JPS62165648A - Optical recording medium - Google Patents

Abstract

PURPOSE:To improve the sensitivity by using a specified org. metallic complex as an infrared absorbing dye. CONSTITUTION:One or more kinds of org. metallic complexes represented by the formulae I-VI are used as an infrared absorbing dye. In the formulae, each of X and X' is H, alkyl or the like, each of Y, Y', Y'' and Y''' is H, alkyl, phenylor cyano, each of Z and Z' is H, alkyl or halogen, each of E and E' is H, alkyl phenyl or the like, each of G and G' is H, alkyl or halogen, and M is Ni, Co, Pd or Pt. The org. metallic complexes are kneaded with a dispersion medium such as transparent plastics and used in the form of a film or a sheet. The complexes may be dissolved in a solvent and applied to a substrate.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to optical recording media.

(Prior art) As a recording material for optical discs, a perforated optical recording material with a recording layer made of an inorganic material such as a metal or a metal oxide has been known. When recording, it has low sensitivity due to its high thermal conductivity and high melting point.
A high-power laser is required.

Furthermore, when using a semiconductor laser, the lifetime of the laser may be shortened due to its high output. moreover,
When these are used as a recording layer, there is also a problem in the reliability of recorded information due to deterioration due to oxidation. In addition, chalcogen metals, which are widely used among these, are toxic.

There is also the risk of causing environmental pollution. In addition to vapor deposition, it is cheaper than inorganic materials such as metals and metal oxides.

Such as coating method and dipping method. There are also examples of using organic materials as the recording layer, which allow easier film formation, have low thermal conductivity, and allow effective use of incident energy. However, in most cases, the absorption maximum is in the visible light region, and there are few that can be used with semiconductor lasers. Dyes that have absorption in the range that can be used by semiconductor lasers generally have low stability against heat, so storage stability remains a problem.

Furthermore, in the perforation type recording method, there is a possibility that the evaporated substances may adhere to other parts of the surface of the recording layer or contaminate the optical system. Furthermore, in drilling dies, the S/N ratio depends on the shape of the bit.

The material needs to be such that the bit can be formed neatly.

(Problems to be Solved by the Invention) The present invention provides a highly sensitive organic recording material using a recording method that utilizes a change in light absorption without causing a change in shape during recording.

(Means for Solving the Problems) The present invention provides an optical dye containing a near-infrared absorbing dye that absorbs in the oscillation wavelength region of a semiconductor laser and an initiator or initiator system that generates radicals by actinic rays. In the recording medium, the near-infrared absorbing dye has the following general formula (I), (I
The present invention relates to an optical recording medium made of an organometallic complex represented by IL (II), (IV), or (VI).

(In the formula, X and X' are a group selected from hydrogen, an alkyl group, a substituted alkyl group, a halogen group, and a nitro group.

n and m are integers from 1 to 4, 1M is nickel, cobalt,
Indicates palladium or platinum. ) (In the formula, Y, Y', Y" and Y'" are hydrogen and an alkyl group.

The group 1M is selected from phenyl group and cyano group.

Indicates a metal selected from nickel, cobalt, palladium and platinum. ) (In the formula, Z and Z' are hydrogen, an alkyl group, and a halogen group, and the group 9M is nickel or cobalt.

A metal selected from palladium and platinum, n is an integer of 1 to 4, II is an integer of -1 or -2, A is a monovalent cation when l is -1, and l! When is -2, it indicates a divalent cation. ) (wherein E and E' are hydrogen, an alkyl group, a phenyl group, an alkyl group, an alkoxy group, a halogen-substituted phenyl group, and a chenyl group; p is an integer of 2 or 3; 9M is an integer of 2 or 3; Time is a nickel.

A group selected from cobalt, palladium and platinum.

When p is 3, it represents a metal selected from vanadium, chromium and molybdenum. ) (Formula fV), in ('4), G and G' are hydrogen, an alkyl group, and a halogen group, and group 9M is nickel.

A metal selected from cobalt, palladium and platinum.

m is an integer of -1 or -2, and A is when m is -1.

It is a monovalent cation, and when 1m is -2, it indicates a divalent cation. ) The organometallic complex that is the near-infrared absorbing dye used in the present invention is, for example, G.N.
Journal of the American Chemical Society (Journal of the American Chemical Society)
nal of the American Chemi
calSociety) Volume 87 (1965) 5585
~5592 pages, M.J. Baker Hawks (M
, J. Baker-Hawkes, E. Billig, Barry B.
Gray (HarryB, Gray)'s journal
Of the American Chemica%-Sonaete 4 (Jo
Urnal of the American Chem
ical 5ociety) Volume 88 (1966) 48
pp. 70-4875, N.L.Ba
1ch)'s Journal of the American Society 4- (Journal of the American Society) A recording film made of an organometallic complex represented by the above general formula (symbol) and nitrocellulose is irradiated with semiconductor laser light, and due to the heat of the laser, , a method of chemically decomposing organometallic complexes using the strong oxidizing action of nitrocellulose
16888) and a method in which 10 is evaporated by heat generated by laser irradiation and the spot is recorded as a transparent dot (Japanese Patent Laid-Open No. 11090/1983), but none of these methods have been reported. Pumping is also a heat mode, and in the latter case, the evaporation of (IIl) requires kana p energy to master the evaporation, so the sensitivity is low, and in the former case, the latter In the case of , jl also has high sensitivity, but there seems to be a problem with thermal storage stability.

In the optical recording medium of the present invention, a near-infrared absorbing dye having absorption in the oscillation wavelength region of a semiconductor laser and an initiator or an initiator system that generates radicals by actinic rays are allowed to coexist completely, and the initiator or initiator Recording is performed by dividing the organometallic complex by decomposing it with radicals generated from the system, or by transferring energy absorbed by the initiator or initiator system to the organometallic complex. . According to the optical recording medium of the present invention, recording is performed by the disappearance of absorption due to the decomposition of the organometallic complex.
The generation of noise due to shape changes is suppressed, and the sensitivity is high compared to conventional systems using organometallic alone because energy does not evaporate outside the system. There is no risk that the stability will be impaired due to thermal factors during storage, as in the case of the present invention.

In the present invention, the above general formula (17(1111 □□□
An organometallic complex represented by (V) or (■) is used.

Examples of the aromatic diamine metal complex represented by the general formula tl) include bis(4-chloro-〇-phenylenediamino)nickel (λmax 800 nm, ε66600
), bis(4-methyl-O-phenylenediaminononincle (λmax 795 nm.

ε55100) and so on. As the aliphatic diamine metal complex represented by the general formula +[), for example, bis(diiminosuccinonitri0)nickel (λmax 7
00 nm, t 25500 ) bis(diiminosuccinonitrilo)palladium (λmax 705 nm
, ε8500).

Examples of the aromatic dithiol-based metal complex represented by the general formula (111) include bis(1-methyl-5°4-dithioferrate)nickel (El)tetra-n-butylammonium (λmax890 nm).

ε16270), bis(1,2,3,4-tetrachloro-5,6-sithioferto)nickel(II)tetra-n-butylammonium (λmax885nm,
ε75700).

An aliphatic dithiol metal complex represented by the general formula (M) and 1
~, for example, bis[cis-1,2-bis(p-methoxyphenyl)ethylene-1,2-diteolate]nickel (λmax 920 nm.

ε35000), bis(cis-1,2-hisphenylethylene-1,2-cyteole-),)platinum(λmax
800 nm, c 5 + 6 Q Q ), tris(cis-1,2-hisphenylethylene-1,2-thiolate) palladium (λmax 750 nm,
ε27000).

General formula (■ or (■) mercaptophemerkabuto-2-5t7trate) nickel full, ltestra-n-butylammonium (λmax i 1QO
nm, ε12290), bis(1-mercapto-2
-ferulate) nickel(II) tetra-n-butylammonium (λmax+025nm.

ε12700).

The above general formula (11, (1), (■l, (IVI, tV
) or (■ The organometallic complex shown alone or -j
The upper parts are used in combination.

In the present invention, an organic polymeric binder may be used, and in this case, various natural organic polymeric compounds and organic polymeric compounds having film-forming ability can be used. Examples of the former include gelatin, cellulose derivatives,
Examples include dextran, rosin, and rubber. Examples of the latter include hydrocarbon resins such as polyethylene, polypropylene, polystyrene, and polyimbutylene, vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride-polyvinyl acetate copolymers, and polyacrylic acid. Synthetic resins include acrylic resins such as methyl and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resins, butyral resins, rubber derivatives, and thermosetting initial condensates such as phenol-formaldehyde resins.

Preferred examples of initiators or initiator systems that generate radicals by actinic rays in combination with organometallic complexes include (Tl Norrish Type I) penzoin isoglopylether of benzoin alkyl ethers, ketals that perform type I cleavage; α,α-dimethoxyα-
Phenylacetophenone, α,α-dimethoxy-acetophenone, 2-hydroxy-2-methylpropionphenone, 4'-isopropyl-2-hydroxy-2-methylpropionphenone, etc. (2) Oxime esters such as 1-phenyl- 1,2
-furopandione-2-0-benzoyloxime, 1-
7enyl-1.2-7'ropanedione-2-(0-ethoxycarbonyl)ogisime, etc. (3) 2-ethylanthraquinone, which is a single hydrogen abstraction type, and a dual hydrogen abstraction type, which is an aromatic carbonylated adduct and an amine. Examples of aromatization adducts include benzophenone and its derivatives, thioxanthone and its derivatives, etc.; examples of amines include triethanolamine, ethyl-4-dimethylaminobenzoate, 2-(dimethylamino)ethylbenzoate, isobentyldimethylaminobenzoate, 4
．． (4) In the system of imidazole dimer and visible light sensitizer, imidazole dimers include hexaphenylbis-imidazole and its derivatives, visible light sensitizers include eosin, Quinanthene dyes such as erythrosine, thiazine dyes such as methylene blue and theonine, porphyrins such as hematoporphyrin and zinc tetraphenylporphyrin, biryllium salts, thiapyrylium salts, selenapyrylium salts, cyanine dyes merocyanine dyes, aromatic conjugated ketones, acyl Group-substituted coumarins, acridine derivatives, etc. (5) Examples of organic peroxides in the system of organic peroxides and polycyclic aromatic adducts include tert-butyl peroxide,
Polycyclic aromatic compounds such as benzoyl peroxide include naphthalene, pyrene, anthracene, fluorenone, etc. (6) a system of the organic peroxide and the visible light sensitizer, (7) an acyl oxime and the visible light Examples of acyloximes in the sensitizer system include linear 0-acyloximes such as 0-benzylbiacetylmonoxime, and cyclic acyloximes such as 6-phenyl-5-ynoxacilone. Visible light sensitizer thread...Rogenated compounds include carbon tetrabromide, tripromometerbenzenesulfoun-1-,2,4,6-tris(trichloromethyl)-1,5,5- Triazine, anthraquinone-1-sulfonyl chloride, etc. (9) Thiol compounds in the system of a thiol compound and the visible light sensitizer include 2-mercaptobenzoxazole,
Examples include heterocyclic thiols such as 2-mercaptobenzimidazole and 2-mercaptobenzothiazole.

Two or more of these may be used within the above group or across one group and other groups, if necessary.

The organometallic complex of the present invention is usually used in the form of a film or sheet by kneading it into a dispersion medium such as a transparent plastic, or it is dissolved in a solvent, or it can be used as an organic polymer binder having film-forming ability. For use, the mixture is mixed and applied to a base material that becomes a support. In this case, various butylene additives such as plasticizers such as tricresyl phosphate, dibutyl phthalate, and dioctyl phthalate, and antioxidants such as phenols, aminos, and hydroxylamines can be added as required.

The addition ratio of the organometallic complex to the organic polymer binder is
The addition ratio is 1 to 50% by weight, and the addition ratio to the optical monometal complex may be 1 mol% or more, but it is preferable to add the amount within a range that does not increase the probability of the generated radicals re-crystallizing by more than 9%.

A mercury lamp, a high-pressure water laser, a helium-neon laser, or the like is used as a source of active light.

Examples of solvents for dissolving the organometallic complex and organic polymer binder include ketone solvents such as acetone and methyl ethyl ketone, alcohol solvents such as ethanol and isopropanol, cellosolve solvents such as methyl cellosolve and ethyl cellosolve, and ethylene glycol. These include glycol ether ester solvents such as monomethyl ether and diethylene glycol monomethyl ether acetate, chlorinated hydrocarbon solvents such as dichloromethane, chloroform, and trichloroethane, hydrocarbon solvents such as benzene and toluene, dimethylformamide, and dimethyl sulfoxide. It is possible to use any one or more of these solvents.

Examples of the substrate on which the entire recording medium is coated include polyethylene terephthalate, polycarbonate tonoblast film, glass, etc., which are transparent to laser light and have heat resistance.

For reading, various semiconductor lasers corresponding to the near-infrared absorption of the organometallic complex can be used, but it is particularly preferable to use a semiconductor laser whose absorption wavelength is close to the thickest wavelength of the organometallic complex.

In the optical recording medium of the present invention, a protective film may be entirely formed by a conventional method for the purpose of protecting the recording layer. In this case, it is particularly desirable that the protective film has a high oxygen barrier property. this is.

This is because oxygen, as a radical scavenger, tends to reduce the sensitivity of the optical recording medium of the present invention.

The protective film material to be used may be thermally and optically stable, and for example, the organic polymer binder mentioned above may be used as is. These are in film or sheet form 2! f'' may be applied, or may be formed by a coating method.

In the optical recording medium of the present invention, if necessary,
A reflective layer may also be provided. The reflective nozzle can be provided between the substrate and the recording layer, or on the opposite surface of the recording layer. Providing the reflective layer improves the ratio when reading by reflected light. At this time, the reflective layer
It is also possible to serve as the above-mentioned protective film. The reflective layer used is preferably a 1% metal vapor-deposited film, and examples include metals such as aluminum, copper, gold, nickel, and chromium. These may be formed by vacuum deposition, and the purpose can also be easily achieved by chemical plating.

The optical recording medium according to the present invention can be used for optical discs, display elements, etc.

(Example) The present invention will be specifically explained below with reference to Examples. Parts are by weight.

15 ml of the 4.9 x 10-' mol/l benzene solution of Example 1 (manufactured by Geigy) was mixed in an equimolar amount with (1), placed in a quartz glass test tube, and irradiated with a high-pressure mercury lamp. The change in absorbance of the organometallic complex near 850 m1D was investigated, and the results are shown as curve A in FIG. As a comparative example, the same test was conducted without adding an initiator, and the results are shown as curve B in FIG.

When the same procedure was performed using methylene chloride as the solvent, changing the quartz glass test tube to a Pyrex test tube, and adding 5 times the mole of initiator, the same results as when using complex (1) were obtained. I did 7.

When the solvent was changed to dimethylformamide and the open '913 agent was changed to 6 times the molar amount using a Pyrex test tube, similar results were obtained as when using the complex (υ).

When the solvent was changed to methylene chloride and the initiator was changed to 5 times the molar amount using a Pyrex test tube, the same results were obtained as when complex (1) was used.
child.

Example 2 Using the complex (1) of Example 1, initiator i1rUgaCu
In place of re651, 2-ethyl anthraquinone was used in the same manner as in Example 1 (track Hc in Figure 2), and the initiator 2,4-diethylthioxanthone (DETX) and impentele-4-dimethylaminobenzoate (DMB
The same procedure was carried out using the binary initiator I) (curve D in Figure 2).

FIG. 2 also shows B in FIG. 1 for comparison.

Example 5 Using the complex (1) of Example 1, initiator i 3.5'-carbonylbis[7-diethylaminocoumarin] and N-methylphenylglycine (NMPG) [molar ratio i: 7
C1) combination, riboflavin tetrabutyrate (
When the same procedure was carried out using a combination of RFTB ) and DMB 1 (molar ratio 1:6), the results shown in FIG. 5 were obtained (seven curves E and F). When the same procedure was carried out by replacing complex (4) with complex (4), the same results as in the case of using complex (1) were obtained.For complex (2) or (6), initiator '1RFTB and DMB I When the same combination was carried out, similar results were obtained as when complex (1) was used.

Example 4 Complex (2) contains 5 times the molar amount of erythrosin B,! : formula t
The imidazole dimer F shown in 5) was mixed with all benzene as a solvent, and acetonyl (volume ratio 1:1) was added to a Xe lamp through a Toshiba colored glass filter Y-48 and a Toshiba colored glass filter 5O5. When visible light was irradiated, the results shown in Figure 4 were obtained. rI-1 (song BAH).

As a comparative example, the same procedure was carried out without adding the above initiator system, and the results are shown as curve G.

Furthermore, when the same procedure was carried out using complex (1) instead of complex (2), the same results as when complex (2) was used were obtained.

implementation? 115 Using the complex (1) of Example 4, the initiator system was a combination of methylene blue and one imidazole compound shown in formula (5) of Example 4, and the mixture was passed through a Corning 2-73 filter to a Xe lamp. The same applies to cases where shipbuilding is not carried out.
(curve J).

Example 6 Complex (410.05 parts, 1 part of polymethyl methacrylate and 0.4 parts of IrUgaCure 65 + 0.4 parts) was dissolved in 5 parts of total methyl ethyl ketone and spin coated onto a glass plate. This was dried for 10 minutes at 60°C and recorded. When irradiated with an ultra-high pressure mercury lamp, the results shown in FIG. 6 were obtained (song UnK).

As a comparative example, the same procedure was carried out for 5-8- without adding an initiator (curve L).

When the same procedure was carried out using complex (1) instead of complex (4) and using 1°t 2-trichloroethane as the solvent, the same results as in the case of complex (4) were obtained.

Example 7 On the recording layer obtained using the complex (4) of Example 6, a polyvinyl alcohol aqueous solution was further applied by lath spin coating.
It was dried at 00°C for 10 minutes to form a protective layer. The same procedure as in Example 6 was carried out on this recording medium, and the results were as follows.
The results shown in FIG. 7 were obtained (song HM). As a comparative example, the same procedure was carried out in the case where no protective film was formed (track a).
N).

As shown in Figures 1 to 7, by using a near-infrared absorbing dye that absorbs in the oscillation wavelength region of a semiconductor laser and an initiator or initiator system that generates radicals by actinic rays, the conventional near-infrared absorbing Recording sensitivity is improved compared to when only dye is used.

(Effects of the Invention According to the present invention, the sensitivity of the recording medium made of only the organic gold J!4 complex is the same as above.

[Brief explanation of drawings]

FIGS. 1 to 7 are graphs showing changes in absorbance or permeability of the compositions shown in Example flJ.

Claims (1)

[Claims] 1. An optical recording medium containing a near-infrared absorbing dye having absorption in the oscillation wavelength region of a semiconductor laser and an initiator or initiator system that generates radicals by actinic rays,
The near-infrared absorbing dye has the following general formula (I), (II), (
An optical recording medium containing one or more of the organometallic complexes represented by III), (IV), (V), or (VI). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, X and X' are groups selected from hydrogen, alkyl groups, substituted alkyl groups, halogen groups, and nitro groups, n and m
represents an integer of 1 to 4, and M represents nickel, cobalt, palladium or platinum. ) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, Y, Y', Y'' and Y''' are groups selected from hydrogen, alkyl groups, phenyl groups and cyano groups, M is nickel, Indicates a metal selected from cobalt, palladium, and platinum.) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ (III) (In the formula, Z and Z' are groups selected from hydrogen, alkyl groups, and halogen groups, and M is A metal selected from nickel, cobalt, palladium and platinum, n is an integer of 1 to 4, l is an integer of -1 or -2, A is a monovalent cation when l is -1, and l -2 indicates a divalent cation.) ▲Mathematical formulas, chemical formulas, tables, etc.▼(IV) (In the formula, E and E' are hydrogen, an alkyl group, a phenyl group,
A group selected from an alkyl group, an alkoxy group, a halogen-substituted phenyl group, and a chenyl group, p is an integer of 2 or 3, M
When p is 2, metal selected from nickel, cobalt, palladium and platinum; when p is 3, vanadium;
Indicates a metal selected from chromium and molybdenum. ) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(V) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(VI) (In formulas (V) and (VI), G and G' are hydrogen, alkyl groups, and halogen groups M is a metal selected from nickel, cobalt, palladium and platinum, m is -1
Alternatively, A is an integer of -2, when m is -1, it is a monovalent cation, and when m is -2, it is a divalent cation. ) 2. The initiator or initiator system that generates radicals by actinic rays is (1) benzoin alkyl ethers or ketals that perform Norrish Type 1 cleavage, (2) oxime esters, (3) single hydrogen abstraction type or aromatic carbonyl. Binary hydrogen abstraction type of compound and amine (4) System of imidazole dimer and visible light sensitizer (5) System of organic peroxide and polycyclic aromatic compound (6) Organic peroxide and visible light A patent selected from photosensitizer system (7) system of acyl oxime and visible light sensitizer, (8) system of halogen compound and visible light sensitizer, and (9) system of thiol compound and visible light sensitizer. An optical recording medium according to claim 1.