensional recording by a factor of 1000 should be possible (up to 10 ¹² bits / cm ³ ). The information is written in via simultaneous two-photon absorption and read out via two-photon fluorescence (spiropyran in: Science 245 (1989) 843). The fluorescence intensity is quadratically dependent on the excitation intensity of the laser.

Of the Recording process finds in contrast, with a stepwise two-photon excitation in the red spectral range instead, leading to an irreversible change in the long-wave absorption band the dyes leads. With the complete Decrease in the absorption band is the build up of new absorptions in the linked near IR area. By different irradiation times, z. With an fs laser system, Specific absorption profiles with pronounced maxima in the near IR range are created at different wavelengths. The same absorption profiles can also be achieved by thermal reaction far above 100 ° C (Short pulse thermolysis).

The Application of compounds I-V as optical recording materials takes place either as transparent Substrate, e.g. B. a polymer layer containing the dye, the across from Two-photon excitation with laser light in the red or near IR range is sensitive, or as a recording medium in which between the light absorbing layer and the support a reflective layer located. The polymers used are preferably polycarbonate, polystytol, Polymethyl methacrylate, polystyrene copolymers, polyvinyl chloride and Cellulose ester for use.

Example 6 below serves to explain the writing process of an optical data memory according to the invention. A solution of octaphenyl-tetraepidoxy-octahydro-tetraanthraphorphyrazinato-copper in benzene or a polymethyl methacrylate matrix containing this compound is combined with an fs laser system (pulse duration 100 fs, repetition frequency 1 kHz, photon flux density 9 × 1027 photons / cm ² s) Excitation wavelength irradiated at 680 nm. The changes in the absorption spectrum as a function of time obtained under two-photon excitation are in 2 shown.

In each case, different species are successively formed as intermediates which absorb longer wavelength than the starting compound. Each individual intermediate obtained can then be additionally converted by readjusting the excitation wavelength of the fs laser system into the respective long-wave absorbing secondary products. Overall, the two-photon excitation of four intermediates is thus possible. At longer irradiation times, the band is also reduced at 880 nm (cf. 1 ).

The obtained individual intermediates are long-term stable. The appearance several absorption profiles with pronounced different absorption maxima allowed, the wavelength as an additional "fourth" dimension in the recording material to use. Optical data storage of the type according to the invention allow only a one-time write. Data in tracks or segments of dyes with at least one molecule present there endoperoxide can be stored completely by temperature treatment can not be reconstructed.

Claims (20)

Optical data storage, the organic dyes with different wavelength-selective species containing metal complexes, including metal-free compounds of anthraannulated porphyrazines, which have different number of transannular endoperoxide bridges in the fused anthracene part, according to formulas I, II, IIIa or IIIb, IV or V,

wherein the groups R ₁ , R ₂ , R _{3 are} either • a hydrogen atom or • R _{1 is} any alkyl radical and R ₂ , R _{3 is} a hydrogen atom or • R _{1 is} a hydrogen atom and R ₂ , R _{3 is} an unsubstituted or substituted aryl radical and Me means either • two hydrogen atoms or • a metal or heavy metal or • a halogen metal or • a hydroxy or alkoxy metal grouping or • an oxymetal group. Optical data storage device according to claim 1, characterized by an alkyl-substituted aryl radical for R ₂ , R ₃ and a hydrogen atom for R ₁ . Optical data storage device according to claim 1 or 2, characterized by one of the following species: Cu, Ni, Zn, Sn, Mn, Fe, Pt, Pd, AlCl, GaCl, InCl, AlOH, GaOH, InOH, AlBr, GaBr, InBr, Si (alkyl) ₂ , Si (oalkyl) ₂ , SiCl ₂ , RhCl, RhOH, VO, TiO ₂ as a central Me group. Method for producing an optical data memory according to one the claims 1 to 3, the organic dyes with different wavelength-selective Contains species, thereby marked that • to Synthesis of Species A photoreaction is carried out with a material according to formula V, as the starting material in dissolved Condition in the presence of oxygen and one as a sensitizer acting singlet oxygen generator with light in the area the long-wavelength sensitizer absorption is irradiated until the material Completely into the species according to formula I converted, • out the solution recovered material according to formula I is embedded in a polymer matrix, Embedded in the polymer matrix Material according to formula I targeted and local specifiable in subareas not in other subareas of a stepwise two-photon excitation in the region of the long-wave Q band subjecting the species according to formulas II, IIIa or IIIb, IV and according to formula V are generated. Method according to claim 4, characterized in that that as a singlet oxygen generator, a material having an absorption maximum in the range between 400 nm and 750 nm is used. A method according to claim 5, characterized in that the singlet oxygen generator consists of tetra-tert-butylporphyrazinato palladium with λ ^max = 575 nm. A method according to claim 5, characterized in that the singlet oxygen generator consists of tetra-tert-butylphthalocyaninato-palladium with λ ^max = 661 nm. Method according to one of claims 4 to 7, characterized that for the synthesis of the species one saturated with oxygen organic solvent is used. Process according to claim 8, characterized by benzene as a solvent. Method according to claim 9, characterized by an alkylbenzene as a solvent. A method according to claim 8, characterized by halogenated benzene as solvent. A method according to claim 8, characterized by an alkylated naphthalene as a solvent. A method according to claim 8, characterized by halogenated naphthalene as a solvent. Method according to one of Claims 4 to 13, characterized that the photoreaction is carried out in the temperature range between 50 ° C to -10 ° C. Method according to claim 14, characterized in that that the photoreaction is carried out at room temperature. Method according to one of claims 4 to 15, characterized that the stepwise two-photon excitation with pulsed lasers with ultra-short-time excitation in the red or near IR range as a write operation for the optical Data storage performed becomes. A method according to claim 16, characterized by fs excitation. Method according to claim 16 or 17, characterized that the polymer matrix as a film with embedded dyes of different Species trained and provided with a reflective base becomes. Method according to claim 16 or 17, characterized that the polymer matrix embedded as a layer package with multiple layers Dyes with different species is formed. Method according to claim 19, characterized that in the layer package the individual layers of embedded dyes are formed from materials that are related to the central Me grouping differ from each other.