DE3801546A1 - Optical information-recording medium, and process for the production thereof - Google Patents

Abstract

The invention relates to an optical information-recording medium having a thin film of an organic dye as recording layer, in which the organic dye is a high-molecular-weight organic dye which is, for example, a copolymer of an organic dye with a polymerisable compound. It may be in the form of a mixture with a normal organic dye.

Description

The invention relates to optical information recording media, especially of the writing type, with thin films organic dyes, which have a higher stability sen, and processes for their preparation.

A type of optical information recording media are writing-type information recording media, at those heat-sensitive, organic on a substrate Recording layers containing dyes are present. This type of optical information recording media is advantageous because the recording layers with conventional applied coating process and thus the Her service costs can be reduced; they are also like that produced recording layers much more durable against oxidation as layers of thin metal films. Furthermore, the thermal conductivity of synthetic resins in the United States equal to metals, so that the distances between the  Depressions (pits) reduced and thus the record density can be increased.

Optical information recording media, the recording contain films from organic dyes Although the advantages described above, the stability of the dyes used is a problem so that secure information storage for a long time is uncertain.

That is why heat-sensitive recording media with recording layers from the orga described above tries to use anionic quenchers to be added as stabilizers. For polymethine dyes protective polymer films were formed on the dye films det to the stability of the thin, the dyes contain tend to improve films. By adding anioni The extinguisher as stabilizers is the dye content in the recording film so that the light absorpt tion properties or reflectivity, which the Influence recording properties, are reduced. If a polymeric protective film is present, this becomes inaccurate pits because the protective film itself does not Has light absorption and only little thermal expansion chung. Both methods increase stability, however, reduce the efficiency of the recording that a is the decisive criterion for record carriers. This way the problem could not be solved.

Because of the reduction in information recording properties  due to the progressive crystallization of organic dyes in heat-sensitive optical Information recording media caused has been ver suggests that the addition of certain polymers is effective could be. From the standpoint of improving stability it is desirable to add a polymer that is not a color is fabric; the amount of dye in the thin recording however, film decreases through the addition of the polymer, too are for an optical information recording medium essential recording properties, such as life duration, deteriorating, causing fundamental problems such as Decrease in sensitivity to laser light or low reflectivity of the recording film, ent stand. In addition, the molecular mass of the differs Dye in the thin recording film very from the mole cooling mass of the polymer to be added, so that after the Vermi microscopic phase separation to a macrosco phase separation. That's why not even that Stability satisfactory in itself.

Known exemplary embodiments of this type are, for example Recording films with a single dye on which as a protective layer, a thin film of polystyrene and the like. is applied (JP 58-36 490 A1), cyanine dye films with a synthetic resin layer provided thereon (JP 59-203252 A1), or dye polymers as recording films, such as e.g. B. thermoplastic vinyl polymers with dye residues (JP 59-45195 A1), styrene polymers with a phthalocyanine residue in the side chain (JP 59-62188 A1), polymers with phthalocya residual in side chains and a styrene main chain  an average molecular weight of 40,000 or less (JP 59-71894 A1), polymers with phthalocyanine rings in the Main chain (JP 59-73994 A1), dye polymer or ent speaking compositions with this dye polymer (JP 59-185694 A1), polymers of a cyanine dye Indole rings on both chain ends (JP 59-188853 A1), Synthetic resins with indole rings on both chain ends and one Cyanine dye in side chains (JP 59-188854 A1), art resin with and on an acidic anion in side chains bound a cyanine cation (JP 59-188855 A1), light absorber agents and synthetic resins with a functional group, which are cross-linked via a metal cross-linking agent are (JP 59-201243 A1), two synthetic resins with functional Groups cross-linked via a metal cross-linking agent are (JP 59-201244 A1), polymers in which a dye contains a group -COO- or at least two -COO groups (JP 59-229396 A1), dye polymers (JP 59-230796 A1), Polymers of a dye and a synthetic resin (JP 59-232894 A1) and compositions with a dye and a synthetic resin component (JP 59-232896 A1). With these known materials is a single dye chemical linkage bound to high molecular substances (see JP 59-188853 A1, 59-188854 A1, 59-62188 A1 and 59-71894 A1).

The object of the invention was therefore an optical informa tion recording medium and its production, who do not experience the problems listed above.

The object is achieved according to claims 1 and 14. The  Subclaims relate to advantageous embodiments.

In an embodiment according to the invention, a becomes high molecular dye by binding an organic dye to a polymerizable monomer and polymerizing of the resulting connection. You can statistical copolymerizations or graft copolymers ions are used.

The optical information recording according to the invention medium with a thin film of an organic dye is marked as a record carrier through a recording layer made of a high molecular weight organic dye, which is a copolymer of an organic Represents dye with a polymerizable monomer, possibly in a mixture with an organic dye.

According to a second embodiment of the invention the optical information recording medium Protective layer with light absorbing and reflecting Properties on a thin organic dye film as a recording layer. This will record protection layer and at the same time the Protective layer itself optical recording properties awarded.

According to another inexpensive development, the opti characterized by the information recording medium net that the film of a single organic dye with a high molecular dye coated by  Copolymerization of an organic dye monomer and a polymerizable monomer such as styrene, acrylic acid or methacrylic acid and its esters. This creates a protective layer on top of the dye drawing film before.

The absorption spectra of the high molecular color substance in which the same dye is used as it for information recording in optical information recording drawing media with low molecular weight dye alone used are not very different from the Ab sorption spectra of this dye alone; the mole kular dye has the properties of a Recording film. That is, the high molecular color fabric, the z. B. by copolymerization of an organic Dye with a polymerizable bonded to it Group with a polymerizable compound such as styrene, Acrylic acid or methacrylic acid and their esters available not only acts as a protective layer, but also shows Light absorption and light reflection properties. Therefore, the protective layer itself can be used as optical information recording medium can be used. The protective layer can work very well with the dye film form clear pits and thus provide a good medium excellent stability and good recording properties represent. Since the high molecular weight according to the invention Dye does not have to be very well tolerated by the dye as with conventional information recording media, in those with a low molecular weight dye as such with a Polymer is mixed, who feared phase separation  the. The information recording medium according to the invention, by adding this high molecular weight dye has excellent optical recording characteristics regarding all aspects of the initial Recording and playback, the recording and re-recording properties after aging (forced deterioration tion), durability, and the like, compared to on drawing films containing an organic dye and be contain certain polymers. Since he is the crystallization of the Prevents dye from aging, demonstrates this according to the information recording medium substantially bes properties than on recording media in which a polymer was added to the dye film.

The invention is described below with reference to the drawings explained in more detail; show it:

Fig. 1a is a double-sided image plate, which is obtained by gluing together two inventive image plates, each plate having a recording film with a protective film laminated thereon and an adhesive on the protective film sides;

Figure 1b is a double-sided optical disk, with an air gap therebetween in which a second recording film is laminated on the first film-voltage Aufzeich.

Fig. 1c shows a double-sided optical image plate with an air gap, a single optical disk used in the two parts having a hub in the middle and the respective optical disks are mounted on both sides of the hub (ie hub A and B).

Fig. 2 is an enlarged view of a recording film and a protective film on a transparent substrate and a pre-pit on the surface of the recording film.

The image plate section of FIG. 2 shows a substrate 1, a pit 2, a recording film 3 and a protective film 4.

The recording films shown in Figs. 1 and 2 may either consist of a single high-molecular dye or a mixture of the high-molecular dye and a low-molecular dye as such. The protective film consists of a single, high molecular weight dye.

To produce the optical informa according to the invention tion recording medium becomes an organic dye reacted with a polymerizable monomer, whereupon the polymerizable dye monomer by statistical or Graft copolymerization is polymerized. By adding this high molecular weight organic dye into one  low molecular weight dye as such becomes a thin one Recording film made.

A protective film having light-absorbing and reflecting properties is applied to the thin film of the organic dye as the recording layer in order to protect the recording film and at the same time impart optical recording properties to the protective layer. In the first stage of the process according to the invention, polymerizable dye monomers (hereinafter also referred to as macromonomers), by reaction of dye molecules with a chromophore with polymerizable monomers, by e.g. B. esterification. Examples of polymerizable monomers which can be used in the process according to the invention are
Acrylic monomers such as acrylic acid, acrylic acid ester, meth acrylic acid or methacrylic acid ester;
Styrene monomers such as styrene, α- methylstyrene, divinylbenzene, chlorostyrene, cyanostyrene, aminostyrene or hydroxystyrene;
Acrylamide monomers such as acrylamide, methacrylamide or diace tonacrylamid;
Fatty acid vinyl ester monomers, such as vinyl acetate or vinyl esters;
Nitrile and isonitrile monomers, such as acrylonitrile, methacrylonitrile, adiponitrile, phthalonitrile or isonitrile;
Vinyl ether monomers, such as alkyl vinyl ether,
halogenated olefinic monomers such as vinyl chloride, vinyl chloride, vinyl bromide, vinylidene bromide, vinyl fluoride or vinylidene fluoride;
conjugated diene monomers such as butadiene, isoprene, chloroprene, fluoroprene or cyanoprene;
N-vinyl monomers
and olefin monomers such as ethylene, propylene, isobutylene and the like.

Phthalocyanines such as manganese tetra-t butyl phthalocyanine or vanadium tetra-t-butyl phthalocya nin, naphthocyanines, such as manganese tetra-t-amylnaphthocyanin and vanadium tetra-t-amylnaphthocyanine can be used.

The organic dye monomers are polymerized with monomers to high molecular weight organic dyes copolymerized statistically or by grafting.

In graft copolymerization, the copolymerization depends from the main chain of the polymerizable mono used meren from; with polyacrylic acid z. B. the carboxyl groups the main chain by esterification to the organic Dye bound. In statistical copolymerization can, for example, with the so-called macromonomers, the polymerizable by converting the dye  Dye monomers are available, different Eigen depending on the type of polymerizable used Monomers can be achieved. So by copolymerization a styrene dye macromonomer and an acrylic acid Dye macromonomer copolymers with styrene and acrylic acid units in the main chain can be obtained. By Changing the monomer and the copolymerization ratio can produce the desired high molecular weight dyes be put. By copolymerizing an acrylic acid Dye macromonomer with an acrylic acid glycidyl ester Monomer can be a high molecular weight epoxy group containing Dye are made, for example, with acids or amines can be crosslinked, making it applicable and its properties are expanded.

The following compounds can be used as initiators for radial polymerization:
Azo compounds such as azo-bis (isobutyronitrile),
Peroxides, such as benzoyl peroxide, di-t-butyl peroxide or potassium persulfate,
aqueous redox initiators, such as cumene hydroperoxide and amines,
non-aqueous redox initiators, such as hydrogen peroxide, benzoyl peroxide and dimethylaniline or cobalt naphthenate.

In the case of polymerization initiated by radiation can use photoinitiators, such as UV light sensitizers  or visible light.

Examples of suitable dyes are:
Methine, polymethine, cyanine, carbocyanine, anthraquinone, azo, phthalocyanine, naphthocyanine, squalenium or azu lenium dyes.

The dye molecule can be bound to the polymerizable monomer directly or, for example, via one of the following groups:
-O-, -CO-, -COO-, -OCO-, -SO₂-, -OCOO-, -NR-, -CONR-, -CONRCO-, -NRCO-, -S-, -SO₂NR- or -RSO₂ -,
where R is hydrogen or alkyl.

The polymerizable monomer and dye can be on following different ways to be connected, where M is the monomer and D is the dye:

• 1. Monomer and dye are individually linked to form large molecules:
• 2. A monomer without dye and a monomer with a dye attached to it are simultaneously linked to form large molecules: respectively.
• 3. The high molecular chains contain polymerized Dye units: -M-D-M-D-or-M-M-D-D-D-
• 4. The high molecular chains contain polymerizable monomers, polymerizable dye monomers, dye polymer groups or a polymerizable dye: respectively.

The monomers do not have to be the same.

A ratio of organic dye monomer A to mono mer B in the range of 1 to 30, generally 2 to 20 and preferably 3 to 15 mol of organic dye monomer A each 100 mol of monomer B is suitable. For cyanine macromonomers are preferably 10 to 20 and in particular 10 to 15 mol used. For phthalo- and naphthocyanine macromonomers 2 to 10 and preferably 3 to 8 mol are added  puts. Depending on the use, the monomers can also be in Amounts outside of these ranges are used.

Combinations of polymerizable monomer and dye preferably include acrylic acid monomers such as acrylic acid or methacrylic acid, and various acrylates and Methacry late, and phthalocyanine macromonomers, styrene monomers, at play as styrene or α-methylstyrene, and cyanine macro monomers and monomers having an ethylenic bond, such as vinyl chloride , and phthalocyanine macromonomers.

The reaction is conventional among those at Block polymerizations or statistical polymerizations applied conditions.

The high molecular dye and color thus produced Substance monomer A are used as the material for the recording Use film of the optical information recording medium det. Doing so

• 1. a film by mixing the high molecular dye and the organic dye monomer A. respectively.
• 2. a laminate of a film of the high molecular dye and a film of dye monomer A.

The mass ratios of the components in question can in the range of 0 to 80 parts by mass of dye monomer and 20  up to 100 parts by weight of high molecular weight dye at Verwen as a protective film and in the range of 20 to 100 parts by mass Dye monomer and 0 to 80 parts by weight of high molecular weight Dye can be chosen.

If the recording medium is used under conditions among which the recording power is large enough, so can the high molecular dye alone, without dye monomeric are used, the mass ratios then can be selected from the ranges specified above nen.

The recording film and the protective layer are preferred have a thickness in the range of 5 to 500 nm (50 to 5000 Å) and especially from 10 to 60 nm (100 to 600 Å).

If a recording medium made of a substrate, a first protective film and a recording film is formed, a second protective film should be formed Protective films the sensitivity of the recording film not significantly affect.

Absorbs a dye used in these protective films strong in the visible or UV range, so it is possible Lich, the aging of the optical recording medium rend during storage, however, the color should concentration of substances in the polymeric protective films and Thickness of each protective film should be such that the sensitivity or the signal-to-noise ratio is not appreciably impaired are required.  

The present high molecular weight record The film with the high molecular dye can be the first Protective film and / or used as a second protective film the. If a recording film and a second protective film formed in this order, so points the second protective film has the following properties:

Is the light absorption spectrum one in the protective film dye used the same or similar to that of the Auf drawing film, so is the formation after laser irradiation of pits with a clear margin clearly stated that the polymeric dye protective film on the recording film was formed even though the recording sensitivity more or less with the dye concentration of the color polymer in the protective film and with the thickness of the Protective film varies. In addition, the stability against can be significantly improved above the reading light.

From the high molecular dye materials and dye The following combinations of monomer materials are preferred:

Carbocyanine dyes are among the dyes for optical Record with the highest reflectance. At Mixing a carbocyanine dye of the same kind as acrylic acid macromonomer carbocyanine dye into one Recording film, the spectrum is identical, so that on drawing media with good thermal stability, good Light absorption and reflection properties and thus high recording sensitivity are accessible.  

The invention is illustrated below by examples.

Example 1

Polymerizable monomers, in which dye molecules with a chromophore with acrylic acid or methacrylic acid mono meren are connected by esterification, for example use the following formula:

where R is COOH, H, alkyl, acryloyl, an alkyl ester group, Phenyl, a phenyl ester group, a residue with terminal Is COOH or H or alkoxy. In this example, R OCOC₄H₉.

Another suitable polymerizable monomer A can by reacting a manganese phthalocyanine derivative with  monomeric styrene can be obtained in a conventional manner, has the following structural formula:

where R has the meaning given above.

This manganese phthalocyanine derivative is first with a Monomer B, such as acrylic acid, methacrylic acid or styrene set (the substituent R can then polymerize in the bare monomer A are introduced). The COOH groups can remain unesterified. The synthesis of the polymerizable Monomer A can, for example, turn blue according to the following scheme fen:  

The polymerizable monomer (A) thus obtained is reacted in a solvent such as dimethyl sulfoxide together with methyl acrylate (B) in the presence of a polymerization initiator such as azobis (isobutyronitrile) in a manner corresponding to conventional radical polymerization with heating to give a copolymer. The ratio of A to B is given in Table 1:
Sample A: B 1 1: 100 2 3: 100 310: 100 420: 100 530: 100 640: 100

On a plate substrate made by coating a glass substrate obtained with the 2P method is the one above specified phthalocyanine dye alone, d. H. a solution of Mn-phthalocyanine (R = OCOC₄H₉) in chloroform into one thin dye film with a thickness of 60 nm through Rotary coating applied. A solution to the before Mn-phthalocyanine-methyl acrylate copolymer produced in Methyl isobutyl ketone is applied to this layer as protection layer with a thickness of 10 nm by spin coating tion applied. In this way, an optical information mation recording film with a total thickness of 70 nm educated. The recording film is described with a Semiconductor laser with a wavelength of 830 nm and one Power of 7 mW. In samples 1 and 2 of table 1 is the edge of the pits not sharp; the pits of samples 3 to 6 have a sharply defined shape, like a film of a single dye can be obtained.

The stability to light is with a lightfast measured by the tester. In each of samples 1 to 6, the  Degree of bleaching low compared to a Mn-Phthalo cyanine film (hereinafter abbreviated to Mn-PC) alone, while at the same time the stability is improved. On the other hand are neither the light absorption nor the reflection deteriorated, and the recording and re-recording Efficiency is as high as that of Mn-PC film alone.

However, if the thickness of the protective film is 10 nm or more, for example about 50% of the total thickness of the record carrier film, so it is better if the dye proportion in the high molecular color used as a protective film fabric is large, d. that is, it should be in the range of samples 3 to 6 of Table 1.

The dye used to prepare the high molecular dye and the dye used alone should preferably be the same; even if they are different, dyes with a light absorption spectrum of λ max = 830 nm can be used. Any combination of dyes is possible as long as the ability of the dyes to form pits is approximately the same and their overall properties are good.

Comparative Example 1

With the dye of Example 1, an optical information tion recording medium with a protective layer a thickness of 10 nm. The thin film is on the Plate substrate prepared according to Example 1 and with a Nitrocellulose solution in cyclohexane with a viscosity of 0.5 s coated. The film is made according to Example 1 with a  Laser described. The pits have a clearly deformed Edge, as if the surface layer had cracks. The Recording can only be done with a low signal / noise Distance. It can be seen from this that this medium is not suitable for practical use is.

Example 2

From the ingredients listed in Table 2, i.e. H. high molecular vanadyl-tetra-t-amylnaphthocyanin (A) and Vana dyl-tetra-t-amylnaphthocyanin (B) becomes a recording film made. In Table 2:

A: high molecular weight vanadyl-tetra-t-amylnaphthocyanine, the consists of 30 parts by weight of polymerizable monomer, by adding vanadyl-tetra-t-amylnaphthocyanine to acrylic acid and 100 parts by weight of methyl acrylate monomer is available B: vanadyl-tetra-t-amylnaphthocyanin, C: the reflectance at 830 nm before the aging test and D: the reflectance at 830 nm after 1000 h at 60 ° and 90% humidity.  

Table 2

Comparative Example 2

In Table 3, E means a nitrocellulose solution with a Viscosity of 0.5 s; the other details correspond to Ta belle 2.

Table 3

With a mixing ratio of high molecular weight vanadyl tetra-t-amylnaphthocyanine to vanadyl-tetra-t-amylnaphtho cyanine from 1 to 50: 100 parts by weight is the reflection degrees high, and the decrease in reflectance after 1000 h at 60 ° C and 90% humidity is low. Out of it  it can be seen that this range is preferred.

On the other hand, if nitrocellulose (with a nitrogen content of 12%) with a viscosity of 0.5 s (according to JIS- Norm K-6703) as in Comparative Example 2 (Table 3) give, the reflectance decreases after storage of 1000 h at 60 ° C and 90% humidity; he is however lower before the aging test. Samples 6 and 7 of the comparative example show that the decrease in the Reflectance after the aging test is significant; the Recording film is therefore for practical use not suitable. The degree of reflection is measured with an ul breaks ball and based on the normal reflectance certainly.

Example 3

On a plate substrate that is coated by coating a Glass substrate obtained with the 2P method becomes one Solution of vanadyl-tetra-t-amylnaphthocyanine in cyclohexane by spin coating to a thin dye film upset. A solution of the previously made color fabric polymer in toluene in the composition according to Ta Belle 4 is applied to this film by spin coating upset.

The thickness of the dye recording film and the color Fabric polymer films are 60 and 10 nm. As a comparison becomes a nitrocellulose solution with a viscosity of 0.5 s (according to JIS standard K-6703) by spin coating the dye recording film in a thickness of 10 nm  applied after drying.

Table 4

In Table 4:

A: polymerizable, vanadyl-tetra-t-amylnaphthocyanine containing monomer; B: methyl acrylate; C: reflectance at 830 nm before the aging test; D: reflectance at 830 nm after 1000 h at 60 ° C and 90% Humidity.

From Table 4 it can be seen that the reflectance of the Samples 1 to 6 at 830 nm after 1000 h at 60 ° C and 90% Humidity decreases less than in the comparative example, which the higher stability of the recording according to the invention  medium confirmed. The degree of reflection is with a Ulbricht ball and based on the normal reflectance certainly.

In summary, it follows that according to the invention organic Dyes by polymerization, such as statistical copolyme risation or graft copolymerization, with a polymeri sizable monomer can be made high molecular weight. These high molecular weight organic dyes then become if necessary mixed with low molecular weight individual dyes and processed into thin recording films. To this This may result in the deterioration of the recording characteristics shafts based on the crystallization of organic color substances based, are prevented, furthermore the Stabili of the recording medium increased significantly without the Deteriorate recording properties. In addition, protective layers with light-absorbing and light-proof reflective properties on thin, organic Recording films containing dye are produced, whereby the recording films are protected and at the same time the protective layers have optical recording properties be awarded. The stability of such recording media can thus be increased significantly without the informa deterioration recording properties.

Claims (16)

1. Optical information recording medium with a thin film of an organic dye as a recording layer, characterized in that the organic dye is a high molecular weight organic dye. 2. Information recording medium according to claim 1, characterized characterized in that the recording layer next to the high molecular weight organic dye one or more contains low molecular dyes. 3. Information recording medium according to claim 1 or 2, characterized in that the high molecular weight organi dye is a copolymer of an organic color material with one or more polymerizable compounds is. 4. Information recording medium according to one of the claims 1 to 3, characterized in that the high molecular weight  organic dye a graft copolymer of an organic rule dye with one or more polymerizable Compounds and one or more polymerizable Dyes. 5. Information recording medium according to claim 3 or 4, characterized by a high molecular dye the base of a graft copolymer in which the main chain from monomer units of one or more polymerisable Monomer and possibly monomer units of one or more Dyes built up with polymerizable groups is. 6. Information recording medium according to claim 5, characterized characterized in that the pendant dye moles cool directly or via -O-, -CO-, -COO-, -OCO-, -SO₂-, -OCOO-, -NR-, -CONR-, -CONRCO-, -NRCO-, -S-, -SO₂NR- or -RSO₂- to the monomer units of the poly merizable monomers are bound. 7. Information recording medium according to one of the claims 1 to 6, characterized by a laminate of an organic the dye layer and a layer of high molecular weight laren organic dye as a recording layer. 8. Information recording medium according to one of claims 1 to 7, characterized by a high-molecular dye which has one of the structures below, where M is the monomer unit of a polymerizable monomer and D is the dye molecule, optionally via one of the groups specified in claim 6 a monomer unit M is bound mean: 9. Information recording medium according to one of the claims 1 to 8, characterized by a layer of high mole kular organic dye between a transparent term substrate and an organic dye layer. 10. Information recording medium according to one of the claims 1 to 9, characterized in that the organic Dye layer a high molecular organic color fabric contains and up on a layer of another molecular organic dye is laminated.   11. Information recording medium according to one of the claims 1 to 10, characterized by a high molecular weight organic dye obtained by the implementation of an orga African dye with a polymerizable monomer and polymerizing the composite thus obtained Monomers is made. 12. Information recording medium according to one of the claims 1 to 11, characterized by a layer of high molecular organic dye as protection layer of the recording layer. 13. Information recording medium according to one of the claims 1 to 12, characterized in that the organic Dye is a manganese or vanadium phthalocyanine and / or -naphthocyanin and / or a cyanine dye is. 14. Information recording medium according to one of the claims 1 to 13, characterized in that the high mole kular organic dye is a copolymer of one or several organic dyes with an acrylic, meth is acrylic, styrene and / or vinyl monomer. 15. A method for producing the optical information recording medium according to one of claims 1 to 14, characterized by

• a) reacting an organic dye with a polymerizable monomer and polymerizing and / or copolymerizing the polymerizable dye monomer obtained in the presence of a solvent and a polymerization initiator,
• b) optionally preparing a mixture of the copolymer prepared in step a) and an organic dye in a solvent,
• c) coating a substrate with the copolymer prepared in step a) in a solvent or with the mixture of the copolymer prepared in step b) and an organic dye in a solvent.

16. A method for producing the optical information recording medium according to one of claims 1 to 14, characterized by

• a) reacting an organic dye with a polymerizable monomer and polymerizing the polymerizable dye monomer obtained in the presence of a solvent and a polymerization initiator,
• b) coating a substrate with a solution of an organic dye to form a thin film and
• c) coating the organic dye film with the copolymer prepared in step a) medium in a solvent.