EP1377968A2

EP1377968A2 - Optical data carrier that contains a heterocyclic azo dye as the light-absorbing compound in the information layer

Info

Publication number: EP1377968A2
Application number: EP02722251A
Authority: EP
Inventors: Horst Berneth; Friedrich-Karl Bruder; Wilfried Haese; Rainer Hagen; Karin HASSENRÜCK; Serguei Kostromine; Peter Landenberger; Rafael Oser; Thomas Sommermann; Josef-Walter Stawitz; Thomas Bieringer
Original assignee: Bayer Chemicals AG
Current assignee: Lanxess Deutschland GmbH
Priority date: 2001-03-28
Filing date: 2002-03-20
Publication date: 2004-01-07
Also published as: WO2002080152A2; AU2002253152A1; WO2002080152A3; JP2004523396A; US20030006516A1; CN1531724A

Abstract

The invention relates to an optical data carrier that contains a preferably transparent substrate that is optionally already coated with one or more reflective layers, onto whose surface an information layer which can be written on with light, optionally one or more reflective layers and optionally a protective layer or a further substrate or a cover layer are applied. Said optical data carrier can be written on and read with blue, red or infrared light, preferably laser light, and the information layer comprises a light-absorbing compound and optionally a binder. The inventive data carrier is further characterized in that at least one heterocyclic azo dye is used as the light-absorbing compound.

Description

Optical data carrier containing a heterocyclic azo dye in the information layer as a light-absorbing compound

The invention relates to a write-once optical data carrier, which in the

Information layer contains a heterocyclic azo dye as a light-absorbing compound, and a method for their preparation.

The write-once optical data carriers using special light-absorbing substances or their mixtures are particularly suitable for use with high-density writable optical data storage devices that work with blue laser diodes, in particular GaN or SHG laser diodes (360 - 460 nm) and / or for use with DVD-R or CD-R discs that work with red (635 - 660 nm) or infrared (780 - 830 nm) laser diodes, as well as the application of the above-mentioned dyes to a polymer substrate, in particular polycarbonate

Spin coating or vapor deposition.

The compact disk (CD-R, 780 nm), which can be written on once, has experienced enormous volume growth recently and represents the technically established system.

The next generation of optical data storage media - the DVD - is currently being launched on the market. The storage density can be increased by using shorter-wave laser radiation (635 to 660 nm) and a higher numerical aperture NA. The recordable format in this case is the DVD-R.

Today optical data storage formats using blue laser diodes (based on GaN, JP 08191171 or Second Harmonie Generation SHG JP 09050629) (360 nm to 460 nm) with high laser power are being developed. Writable optical data storage devices will therefore also be used in this generation. The storage density that can be achieved depends on the focus of the laser spot in the information level. The spot size scales with the laser wavelength λ / NA. N / A is the numerical aperture of the objective lens used. To obtain the highest possible storage density, the aim should be to use a wavelength λ that is as short as possible. 390 nm are currently possible on the basis of semiconductor laser diodes.

The patent literature describes dye-based writable optical data memories which are equally suitable for CD-R and DVD-R systems (JP-A 11 043 481 and JP-A 10 181 206). For a high reflectivity and a high modulation level of the readout signal, as well as for a sufficient sensitivity when writing, use is made of the fact that the IR wavelength 780 nm of the CD-R lies at the foot of the long-wave flank of the absorption peak of the dye. the red wavelength 635 nm or 650 nm of the DVD-R lies at the foot of the short-wave flank of the absorption peak of the dye. This concept is described in JP-A 02 557 335, JP-A 10 058 828, JP-A 06 336 086, JP-A 02 865 955, WO-A 09 917 284 and US-A 5 266 699 to the 450 nm range Working wavelength extended on the short-wave flank and the red and IR range on the long-wave flank of the absorption peak.

In addition to the optical properties mentioned above, the writable h formation layer made of light-absorbing organic substances must have a morphology which is as amorphous as possible in order to keep the noise signal as small as possible when writing or reading. For this purpose, it is particularly preferred that when the substances are applied by spin coating from a solution, by vapor deposition and / or sublimation, subsequent crystallization of the light-absorbing substances with metallic or dielectric layers in vacuum is prevented.

The amorphous layer of light-absorbing substances should preferably have a high heat resistance, since otherwise further layers of organic or inorganic material, which are applied to the light-absorbing information layer by sputtering or vapor deposition, are diffused by diffusion

Form interfaces and thus adversely affect reflectivity. About that In addition, a light-absorbing substance with too low heat resistance at the interface to a polymer carrier can diffuse into it and in turn adversely affect the reflectivity.

An excessively high vapor pressure of a light-absorbing substance can sublimate the above-mentioned sputtering or vapor deposition of further layers in a high vacuum and thus reduce the desired layer thickness. This in turn leads to a negative influence on the reflectivity.

The object of the invention is therefore to provide suitable compounds which meet the high requirements (such as light stability, favorable signal-to-noise ratio, damage-free application to the substrate material, etc.) for use in the information layer in a write-once optical data carrier, in particular for high-density recordable optical media Meet data storage formats in a laser wavelength range from 340 to 680 nm.

It has surprisingly been found that light-absorbing compounds from the group of heterocyclic azo dyes can meet the above-mentioned requirement profile particularly well.

The invention therefore relates to an optical data carrier, comprising a preferably transparent substrate, optionally already coated with one or more reflection layers, on the surface of which an information layer which can be written on with light, optionally one or more reflection layers and optionally a protective layer or a further substrate or a covering layer are applied, which can be written and read with blue or red light, preferably laser light, the information layer containing a light-absorbing compound and optionally a binder, characterized in that at least one heterocyclic azo dye is used as the light-absorbing compound. The highly absorbent compound should preferably be thermally changeable. The thermal change preferably takes place at a temperature <600 ° C., particularly preferably at a temperature <400 ° C., very particularly preferably at a temperature <300 ° C., in particular <200 ° C. Such a change can be, for example, a decomposition or chemical change in the chromophoric center of the light-absorbing compound.

A heterocyclic azo dye of the formula is preferred

wherein

K for the rest of a coupling component of the formula

(III) stands

X ^{1 represents} N or CH, X ^{2 represents} O, S, NR ⁹ or CH, but X ¹ and X ² do not simultaneously represent CH,

A together with X ¹ and X ² and the carbon atom bonded between them represents a five- or six-membered aromatic or quasi-aromatic heterocyclic ring which contains 1 to 4 heteroatoms and / or benzylated or naphthanellated and / or substituted by nonionic radicals can be,

X r3 ^{J stands} for O or S,

X ^{4 represents} CR ¹⁰ or N,

R ¹ , R ² , R ⁶ , R ⁷ and R ⁹ independently of one another are hydrogen, Ci to C ₆ alkyl, C ₅ to C ₇ cycloalkyl, C ₆ to C ₁₀ aryl or C to C ₁₅ Aralkyl or

NR R ² and NR ⁶ R ⁷ independently of one another represent pyrrolidino, morpholino, piperazino or piperidino,

R ³ and R ⁵ independently of one another represent hydrogen, CT to C ₆ alkyl, Ci to C ₆ alkoxy or halogen or

R ³ ; R ² and R ⁵ ; R independently of one another form a two- or three-membered bridge which contains O or N and can be substituted by nonionic radicals,

R ⁴ for hydrogen, C_ to C ₆ alkyl, Ci to C ₆ alkoxy, halogen, C to C ₆

Acylamino, Ci to C ₆ alkylsulfonylamino, C ₆ to Cio arylcarbonylamino or C ₆ to C ₁₀ arylsulfonylamino,

R ^{8 represents} hydrogen, Ci to C ₆ alkyl, halogen, C ₆ to C ₁₀ aryl, bis Ci to C ₆ dialkylamino, pyrrolidino, piperidino or morpholino and R ^{10 represents} hydrogen, cyano, Ci to C ₆ alkyl, halogen or C ₆ to C ₁₀ aryl,

equivalent.

. As non-ionic radicals, for example, Ci to C ₄ come - alkyl, Ci to C ₄ alkoxy, halogen, cyano, nitro, Ci to C ₄ alkoxycarbonyl, C _\ - to C ₄ alkylthio, Ci to C ₄ - Alkanoylamino, Benzoylamino, mono- or di-Ci to C ₄ alkylamino in question.

Alkyl, alkoxy, aryl and heterocyclic radicals can optionally carry further radicals such as alkyl, halogen, nitro, cyano, CO-NH ₂ , alkoxy, trialkylsilyl, trialkylsiloxy or phenyl, the alkyl and alkoxy radicals can be straight-chain or branched , The alkyl radicals can be partially or pearlized, the alkyl and alkoxy radicals can be ethoxylated or propoxylated or silylated, neighboring

Alkyl and / or alkoxy radicals on aryl or heterocyclic radicals can together form a three- or four-membered bridge and the heterocyclic radicals can be fused to benzine and / or quaternized.

Alkyl radicals, in particular those with the meaning R ¹ , R ² , R ⁶ and R ⁷ , can also carry ionic radicals such as ammonium or COO ^" or SO ₃ ^" groups. Examples of such alkyl radicals are -CH ₂ -CH ₂ -N (CH ₃ ) ₃ ⁺ An or -CH ₂ - SO ₃ ^" M ⁺ , where An ^{" stands} for an anion, for example tetrafluoroborate, and M ^{+ stands} for a cation, eg tetramethylammonium.

The rest of the formula is particularly preferred

for benzthiazol-2-yl, benzoxazol-2-yl, benzimidazol-2-yl, thiazol-2-yl, isothiazol-3-yl, isoxazol-3-yl, imidazol-2-yl, pyrazol-5-yl, l , 3,4-thiadiazol-2-yl, l, 2,4-thiadiazol-5-yl, l, 2,3-thiadiazol-5-yl, l, 3,4-oxadiazol-2-yl, 1,3 , 4-triazol-2-yl, thiophene-2-yl, benzothiophene-2-yl, 2- or 4-pyridyl, 2- or 4-quinolyl, these radicals each having Ci to C ₆ alkyl, Ci - up to C ₆ -

Alkoxy, fluorine, chlorine, bromine, iodine, cyano, nitro, Ci- to C _ö alkoxycarbonyl, Ci to C ₆ alkylthio, Ci- to C ₆ acylamino, C ₆ - to C ₁₀ -aryl, C ₆ - to Cio-aryloxy, C ₆ - to Cio-arylcarbonylamino, mono- or di-Ci- to C ₆ -alkylamino, N-Ci- to C ₆ -alkyl-NC ₆ - to Cio-arylamino, pyrrolidino, pipidino, Morpholino or piperazino can be substituted.

In a very particularly preferred form, the heterocyclic azo dyes used are those of the formula

wherein

X ⁵ and X ⁶ independently of one another represent CR ¹² or N,

R ^{11 is} hydrogen, Ci to C ₄ alkyl, Ci to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy,

C ₆ - to Ci _ö -aryloxy, Ci- to C ₄ -alkylthio, mono- or bis-Ci- to C ₄ -alkylamino, N-Ci- to C ₄ -alkyl-NC ₆ - to C ₁₀ -arylamino, N -Ci to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci- to C ₄ -alkyl-NC ₇ - to C ₁₂ -aralkylamino, Ci- to C ₄ -alkanoylamino, C ₆ - until Cio-aroylamino, pyrrolidino, piperidino, piperazino or morpholino is present, R ^{12 represents} hydrogen, Ci to C alkyl, Ci to C ₄ alkoxy, cyano, Ci to C ₄ alkoxycarbonyl or C ₆ to Cio aryl, or if X ^{6 represents} CR ¹² ,

R ^π ; R ¹² together form a -CH = CH-CH = CH bridge,

NR * R ² for mono- or bis-d- to C -alkylamino, NC to C ₄ -all yl-NC ₆ - to C _10- -arylamino, N-Ci- to C -alkyl-NC ₅ - to C _δ -cycloalkylamino, N-Ci to C ₄ - alkyl-NC ₇ to C ₁ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Ci to C ₄ alkyl or Ci to C ₄ alkoxy or

R ³ ; R ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or -CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ Bridge stand,

R ^{5 represents} hydrogen or

R ⁵ ; R ² together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or -CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ Bridge stand and

R ⁴ for hydrogen, Ci to C ₄ alkyl, C to C ₄ alkoxy, chlorine, Ci to C ₄ alkanoylamino, N-Ci to C ₄ alkyl-N-Cτ to C ₄ - Alkanoylamino, Ci- to C - alkylsulfonylamino, N-Ci- to C -alkyl-N-Cι- to C ₄ -alkylsulfonylamino, C ₆ - to Cio-aroylamino or C ₆ - to C ₁₀ arylsulfonylamino.

In a likewise very particularly preferred form, the heterocyclic azo dyes used are those of the formula wherein

X ^{3 represents} CR 1 ⁱ 2 or N,

R ^{11 is} hydrogen, Ci to C alkyl, Ci to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio aryloxy, Ci to C alkylthio, mono- or bis-Cr to C - alkylamino, N-Ci to C -alkyl-NC ₆ - to C ₁₀ -arylamino, N-Ci- to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci- to C ₄ - Alkyl-NC ₇ - to C ₁₂ -aralkylamino, Ci- to C ₄ -alkanoylamino, C ₆ - to C ₁₀ -arroylamino, pyrrolidino,

Piperidino, Piperazino or Morpholino stands,

R, 12 represents hydrogen, Ci to C alkyl, Ci to C alkoxy, cyano, nitro, Ci to C ₄ alkoxycarbonyl or C ₆ to Cio aryl, or if X represents CR,

R> l ^U l; .τR »1 ¹ 2 ^Z together form a -CH = CH-CH = CH bridge,

NR R ² for mono- or bis-Cr to C ₄ -alkylamino, N-Ci to C ₄ -alkyl-NC ₆ - to C _10- -arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - bis C ₆ -cycloalkylamino, N-Ci to C ₄ - alkyl-NC - to Ci ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or

Morpholino stands

R ^{3 represents} hydrogen, Ci to C ₄ alkyl or Ci to C ₄ alkoxy or

R ³ ; R ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or

-CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge, R ^{5 represents} hydrogen or

R ⁵ ; R ² together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH2-, -O-CH ₂ -CH ₂ - or -CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ - Stand bridge and

R ^{4 is} hydrogen, Ci to C alkyl, Ci to C ₄ alkoxy, chlorine, Ci to C ₄ alkanoylamino, N-Ci to C alkyl-N-Ci to C ₄ alkanoylamino , Ci to C ₄ - alkylsulfonylamino, N-Ci to C ₄ alkyl-N-Ci to C ₄ alkylsulfonylamino, C ₆ - to C ₁₀ -Aroylamino or C ₆ - to C ₁₀ is -Arylsulfonylamino.

In a likewise very particularly preferred form, the heterocyclic azo dyes used are those of the formula

wherein

X and X independently of one another represent C-R 12 or N,

R ^{11 is} hydrogen, Ci to C ₄ alkyl, Ci to C alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Ci _ö aryloxy, Ci to C ₄ alkylthio, mono- or bis -Ci- to C ₄ -

Alkylamino, N-Ci to C-alkyl-NC ₆ - to Cio-arylamino, N-Ci- to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ -alkyl-NC ₇ to C ₁₂ aral l ylamino, C to C alkanoylamino, C ₆ to Cio aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{12 represents} hydrogen, Ci to C ₄ alkyl, Ci to C alkoxy, cyano, Ci to C alkoxycarbonyl or C ₆ to C ₁₀ aryl or if X ^{6 represents} CR ¹² , R ^U ; R ¹² together form a -CH = CH-CH = CH bridge,

R ^{13 represents} hydrogen, Ci to C alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ₁₂ aralkyl or C ₆ to Cio aryl,

NR ^J R ² for mono- or bis-Ci- to C ₄ -alkylamino, NC to C ₄ -alkyl-NC ₆ - to C _10- -arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ -alkyl-NC- to Ci ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Ci to C ₄ alkyl or Ci to C ₄ alkoxy or

R ^{5 represents} hydrogen or

R ^{4 is} hydrogen, Ci to C ₄ alkyl, Ci to C ₄ alkoxy, chlorine, Ci to C ₄ alkanoylamino, N-Ci to C ₄ alkyl-N-Ci to C ₄ alkanoylamino, Ci to C ₄ - alkylsulfonylamino, N-Ci to C ₄ alkyl-N-Ci to C ₄ alkylsulfonylamino, C ₆ - to Cio-aroylamino or C ₆ - to C ₁₀ is -Arylsulfonylamino.

R ¹¹ for hydrogen, C to C alkyl, Cr to C alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio aryloxy, Cr to C alkylthio, mono- or bis-Cr to C ₄ Alkylamino, N-Ci to C ₄ alkyl-NC ₆ - to Cio-arylamino, N-Cr to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Cr to C-alkyl-NC ₇ - bis C ₁₂ aral kylamino, Ci to C ₄ alkanoylamino, C ₆ to Cio aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{13 represents} hydrogen, C to C ₄ alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ^ aralkyl or C ₆ to C ₁₀ aryl,

NR R ² for mono- or bis-Cr to C ₄ -alkylamino, N-Ci to C -alkyl-NC ₆ - to C _10- -arylamino, N-Cr to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C -

Alkyl-NC ₇ - to Cn-aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R represents hydrogen, Ci to C - alkyl or Cr to C ₄ - alkoxy or

R ^{5 represents} hydrogen or R ⁵ ; R ² together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or -CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ -Bmcke stand and

R ⁴ for hydrogen, d- to C ₄ -alkyl, Cr to C -alkoxy, chlorine, d- to C -alkanoylamino, N-Ci to C -alkyl-N-Cr to C ₄ -alkanoylamino, Ci- to C ₄ - alkylsulfonylamino, N-Cr to C ₄ -alkyl-N-Cr to C ₄ -alkylsulfonylamino, C ₆ - to Cio-aroylamino or C ₆ - to do-arylsulfonylamino.

wherein

X ⁵ and X ⁶ independently of one another represent CR 12 or N,

R n for hydrogen, d- to C -alkyl, d- to C -alkoxy, C ₅ - to d-cycloaikoxy, C ₆ - to do-aryloxy, Cr to C ₄ -alkylthio, mono- or bis-Ci- bis C - alkylamino, N-Ci to C ₄ alkyl-NC ₆ - to Cio-arylamino, N-Cr to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Cr to C-alkyl-NC ₇ - to C ₁₂ -aralkylamino, Ci- to C ₄ -alkanoylamino, C ₆ - to do-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ¹² for hydrogen, Cr to C ₄ alkyl, d to C ₄ alkoxy, cyano, Ci to C -

Alkoxycarbonyl or C ₆ - to C ₁₀ aryl or when X stands for CR 12.

R ^π ; R together form a -CH = CH-CH = CH bridge, X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR) 6 ° Rτ> 7 ⁷ . for mono- or bis-d- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to C _10- -arylamino, N-Cr to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ -alkyl-NC to C ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, C 1 -C ₄ -alkyl, chlorine, C ₆ -C ₁₀ -alkyl, bis-C 1 -C ₄ -dialkylamino, pyrrolidino, piperidino or morpholino.

wherein

X ^{5 represents} CR .1 ⁱ 2 or N,

R ^{11 is} hydrogen, Ci to C alkyl, Ci to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to do aryloxy, Cr to C ₄ alkylthio, mono- or bis-Ci - to C - alkylamino, N-Cr to C ₄ -alkyl-NC ₆ - to Cio-arylamino, N-Cr to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci- to C ₄ -alkyl -NC ₇ - to C ₁₂ -aralkylamino, Ci- to C ₄ -alkanoylamino, C ₆ - to do-aroylamino, pyrrolidino, piperidino, piperazino or morpholino, R ^{12 represents} hydrogen, Ci to C ₄ alkyl, Ci to C alkoxy, cyano, nitro, Cr to C alkoxycarbonyl or C ₆ to Cio aryl, or if X represents CR,

R ¹¹ ; R ¹² together form a -CH = CH-CH = CH bridge,

X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-d- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to C _10- -arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - bis C ₆ -cycloalkylamino, N-Ci to C ₄ -alkyl-NC- to Ci ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, Ci to C ₄ alkyl, chlorine, C ₆ to Cio aryl, bis-d to C ₄ dialalllamino, pyrrolidino, piperidino or morpholino.

wherein

X ⁵ and X ⁶ independently of one another represent CR ¹² or N, R ^u for hydrogen, d- to C ₄ -alkyl, Ci- to C ₄ -alkoxy, C ₅ - to C ₆ -cycloalkoxy, C ₆ - to Cio-aryloxy, d- to C ₄ -alkylthio, mono- or bis -Cr to C ₄ - all ylamino, N-Ci to C ₄ -alkyl-NC ₆ - to Cio-arylamino, Nd- to C ₄ - alkyl-NC ₅ - to C ₆ -cycloalkylamino, NC _! - to C ₄ -alkyl-NC ₇ - to -C ₂ -aral- kylamino, Ci- to C -alkanoylamino, C ₆ - to Cio-aroylamino, pyrrolidino,

Piperidino, Piperazino or Morpholino stands,

R ^{12 is} hydrogen, Cr to C alkyl, Ci to C alkoxy, cyano, d to C ₄ alkoxycarbonyl or C ₆ to C ₁₀ aryl, or when X ^{6 is} CR ¹² or when X ⁵ stands for CR ¹² ,

R ^π ; R ¹² together form a -CH = CH-CH = CH bridge,

R ^{13 represents} hydrogen, d- to C ₄ -alkyl, C ₅ - to C ₆ -cycloalkyl, C ₇ - to -CC ₂ aralkyl or C ₆ - to C ₁₀ -aryl,

X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-d to C ₄ alkylamino, Nd to C ₄ alkyl NC ₆ to Cι ₀ . -arylamino, Nd- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci- to C ₄ - alkyl-NC ₇ - to Ci2-aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, Ci to C ₄ alkyl, chlorine, C ₆ to Cio-aryl, bis-Cr to C ₄ dialkylamino, pyrrolidino, piperidino or morpholino.

R ^{11 is} hydrogen, Cr to C alkyl, Ci to C alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio aryloxy, Ci to C alkylthio, mono- or bis-Cr to C ₄ - alkylamino, N-Ci to C ₄ alkyl-NC ₆ - to Cio-arylamino, N-Cr to C - alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ alkyl-NC ₇ - to C ₁₂ -arykylamino, Cr to C ₄ -alkanoylamino, C ₆ - to do-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{13 represents} hydrogen, C to C ₄ alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ₁₂ aralkyl or C ₆ to C ₁₀ aryl,

X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-Cr to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to C _10- -arylamino, N-Cr to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Cr to C ₄ - alkyl-NC - to Ci ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or

Morpholino stands

R ^{8 represents} hydrogen, d- to C ₄ -alkyl, chlorine, C ₆ - to C ₁₀ -aryl, bis-Ci to C ₄ -dialkylamino, pyrrolidino, piperidino or morpholino. For a once writable optical data carrier according to the invention, which is written and read with the light of a blue laser, preference is given to heterocyclic azo dyes whose absorption maximum λ _{ma 2 is} in the range 420 to 550 nm, the wavelength λι _{/ 2} at which the extinction in the short-wave flank of the absorption maximum of wavelength λ _maX2 half of the

Extinction _value at λ _max2 , and the wavelength λι _{/ 10} , at which the extinction in the short-wave flank of the absorption maximum of the wavelength λ _{maX2 is} one tenth of the extinction _value at λ _maX2 , preferably not more than 80 nm apart. Such a heterocyclic azo dye preferably has no shorter-wave maximum λ _max ι up to a wavelength of 350 nm, particularly preferably up to 320 nm, very particularly preferably up to 290 nm.

Preferred are heterocyclic azo dyes with an absorption maximum λ _max2 of 430 to 550 nm, in particular 440 to 530 nm, very particularly preferably 450 to 520 nm.

The heterocyclic azo dyes λi _{/ 2} and λ io, as defined above, are preferably not more than 70 nm apart, more preferably not more than 50 nm apart, very particularly preferably not more than 40 nm apart.

For a write-once optical data carrier _{according to the invention} which is written and read with the light of a red laser, preference is given to heterocyclic azo dyes whose absorption maximum λ _{maX2 is} in the range from 500 to 650 nm, the wavelength λi _{/ 2} at which the absorbance in the long-waved flank of the absorption maximum of the wavelength λ _maX2 half of the

Extinction value at λ _{ma is 2} , and the wavelength λi _{/ 10} , at which the extinction in the long-wave flank of the absorption maximum of the wavelength λ _{maX2 is} one tenth of the extinction _value at λ _maX2, is preferably no more than 60 nm apart. Such a heterocyclic azo dye preferably up to a wavelength of 750 nm, particularly preferably 800 nm, very particularly preferably 850 nm, no longer-wave maximum λ _ma χ3.

Heterocyclic azo dyes with an absorption maximum λ _maX 2 of 510 to 620 nm are preferred.

Heterocyclic azo dyes with an absorption maximum λ _ma χ ₂ of 530 to 610 nm are particularly preferred.

Heterocyclic azo dyes with an absorption maximum λ _maX2 of 550 to 600 nm are very particularly preferred.

These heterocyclic azo dyes λi ₂ and λi _{/ 10} , as defined above, are preferably not more than 50 nm apart, more preferably not more than 40 nm apart, very particularly preferably not more than 30 nm apart.

At the absorption maximum λ _maX 2, the heterocyclic azo dyes preferably have a molar extinction coefficient ε> 25000 1 / mol cm, preferably> 35000 1 / mol cm, particularly preferably> 40,000 1 / mol cm, very particularly preferably> 50,000 1 / mol cm.

The absorption spectra are measured, for example, in solution.

Suitable heterocyclic azo dyes with the required spectral properties are, in particular, those in which the dipole moment change Δμ = | μ _g - μ _ag |, ie the positive difference between the dipole moments in the ground state and the first excited state, is as small as possible, preferably <5 D, particularly preferred <2 D. A method for determining such a dipole moment change Δμ is described, for example, in F. Würthner et al, Angew. Chem. 1997, 109, 2933 and in the literature cited therein. Low solvatochromism (dioxane / DMF) is also suitable Selection criterion. Preference is given to heterocyclic azo dyes whose solvatochromism Δλ = | λoMF - λoioxanl, ie the positive difference in the absorption wavelengths in the solvents dimethylformamide and dioxane, <20 nm, particularly preferably <10 nm, very particularly preferably <5 nm.

Heterocyclic azo dyes which are particularly suitable for the purposes of the invention are those of the formula

wherein

X ⁵ and X ⁶ stand for N,

R n for hydrogen, methyl, ethyl, propyl, butyl, methoxy, ethoxy, phenoxy, methylthio, ethylthio, propylthio, butylthio, dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino , N-methyl-N-hydroxyethylamino, bis- (cyanoethyl) amino, bis- (methoxyethyl) amino, bis- (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, Methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

NR, lr R> 2 for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis- (cyanoethyl) amino, bis- (methoxyethyl ) amino, bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenyl- amino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino,

R represents hydrogen, methyl or methoxy or

R> 3 ^years ; R _D ι ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or -CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge stand,

R represents hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino, acetylamino, trifluoroacetylamino, propionylamino, butanoylamino, N-methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methane amino or benzenesulfonylamino,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

Heterocyclic azo dyes which are very particularly suitable in the sense of the invention are those of the formula

wherein

X ^{5 stands} for CR 1 ¹ 2 ^Z ,

X ° stands for CR 1 ^l 2 ' R ^u and R ¹² independently of one another represent hydrogen, methyl, ethyl, cyano, chlorine, nitro, methoxycarbonyl or ethoxycarbonyl,

R ^{12 'represents} hydrogen, methyl or ethyl,

NO ^! R ² for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis- (cyanethyl) amino, bis- (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenyl-a ino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl - or N-cyanoethylpiperazino or morpholino,

R ^{3 represents} hydrogen, methyl or methoxy or

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino,

Acetylamino, trifluoroacetylamino, propionylamino, butanoylamino, N-methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methanesulfonylamino, benzoylamino or benzenesulfonylamino

where the alkyl radicals such as propyl, butyl, etc. can be branched.

Heterocyclic azo dyes which are very particularly suitable in the sense of the invention are those of the formula wherein

X ^{5 represents} N,

X ^{6 stands} for CR ¹² ,

R ¹¹ for hydrogen, methyl, ethyl, propyl, butyl, methoxy, ethoxy, phenoxy, methylthio, ethylthio, propylthio, butylthio, dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino , N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino, bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, Methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

R ^{12 represents} hydrogen, methyl or ethyl or

R ^π ; R ¹² together represent a -CH = CH-CH = CH bridge, which can be substituted by methyl, chlorine, nitro or methoxy,

R ^ R ² for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N Cyanoethylpiperazino or morpholino, R ^{3 represents} hydrogen, methyl or methoxy or

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino, acetylamino, trifluoroacetylamino, propionylamino, butanoylamino, N-

Methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methanesulfonylamino, benzoylamino or benzenesulfonylamino,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X ^{3 represents} N,

R ^{n represents} hydrogen, methyl, ethyl or phenyl, NO ^! R ² for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis- (cyanethyl) amino, bis- (methoxyethyl) amino, bis - (Hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N Cyanoethylpiperazino or morpholino,

R represents hydrogen, methyl or methoxy or

R ³ ; R ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH2-CH ₂ -, -O-CH ₂ -CH ₂ - or

-CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge,

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino,

Acetylamino, trifluoroacetylamino, propionylamino, butanoylamino, N-methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methanesulfonylamino, benzoyl-a ino or benzenesulfonylamino

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein X ^{5 stands} for CR ¹² ,

R ^{11 represents} hydrogen, methyl, ethyl or phenyl,

R ^{12 represents} hydrogen, cyano, nitro, methoxycarbonyl or ethoxycarbonyl or

R ^π ; R ¹² together represent a -CH = CH-CH = CH bridge, which can be substituted by methyl, methoxy, chlorine, cyano, nitro, methoxycarbonyl or ethoxycarbonyl,

NO ^! R ² for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis- (cyanoethyl) amino, bis- (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino,

R ^{3 represents} hydrogen, methyl or methoxy or

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino,

Acetylamino, trifluoroacetylamino, propionylamino, butanoylamino, N-

Methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methanesulfonylamino, benzoylamino or benzenesulfonylamino, where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X ^{5 represents} N,

X ^{6 stands} for CR ¹² ,

R ¹¹ for hydrogen, methyl, ethyl, methoxy, ethoxy, methylthio, amino, dimetliylamino, diethylamino, formylamino, acetylamino, benzoylamino,

Pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

R ^{12 represents} hydrogen, methyl, ethyl, cyano, methoxycarbonyl, ethoxycarbonyl or phenyl,

R ^{13 represents} hydrogen, methyl, ethyl, propyl, butyl, cyclohexyl, benzyl or phenyl,

NR R ² for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl

N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino, bis (hydroxy) ethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino stands,

R ^{3 represents} hydrogen, methyl or methoxy or

-CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge,

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, formylamino,

Acetylamino, trifluoroacetylamino, propionylamino, butanoylamino,

N-methyl-N-acetylamino, methanesulfonylamino, ethanesulfonylamino, trifluoromethanesulfonylamino, N-methyl-N-methanesulfonylamino, benzoylamino or benzenesulfonylamino,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein R ^{11 represents} hydrogen, methyl, ethyl, methoxy, phenyl, amino, dimethylamino, acetylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

NR R for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylethylamino, bis- (cyanoethyl) amino, bis- (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino,

R ^{3 represents} hydrogen, methyl or methoxy or

R ^{5 represents} hydrogen and

R ⁴ for hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, fonnylamino,

Acetylamino, trifluoroacetylamino, propionylamino, butanoylamino,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

X ^{5 and} X ⁶ stand for N,

R 11 for hydrogen, methyl, ethyl, propyl, butyl, methoxy, ethoxy, phenoxy, methylthio, ethylthio, propylthio, butylthio, dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino , N-methyl-N-hydroxyethylamino, bis- (cyanoethyl) amino, bis- (methoxyethyl) amino, bis- (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, Methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

NR ⁶ R ⁷ for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl

N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino, bis (hydroxyethyl) amino, N-methyl-N-benzylamino , N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino, and

R ^{8 represents} hydrogen, methyl, ethyl, chlorine or phenyl, where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X ^{3 stands} for CR 1 ¹ 2 ^Z ,

X ° stands for CR 1 ⁱ 2 ^Z ',

R ^π and R ¹² independently of one another represent hydrogen, methyl, ethyl, cyano, chlorine, nitro, methoxycarbonyl or ethoxycarbonyl,

R .12 represents hydrogen, methyl or ethyl,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

NR ⁶ R ⁷ for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenyl- amino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino, and

R ^{8 represents} hydrogen, methyl, ethyl, chlorine or phenyl,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X ^{3 represents} N,

X ^{6 stands} for CR ¹² ,

R ^{12 represents} hydrogen, methyl or ethyl or R ^π ; R ¹² together represent a -CH = CH-CH = CH bridge, which can be substituted by methyl, chlorine, nitro or methoxy,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

NR ⁶ R ⁷ for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino , Bis (hydroxyethyl) amino, N-methyl-N-benzylamino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl, N-hydroxyethyl or N-cyanoethylpiperazino or morpholino, and

R ^{8 represents} hydrogen, methyl, ethyl, chlorine or phenyl,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X ^{3 represents} N, R ^{11 represents} hydrogen, methyl, ethyl or phenyl,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

R represents hydrogen, methyl, ethyl, chlorine or phenyl,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein

X rS ³ _Ä stands for C -.- τR) 1 ⁱ 2 ^Z ,

R ^{11 represents} hydrogen, methyl, ethyl or phenyl, R ^{12 represents} hydrogen, cyano, nitro, methoxycarbonyl or ethoxycarbonyl or

R ⁿ ; R ¹² together represent a -CH = CH-CH = CH bridge, which can be substituted by methyl, methoxy, chlorine, cyano, nitro, methoxycarbonyl or ethoxycarbonyl,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

R ^{8 represents} hydrogen, methyl, ethyl, chlorine or phenyl,

where the alkyl radicals such as propyl, butyl, etc. can be branched.

wherein X ^{5 represents} N,

X ^{6 stands} for CR ¹² ,

R ¹¹ for hydrogen, methyl, ethyl, methoxy, ethoxy, methylthio, amino, dimethylamino, diethylamino, formylamino, acetylamino, benzoylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or Morpholino stands

R represents hydrogen, methyl, ethyl, propyl, butyl, cyclohexyl, benzyl or phenyl,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl) amino, bis (hydroxyethyl) amino, N-methyl-N-benzylamino , N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl, N-ethyl,

N-hydroxyethyl or N-cyanoethyl piperazino or morpholino, and

R ^{8 represents} hydrogen, methyl, ethyl, chlorine or phenyl,

where the alkyl radicals such as propyl, butyl, etc. can be branched. Heterocyclic azo dyes which are very particularly suitable in the sense of the invention are those of the formula

wherein

R ^{11 represents} hydrogen, methyl, ethyl, methoxy, phenyl, amino, dimethylamino, acetylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N-hydroxyethyl- or N-cyanoethylpiperazino or morpholino,

X ^{3 represents} O or S,

X ^{4 represents} N or CH,

NR ⁶ R ⁷ for dimethylamino, diethylamino, dipropylamino, dibutylamino, N-methyl-N-cyanoethylamino, N-methyl-N-methoxyethylamino, N-methyl-N-hydroxyethylamino, bis (cyanoethyl) amino, bis (methoxyethyl ) amino, bis (hydroxyethyl) amino, N-methyl-N-benzylarnino, N-methyl-N-phenylamino, phenylamino, methoxyphenylamino, pyrrolidino, piperidino, N-methyl-, N-ethyl-, N- Hydroxyethyl- or N-cyanoethylpiperazino or morpholino, and

Heterocyclic azo dyes are known in some cases, e.g. B. from DE-OS 2 811 258, FR 2 394 587, DE-OS 4 343 454, EP-A 0 702 107, DE-OS 3 611 228, Am. Dyest. Rep. 1988, 77, 32.

The invention further relates to heterocyclic azo dyes of the formulas (X), (XI) or (XII), where the radicals X ³ to X ⁶ , R ⁶ to R ⁸ , R ¹¹ to R ¹³ are the general, particularly preferred and have particularly preferred meaning.

The light-absorbing substances described guarantee a sufficiently high reflectivity (> 10%) of the optical data carrier in the blank state as well as a sufficiently high absorption for the thermal degradation of the information layer in the case of selective illumination with focused light if the light wavelength is in the range from 360 to 460 nm and 600 to 680 nm. The contrast between the written and unwritten areas on the data carrier is realized by the change in reflectivity of the amplitude and the phase of the incident light by the optical properties of the information layer which have changed after thermal degradation.

The heterocyclic azo dyes are preferably applied to the optical data carrier by spin coating or vacuum evaporation. The heterocyclic azo dyes can be mixed with one another or with other dyes with identical spectral properties. In addition to the heterocyclic azo dyes, the information layer can contain additives such as binders, wetting agents, stabilizers, thinners and sensitizers and other constituents.

The optical data storage device can carry additional layers such as metal layers, dielectric layers and protective layers in addition to the irrformation layer. metals and dielectric layers serve, among other things, to adjust the reflectivity and the heat balance. Depending on the laser wavelength, metals can be gold, silver, aluminum and others. Dielectric layers are, for example, silicon dioxide and silicon nitride. Protective layers are, for example, photocurable lacquers, (pressure-sensitive) adhesive layers and protective films.

Preferred pressure-sensitive adhesive layers consist mainly of acrylic adhesives. Nitto Denko DA-8320 or DA-8310, disclosed in patent JP-A 11-273147, for example, can be used for this purpose.

The optical data carrier has, for example, the following layer structure (cf. FIG. 1): a transparent substrate (1), optionally a protective layer (2), an information layer (3), optionally a protective layer (4), optionally an adhesive layer (5 ), a cover layer (6).

The structure of the optical data carrier can preferably:

contain a preferably transparent substrate (1), on the surface of which at least one information layer (3) which can be written on with light and which can be written on with light, preferably laser light, optionally one

Protective layer (4), optionally an adhesive layer (5), and a transparent cover layer (6) are applied.

contain a preferably transparent substrate (1), on the surface of which a protective layer (2), at least one information layer (3) which can be written on with light, preferably laser light, optionally an adhesive layer (5), and a transparent cover layer (6) are applied.

contain a preferably transparent substrate (1), on the surface of which there is optionally a protective layer (2), at least one information layer (3) which can be written on with light, preferably laser light, optionally an Protective layer (4), optionally an adhesive layer (5), and a transparent cover layer (6) are applied.

contain a preferably transparent substrate (1), on the surface of which at least one information layer (3) which can be written on with light, preferably laser light, optionally an adhesive layer (5) and a transparent cover layer (6) are applied.

Alternatively, the optical data carrier has, for example, the following layer structure (cf. FIG. 2): a preferably transparent substrate (11), an information layer

(12), optionally a reflection layer (13), optionally an adhesive layer (14), another preferably transparent substrate (15).

The invention further relates to optical data carriers according to the invention described with blue or red light, in particular laser light.

The following examples illustrate the subject matter of the invention.

Examples

example 1

4 g of 2-amino-5- (diisopropylamino) -l, 3,4-thiadiazole were dissolved in 40 ml of glacial acetic acid. 8 ml of 85% by weight phosphoric acid and 6 ml of 48% by weight sulfuric acid were added dropwise at 10 ° C. 6.8 g of nitrosylsulfuric acid (40% by weight in sulfuric acid) were then added dropwise at 5 ° C. over 30 minutes. After 4 h at 0-5 ° C, the excess nitrite was destroyed with sulfamic acid.

This diazotization dripped at 10 ° C. for 1 h to a solution of 2.6 g of 2-dimethylaminothiazole in 30 ml of glacial acetic acid, a pH of 3 being maintained with 20% by weight aqueous sodium carbonate solution. After stirring overnight at pH = 3.5, the product was filtered off with suction and washed with water. The solid was stirred in 100 ml of water, adjusted to pH = 7.5 and suction filtered again and washed with water. After drying, the crude product was dissolved in 400 ml of tetrahydrofuran. The mixture was precipitated by slowly adding 400 ml of water with stirring, filtered off with suction, washed with water and dried. 4.5 g (66% of theory) of a red powder of the formula were obtained

Mp = 232-233 ° C λmax = 496 nm ε = 44140 1 / mol cm λι _{/ 2} -λι _/ ιo (long-wave flank) = 22 nm

Δλ = | λθMF - Dioxanl ⁼ 2 lim

Solubility:> 2% in TFP (2,2,3,3-tetrafluoropropanol) glassy film Suitable heterocyclic azo dyes are also listed in the table:

^l 'in dioxane unless otherwise stated.

²⁾ on the short-wave flank

³⁾ on the long-wave flank

Δλ = | λθMF - λüioxaiil

⁵⁾ in methanol / glacial acetic acid 9: 1 ⁶⁾ in DMF

Example 36

A 2% by weight solution of the dye of Example 11 in 2,2,3,3-tetrafluoropropanol was prepared at room temperature. This solution was applied to a pregrooved polycarbonate substrate using spin coating. The pregrooved polycarbonate substrate was manufactured as a disk using injection molding. The dimensions of the disc and the GiOove structure corresponded to that which is usually used for CD-R. The disk with the dye layer as the information carrier was sputtered with 100 nm silver. A UV-curable acrylic lacquer was then applied by spin coating and cured using a UV lamp. With a dynamic writing test setup, which was built on an optical bench, consisting of one

Diode laser (λ = 660 nm), for generating linearly polarized light, a polarization-sensitive beam splitter, a λ / 4 plate and a movably suspended converging lens with a numerical aperture NA = 0.6 (actuator lens). The light reflected from the reflection layer of the disk was coupled out of the beam path with the aid of the polarization-sensitive beam splitter mentioned above and focused on a four-quadrant detector by an astigmatic lens. At a linear velocity V = 2 m / s and a write power P _w = 20 mW, a signal-to-noise ratio C / N = 30 dB was measured. The write power was applied as an oscillating pulse sequence, the disk being alternately irradiated for 500 ns with the above-mentioned write power P _w and for 500 ns with the read power P _r - 2 mW. The disc was irradiated with this oscillating pulse sequence until it had turned around once. The marking generated in this way was then read out with the reading power P _r - 2 mW and the above-mentioned signal-to-noise ratio C / N was measured.

Claims

Patentansprtiche

1. Optical data carrier containing a preferably transparent substrate, which may already have been coated with one or more reflective layers, on the surface of which an information layer which can be written on with light, optionally one or more reflective layers and optionally a protective layer or a further substrate or a covering layer, which are applied with Blue or red light, preferably laser light, can be described and read, the formation layer containing a high-absorption compound and optionally a binder, characterized in that at least one heterocyclic azo dye is used as the light-absorbing compound.

2. Optical data carrier according to claim 1, characterized in that the heterocyclic azo dye corresponds to the formula (I)

wherein

K for the rest of a coupling component of the formula

- A _N A (IH) stands,

^X V

X ^{1 is} OrN or CH,

X ^{2 stands} for O, S. NR ⁹ or CH, but X ¹ and X ^{2 must} not simultaneously stand for CH,

1

A together with X and X and the C atom bonded in between represents a five- or six-membered aromatic or quasi-aromatic heterocyclic ring which contains 1 to 4 heteroatoms and / or benzylated or naphthanellated and / or can be substituted by nonionic radicals .

represents O or S,

X represents CR 1 ⁱ 0 ^υ or N,

R, R, R, R and R independently of one another represent hydrogen, Ci to C ₆ alkyl, C ₅ to C ₇ cycloalkyl, C ₆ to Cio aryl or C ₇ to C ₁₅ alkyl or

NO ^! R ² and NR ⁶ R ⁷ independently of one another represent pyrrolidino, morpholino, piperazino or piperidino,

R ³ and R ⁵ independently of one another for hydrogen, Ci to C ₆ alkyl, Ci to

C ₆ - alkoxy or halogen or R ³ ; R ² and R ⁵ ; R ^J independently form a two- or three-membered bridge which contain O or N and can be substituted by nonionic radicals,

R ⁴ for hydrogen, Ci to C ₆ alkyl, C to C ₆ alkoxy, halogen, Ci to

C ₆ -acylamino, Ci to C ₆ alkylsulfonylamino, C ₆ to Cio-arylcarbonylamino or C ₆ to Cio-arylsulfonylamino,

R ^{8 represents} hydrogen, Ci to C ₆ alkyl, halogen, C ₆ to Cio aryl, bis Ci to C ₆ dialkylamino, pyrrolidino, piperidino or morpholino and

R ^{10 represents} hydrogen, cyano, - to C ₆ -alkyl, halogen or C ₆ - to Cio-aryl.

3. Optical data carrier according to claim 2, characterized in that the rest of the formula (IV)

for benzthiazol-2-yl, benzoxazol-2-yl, benzimidazol-2-yl, thiazol-2-yl, isothiazol-3-yl, isoxazol-3-yl, imidazol-2-yl, pyrazol-5-yl, 1 , 3,4-thiadiazol-2-yl, l, 2,4-thiadiazol-5-yl, l, 2,3-thiadiazol-5-yl, 1,3,4-oxadiazol-2-yl, 1,3 , 4-triazol-2-yl, thiophen-2-yl, benzothiophen-2-yl, 2- or 4-pyridyl, 2- or 4-quinolyl, these radicals in each case by - to C ₆ -alkyl, Ci- to C ₆ alkoxy, fluorine, chlorine, bromine, iodine, cyano, nitro, C to C ₆ alkoxycarbonyl, Ci to C ₆ alkylthio, d to C ₆ acylamino, C ₆ to Cio aryl, C ₆ - to ₀ Cι oxy aryl, C ₆ - to Cio-arylcarbonylamino, mono- or di-Cr to C ₆ - Alkylamino, N-Ci to C ₆ alkyl-NC ₆ to C ₁₀ arylamino, pyrrolidino, morpholino, piperazino or piperidino can be substituted.

4. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (V)

wherein

X and X are independently C-R 12 or N.

R π for hydrogen, Ci to C ₄ alkyl, Cr to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio aryloxy, Cr to C ₄ alkylthio, mono- or bis-Ci - to C ₄ -alkylamino, N-Ci- to C ₄ -alkyl-NC ₆ - to Cιo-aryl-amino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci- to C ₄ -alkyl-NC - to C ^ -aralkylamino, Ci- to C -alkanoylamino, C ₆ - to Cio-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R 12 represents hydrogen, d- to C ₄ -alkyl, Ci to C ₄ -alkoxy, cyano, Cr to C ₄ -alkoxycarbonyl or C ₆ to Cio-aryl, or if X ^{6 represents} CR ¹² ,

R. l ^U l.; rR.1 ^X 2 together form a -CH = CH-CH = CH bridge, - SI ¬

NK. ¹ ) * ² for mono- or bis-Ci to C ₄ alkylamino, N-Ci to C -alkyl-NC ₆ - to Cio-arylamino, N-Cr to C -alkyl-NC ₅ - to C ₆ - cycloalkylamino, N-Cr to C-alkyl-NC - to Ci ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Ci to C - alkyl or Ci to C - alkoxy or

R ³ ; R ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or - CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ Bridge stand,

R ^{5 represents} hydrogen or

R ⁵ ; R ² together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or - CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ Bridge stand and

R is hydrogen, Cr to C ₄ alkyl, Cr to C ₄ alkoxy, chlorine, Ci to

C ₄ -alkanoylamino, N-Ci to C -alkyl-N-Ci- to C -alkanoylamino,

Ci to C ₄ alkylsulfonylamino, N-Cr to C ₄ alkyl-N-Cr to C -

Alkylsulfonylamino, C ₆ - to Cio-Aroylamino or C ₆ - to Cio-Arylsulfonylamino stands.

5. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (VI)

wherein X ^{5 represents} CR ¹² or N,

R ^{11 is} hydrogen, Ci to C ₄ alkyl, C to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio aryloxy, Cr to C ₄ alkylthio, mono- or

Bis-Ci to C-alkylamino, N-Ci to C ₄ -alkyl-NC ₆ - to C ₁₀ -aryl-amino, N-Cr to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N- Ci to C alkyl NC to Cπ aralkylamino, Ci to C ₄ alkanoylamino, C ₆ to Cio aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{12 represents} hydrogen, Cr to C alkyl, Ci to C ₄ alkoxy, cyano, nitro, Ci to C ₄ alkoxycarbonyl or C ₆ to Cio-aryl, or X ^{5 represents} C- R ¹² ,

R ¹¹ ; R ⁿ together form a -CH = CH-CH = CH bridge,

NO ^! R ² for mono- or bis-Ci to C ₄ -alkylamino, NC to C ₄ -alkyl-NC ₆ - to Cio-arylamino, N-Ci to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ alkyl-NC to Ci ₂ aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Ci to C ₄ alkyl or Ci to C ₄ alkoxy or

R ³ ; R ¹ together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or -

CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge,

R ^{5 represents} hydrogen or

R ⁵ ; R ² together for a -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ -, -O-CH ₂ -CH ₂ - or ^■

CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge and R ^{4 is} hydrogen, C to C ₄ alkyl, d to C ₄ alkoxy, chlorine, C to

C ₄ -alkanoylamino, N-Cr to C ₄ -alkyl-N-Cr to C ₄ -alkanoylamino,

C to C ₄ -Acylsulfonylamino, Nd- to C ₄ -alkyl-Nd- to C ₄ -alkylsulfonylamino, C ₆ to Cio-aroylamino or C ₆ to bis-arylsulfonylamino.

6. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (VII)

wherein

X ⁵ and X ⁶ independently of one another represent CR ¹² or N,

R ¹¹ for hydrogen, d- to C ₄ - alkyl, Ci to C ₄ - alkoxy, C ₅ - to C ₆ -

Cycloalkoxy, C ₆ - to do-aryloxy, Cr to C -alkylthio, mono- or

Bis-Ci to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to C ₁₀ -aryl-amino, N-Cr to C ₄ -alkyl-NC ₃ - to C ₆ -cycloalkylamino, N-Ci - to

C-alkyl-NC - to Cπ-aralkylamino, Cr to C ₄ -alkanoylamino, C ₆ - to Cio-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{12 is} hydrogen, d- to C ₄ -alkyl, C to C ₄ -alkoxy, cyano, C to

C ₄ -alkoxycarbonyl or C ₆ - to do-aryl or when X ^{6 is} C- R ¹² , _R n. _R ⁱ² together form a -CH = CH-CH = CH bridge,

R ^{13 represents} hydrogen, Cr to C alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ₁₂ aralkyl or C ₆ to C ₁₀ aryl,

NR ^L R ² for mono- or bis-d- to C ₄ -alkylamino, N-Cr to C ₄ -alkyl-NC ₆ - to Cio-arylamino, N-Cr to d-alkyl-Nd- to C ₆ -cycloalkylamino , N-Ci to C ₄ alkyl-NC ₇ to Ci ₂ aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Ci to C ₄ alkyl or Cr to C ₄ alkoxy or

R ^{5 represents} hydrogen or

R ⁴ for hydrogen, Ci to C alkyl, Cr to C alkoxy, chlorine, Ci to

C ₄ -alkanoylamino, N-Ci- to C -alkyl-Nd- to C ₄ -alkanoylamino,

Cr to C ₄ alkylsulfonylamino, N-Ci to C ₄ alkyl-Nd to C ₄ alkylsulfonylamino, C ₆ to Cio-aroylamino or C ₆ to do-arylsulfonylamino.

7. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (Vπi) wherein

R ^{11 is} hydrogen, d- to C ₄ -alkyl, d- to C ₄ -alkoxy, C ₅ - to C ₆ -cycloalkoxy, C ₆ - to C ₁₀ -aryloxy, d- to C ₄ -alkylthio, mono- or

Bis-Cr to C ₄ -alkylamino, N-Ci to C ₄ -alkyl-NC ₆ - to do-arylamino, N-Cr to C ₄ -alkyl-N-Cs- to C ₆ -cycloalkylamino, N- Ci to C ₄ alkyl NC to Ci ₂ aralkylamino, Ci to C ₄ alkanoylamino, C ₆ to Cio aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{13 represents} hydrogen, Cr to C ₄ alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ₁ 2 aralkyl or C ₆ to do aryl,

NO ^! R ² for mono- or bis-Cr to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to cio-arylamino, N-Cr to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N -Ci to C ₄ alkyl-NC ₇ to Cπ-aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{3 represents} hydrogen, Cr to C alkyl or d to C alkoxy or

R ³ ; R ¹ together represent a -CH ₂ -CH ₂ -, -CH2-CH2-CH2-, -O-CH ₂ -CH ₂ - or - CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge .

R ^{5 represents} hydrogen or R ⁵ ; R ² together represent a -CH ₂ -CH ₂ -, -CH2-CH2-CH2-, -O-CH ₂ -CH ₂ - or - CH (CH ₃ ) -CH ₂ -C (CH ₃ ) ₂ bridge and

R ⁴ for hydrogen, Cr to C alkyl, Ci- to C ₄ alkoxy, chlorine, Ci to C ₄ alkanoylamino, N-Ci to Q alkyl-N-Cr to C ₄ alkanoylamino, Cr to C _4- alkylsulfonylamino, N-Ci to C-alkyl-N-Cr to C - alkylsulfonylamino, C ₆ - to Cio-aroylamino or C ₆ - to do-arylsulfonylamino.

Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (LX)

wherein

X and X independently of one another represent C-R 12 or N,

R π for hydrogen, Ci to C ₄ alkyl, Cr to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to do aryloxy, Cr to C alkylthio, mono- or bis-Ci- to C ₄ -alkylamino, N-Cr to C -alkyl-NC ₆ - to C ₁₀ -aryl-amino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, Nd- to C ₄ - Alkyl-NC ₇ - to Ci2-aralkylamino, Cr to C ₄ -alkanoylamino, C ₆ - to Cio-aroylamino, pyrrolidino, piperidino, piperazino or morpholino, R ^{12 stands} for hydrogen, Cr to C ₄ alkyl, d to C ₄ alkoxy, cyano, Ci to C ₄ alkoxycarbonyl or C ₆ to C ₁₀ aryl or if X stands for C- R ¹² ,

R ¹¹ ; R ¹² together form a -CH = CH-CH = CH bridge,

X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-d- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to do-arylamino, N-Ci to C ₄ -alkyl-NC ₅ - to C ₆ cycloalkylamino, N-Ci to C ₄ alkyl-NC ₇ to Ci ₂ aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, Ci to C ₄ alkyl, chlorine, C ₆ to C ₁₀ aryl, bis-d to C ₄ dialkylamino, pyrrolidino, piperidino or morpholino.

9. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye of the formula

(X) corresponds

wherein

X ^{3 represents} CR, 1 ¹ 2 or N, R ^{11 is} hydrogen, Ci to C ₄ alkyl, Cr to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to C ₁₀ aryloxy, d to C ₄ alkylthio, mono- or bis -Ci to C -all ylamino, N-Cr to C ₄ -alkyl-NC ₆ - to C ₁₀ -aryl- amino, N-Ci to d-alkyl-N-Cs- to C ₆ -cycloalkylamino, N- Ci to C alkyl NC ₇ to Ci ₂ aralkylamino, Cr to C ₄ alkanoylamino, C ₆ to Cio aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{12 represents} hydrogen, Cr to C ₄ alkyl, Ci to C ₄ alkoxy, cyano, nitro, Ci to C ₄ alkoxycarbonyl or C ₆ to Cio-aryl, or if X ^{5 represents} CR ¹² ,

R ^{1 λ} ; R ¹² together form a -CH = CH-CH = CH bridge,

X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-d- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to cio-arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ cycloalkylamino,

N-Ci to C ₄ alkyl-NC ₇ to Ci ₂ aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, d- to C ₄ -alkyl, chlorine, C ₆ - to cio-aryl, bis-d- to C ₄ -dialkylamino, pyrrolidino, piperidino or morpholino.

10. Optical data carrier according to one or more of claims 1 to 3, characterized in that the heterocyclic azo dye corresponds to the formula (XI) wherein

X ⁵ and X independently of one another represent CR or N,

R ^{11 is} hydrogen, Ci to C ₄ alkyl, d to C ₄ alkoxy, C ₅ to C ₆

Cycloalkoxy, C ₆ - to C ₁₀ -aryloxy, Cr to C -alkylthio, mono- or

Bis-Cr to C ₄ -alkylamino, N-Cr to C ₄ -alkyl-N-C6- to do-arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N- Ci to C ₄ alkyl NC ₇ to Cπ-aralkylamino, Cr to C ₄ alkanoylamino, C ₆ to do-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{12 represents} hydrogen, Cr to C ₄ alkyl, Ci to C ₄ alkoxy, cyano, Cr to C alkoxycarbonyl or C ₆ to Cio-aryl, or if X ^{6 represents} C-

R ¹² stands for or if X ^{5 stands} for CR ¹² ,

R ^π ; R ¹² together form a -CH = CH-CH-CH bridge,

R ¹³ for hydrogen, d- to C ₄ -alkyl, C ₅ - to C ₆ -cycloalkyl, C ₇ - to C ₁₂ -

Aralkyl or C ₆ - to Cio-aryl,

X ^{3 represents} O or S,

X ^{4 represents} CH or N, NR ⁶ R ⁷ for mono- or bis-d- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to cio-arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Ci to C ₄ -alkyl-NC to C ^ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ^{8 represents} hydrogen, Cr to C ₄ alkyl, chlorine, C ₆ to C ₁₀ aryl, bis-Ci to C ₄ dialkylamino, pyrrolidino, piperidino or morpholino.

11. Optical data carrier according to one or melireren of claims 1 to 3, characterized in that the heterocyclic azo dye of the formula

(XII) corresponds

wherein

R n is hydrogen, Ci to C ₄ alkyl, Cr to C ₄ alkoxy, C ₅ to C ₆ cycloalkoxy, C ₆ to Cio-aryloxy, Ci to C ₄ alkylthio, mono- or bis- d- to d-alkylamino, N-Cr to C -alkyl-NC ₆ - to C ₁₀ -aryl-amino, N-Ci- to C -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Cr to C ₄ -Alkyl-NC - to Ci ₂ -aralkylamino, Cr to C ₄ -alkanoylamino, C ₆ - to do-aroylamino, pyrrolidino, piperidino, piperazino or morpholino,

R 13 represents hydrogen, Ci to C ₄ alkyl, C ₅ to C ₆ cycloalkyl, C ₇ to C ₁₂ aralkyl or C ₆ to C ₁₀ aryl, X ^{3 represents} O or S,

X ^{4 represents} CH or N,

NR ⁶ R ⁷ for mono- or bis-Ci- to C ₄ -alkylamino, Nd- to C ₄ -alkyl-NC ₆ - to cio-arylamino, N-Ci- to C ₄ -alkyl-NC ₅ - to C ₆ -cycloalkylamino, N-Cr to C ₄ -alkyl-NC - to -C ₂ -aralkylamino, pyrrolidino, piperidino, piperazino or morpholino,

R ⁸ for hydrogen, d- to C ₄ -alkyl, chlorine, C ₆ - to cio-aryl, bis-d- bis

C ₄ dialkylamino, pyrrolidino, piperidino or morpholino.

12. Use of heterocyclic azo dyes in the information _{layer of write-} once optical data carriers, the heterocyclic azo dye having an absorption maximum λ _max in the range from 420 to 650 nm.

13. Use of heterocyclic azo dyes in the information layer of write-once optical data carriers, the data carriers being written on and read with a blue laser light.

14. A method for producing the optical data carrier according to claim 1, which is characterized in that a preferably transparent substrate, optionally already coated with a reflection layer, is coated with the heterocyclic azo dyes, optionally in combination with suitable binders and additives and optionally suitable solvents, and optionally with a reflection layer, further intermediate layers and optionally a protective layer or another substrate or a covering layer.

15. Optical data carrier according to claim 1 described with blue or red, in particular blue light, in particular blue laser light.

16. Heterocyclic azo dyes of the formula (X), (XI) or (XII)

wherein the radicals X ³ to X ⁶ , R ⁶ to R ⁸ and R ¹¹ to R ^{13 have} the meanings given in claims 9, 10 and 11.