JPH0558914B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to an optical information recording medium having a recording layer containing a compound in which a cyanine dye and a transition metal complex are combined. [Prior Art] Conventionally, an information recording and reproducing apparatus is known that records and reproduces information by irradiating a rotating disk-shaped information recording medium with a laser beam. As a recording layer of an information recording medium used in this type of information recording device, a recording layer using a low melting point metal or a low melting point metal and a dielectric material has been proposed. However, these have drawbacks such as poor storage stability, low resolution, low recording density, and high cost. As a result of various studies, the inventors of the present invention found that when a cyanine dye is used in the recording layer, a recording medium with a high writing sensitivity and reflectance and a high reading S/N ratio can be obtained, and has already proposed this method. ing. However, when the above-mentioned dyes are used, there is a problem that the storage stability of the recording medium against light, the storage stability after recording, and the storage stability against repeated irradiation with readout light after recording, that is, storage against reproduction light, are insufficient. [Purpose] The present invention has been made in view of the above problems, and its main purpose is to provide an optical information recording layer having a recording layer containing a cyanine dye, which prevents deterioration against reproduction light and has improved storage stability against light. The goal is to provide a medium. [Structure] As a result of conducting various studies to achieve the above object, the present inventors found that a cyanine dye and a transition metal complex are bonded to a recording layer of an optical information recording medium through a methylene group, which is represented by the following formula []. The present inventors have found that by incorporating a compound, the storage stability against reproduction light and the storage stability against light can be significantly improved, leading to the completion of the present invention. formula〔〕 However, in the above formula [], φ and ψ may be the same or different and each represents an indole ring residue or a benzoindole ring residue, and L is monocarbocyanine, dicarbocyanine, tricarbocyanine, or tetracarbocyanine. represents a linking group for forming cyanine, X ^- represents an anion, m is an integer of 0 or 1,
T represents a transition metal complex, L and T are linked to a methylene group in such a way that each hydrogen atom is replaced, and n is an integer from 1 to 12. That is, the optical information recording medium of the present invention has, on a substrate, a recording layer containing a compound represented by the above formula [], which is formed by bonding a cyanine dye and a transition metal complex with a methylene group. Next, each of φ, ψ, L, and T in the above formula [] will be explained in detail. φ and ψ represent indole ring or benzindole ring residues, and various substituents may be further bonded to this ring. φ is N of the indole nucleus
The atoms have a + charge and ψ has a neutral N atom. Moreover, it is preferable that φ and ψ are the same, and it is particularly preferable that they are represented by the following formulas [] to []. In this case, the charge symbol (・) attached to the 2nd position of the indole ring is

[Formula] ψ

[Formula]. formula〔〕 formula〔〕 formula〔〕 formula〔〕 However, in the above formulas [] to [], R ₁
represents a substituted or unsubstituted alkyl group. The alkyl group preferably has 1 to 5 carbon atoms, and preferable substituents include a sulfonic acid group and an alkylcarboxyoxy group. Other substituents include alkylamido groups, alkyloxy groups, carboxylic acid groups,
It may also be a hydroxyl group. Note that R ₁ may be a substituted or unsubstituted aryl group. In such a case, when m is 0 (described later), φ is
R ₁ has a negative charge. Further, R ₂ and R ₃ each represent an alkyl group or an aryl group such as a phenyl group, preferably an alkyl group. In this case, the alkyl group is unsubstituted and preferably has 1 or 2 carbon atoms, especially 1 carbon atom. Furthermore, R ₄ includes an alkyl group, an aryl group, a heterocyclic residue, a halogen atom, an alkoxy group,
Examples include an alkylthio group, an alkylhydroxycarbonyl group, and a carboxylic acid group. And p is usually an integer from 0 to 4, and p is 2
In the above case, the plurality of R ₄ may be different from each other.
However, if there is no particular need, p may be 0. On the other hand, L represents a linking group for forming mono-, di-, tri- or tetracarbocyanine,
In particular, any one of the following formulas [] to [XII] is preferred. formula〔〕 formula〔〕 formula〔〕 formula〔〕 formula〔〕 Formula [XI] Formula [XII] However, in the above formula, Y represents a hydrogen atom or a monovalent group. In this case, monovalent groups include lower alkyl groups such as methyl groups, lower alkoxy groups such as methoxy groups, dimethylamino groups, diphenylamino groups, methylphenylamino groups, morpholino groups, imidazolidine groups, ethoxycarbonylpiperazine groups, etc. Preferable examples include a di-substituted amino group, an alkylcarbonyloxy group such as an acetoxy group, an alkylthio group such as a methylthio group, a halogen atom such as Br and Cl, a cyano group, and a nitro group. In addition, among these formulas [] to [XII], tri- or tetracarbocyanine formulas [] to
[] Particularly preferred are formulas [] and [XII]. Furthermore, X ^- is an anion, preferred examples of which are I ^- , Br ^- , ClO ₄ ^- , BF ₄ ^- ,

[Formula] Examples include alkyl sulfate ions. Note that m is 0 or 1, but when m is 0, R ₁ of φ usually has one charge and becomes an inner salt. Next, T represents a transition metal chelate compound,
It is connected to the above L through a methylene group (CH ₂ ) _o (n is an integer from 1 to 12) in such a manner that each hydrogen atom is substituted. In formula [], the cyanine dye part φ-L=ψ mainly plays the role of a light-absorbing dye, whereas the transition chelate compound part T mainly plays the role of preventing deterioration due to reproduction light and acting as a light-absorbing dye. It is thought that this plays a role in improving the shelf life of the raw material. From this point of view, the compound of formula [] is a single compound that simultaneously functions as a light-absorbing dye and as a stabilizer against light and reproduction light. In the case of this transition metal chelate compound, the central metals include Ni, Co,
Cu, Mn, Pd, Rt, etc. are preferred, and the following compounds are particularly preferred. In addition, as a transition metal chelate compound, 700
Those with absorption at ~1500 nm, especially 700 nm
It is preferable that it has a maximum absorption wavelength of ~1200 nm. 1 Bisdithio-α-diketone system However, R(1) to R(4) represent a substituted or unsubstituted alkyl group or aryl group, and M is Ni,
Represents transition metal atoms such as Co, Cu, Pd, and Pt.
In this case, M has a negative charge and may form a salt with a cation such as a quaternary ammonium ion. Specific examples of this compound are shown below. T ₁ Ni[]dithiobenzyl T ₂ Ni[]dithiobiacetyl T _{3 T4 T5} 2 Bisphenyl dithiol type However, R(5) and R(6) are alkyl groups such as methyl groups, or halogen atoms such as Cl, or
Represents an amino group such as N(CH ₃ ) ₂ or NH ₂ ,
M represents a transition metal atom such as Ni, Co, Cu, Pd, or Pt. Furthermore, a and b are each 0 or an integer of 4 or less. Also, M in the above structure is −
May be charged and form salts with cations,
Further, other ligands may be bonded above and below M. Specific examples of this compound are shown below. T ₆ PA-1001 (Product name: Mitsui Toatsu Fine Co., Ltd.) T ₇ PA-1002 [Same as above Ni-bis(toluenedithiol)tetra(t-butyl) ammonium] T ₈ PA-1003 (Same as above) T ₉ PA- 1005 [Same as above Ni-bis(dichlorobenzene)tetra(t-butyl)ammonium] T ₁₀ PA-1006 [Same as above Ni-bis(trichlorobenzenedithiol)tetra(t-butyl)ammonium] T ₁₁ Co-bis(benzene-1 ,2-dithiol)tetrabutylammonium T ₁₂ Co-bis(o-xylene-4,5-dithiol)tetra(t-butyl)ammonium T ₁ Ni-bis(benzene-1,2-dithiol)
Tetrabutylammonium T ₁₄ Ni-bis(o-xylene-4,5-dithiol) Tetrabutylammonium T ₁₅ Ni-bis(5-chlorobenzene-1,2-
dithiol)tetrabutylammonium T ₁₆ Ni-bis(3,4,5,6-tetramethylbenzene-1,2-dithiol)tetrabutylammonium T ₁₇ Ni-bis(3,4,5,6-tetrachlorobenzene-1 ,2-dithiol)tetrabutylammonium T ₁₈ 3 Salicylaldehyde oxime series However, R(7) and R(8) represent an alkyl group, and M represents a transition metal atom such as Ni, Co, Cu, Pd, or Pt. Specific examples of this compound are shown below. T ₁₉ Ni[]O-(N-isopropylformimidoyl)phenol T ₂₀ Ni[]O-(N-dodemylformimidoyl)phenol T ₂₁ Co[]O-(N-dodecylformimidoyl)phenol T ₂₂ Cu[]O-(N-dodecylformimidoyl)phenol T ₂₃ Ni[]2,2'-[ethylenebis(nitrilomethylidine)]-diphenol T ₂₄ Co[]2,2'-[ethylenebis( Nitrilomethylidine)]-diphenol T ₂₅ Ni[]2,2'-[1,8-naphthylenebis(nitrilomethylidine)]-diphenol T ₂₆ Ni[]-[N-phenylformamidoyl]
Phenol T ₂₇ Co〔〕−〔N-phenylformimidoyl〕
Phenol T ₂₈ Cu [] [N-phenylformimidoyl]
Phenol T ₂₉ Ni[]Salicylaldehyde Phenylhydrazone T ₃₀ Ni[]Salicylaldehyde Oxime 4 Oxime series However, R(9) and R(10) represent an alkyl group such as a methyl group, and M represents a divalent transition metal atom such as Ni or Pd. Further, coordination may be performed above and below M in the above structure. Specific examples of this compound are shown in the table below.

[Table] 5 Thiobisphenolate chelate system However, M is the same as above, R(11) and
R(12) represents an alkyl group. Further, M has a negative charge and may form a salt with a cation. Specific examples of this compound are shown below. T ₃₄ Ni[]n-butylamino[2,2'-thiobis(4-tert-octyl)-phenolate]
[Cyasorb-UV-1084 (American Cyanamide Co., Ltd.)] T ₃₅ Co [] n-butylamino [2,2'-thiobis(4-tert-octyl)-phenolate] T ₃₉ Ni []-2, 2'-Thiobis(4-tert-octyl)-phenolate Next, specific examples of the main elements constituting the compound of formula [] of the present invention are shown in Table 1 below. It is not limited.

【table】

[Synthesis example]

An example of synthesis of the compound DT ₁ will be explained according to the following reaction formula. Synthesis example 1 [] Phosphorane 2 obtained from 2-(bromomethyl)-1,3-dioxolane and triphenylphosphine
When the Wittig reaction is performed between and aldehydes,
Vinylogous α,β-unsaturated aldehydes can be obtained. Utilizing this reaction, dibromobenzaldehyde is converted into compounds 3 to 3 in two steps. 1
Yield about 55% in stages. Next, hydrogen was added to Compound 3- in the presence of a Ni catalyst to obtain Compound 4-. Furthermore, compounds 4~ are treated with Grignard reagent CH ₃ MgX
The product was hydrolyzed to give secondary alcohol 5~, and this compound 5~ was oxidized to give the target compound 1~. [] Compounds 1 to 1 obtained in the above [] and two equivalents of copper thiobutyrate were reacted in quinoline at 200°C for 7 hours. The product was further reacted with sodium in liquid ammonia to give compounds 7-. In a similar manner, benzene 1,2-dithiolate 8~
I got it. Potassium metal was added to absolute ethanol to generate potassium ethoxide, and equimolar amounts of compounds 7~ and 8~ were added. Furthermore, an equimolar amount of an ethanol solution of nickel chloride was added to 7~ and 8~. Furthermore, after adding tetrabutylammonium chloride, the reaction solution was cooled and the precipitate was filtered. The obtained product was separated by column chromatography to obtain the desired product 6-. [] After triphenylphosphorane 10~ was obtained by reacting the corresponding phosphonium salt with butyllithium in tetrahydrofuran (THF), the above compound 6~ was obtained.
A TEF solution was added dropwise, and the mixture was stirred at room temperature for 6 hours. The product obtained from this Wittig reaction was extracted and recrystallized from chloroform-methanol to obtain compounds 9-.
Yield 85%. [] Synthesis of (compound DT ₁ ) Compound 9 ~ (1 mol), 1-ethyl-2-(β-acetanilide vinyl)-3,3-dimethylindolium perchlorate, i.e. compound 11 ~ (1.1 mol)
and triethylamine (2 mol, 0.5 ml) were dissolved in 10 ml of ethanol and refluxed for 15 minutes. The reaction mixture was left overnight and filtered, then washed with water and ethanol and dried to obtain the desired compound _DT1 . Recrystallization was performed twice with methanol. Yield 60. Synthesis Example 2 Compound DT ₁ was synthesized by replacing the procedures of step [] and step [] in Synthesis Example 1 above.
The reaction route in this case is as follows. [′] [″] Incidentally, other compounds of the formula [] according to the present invention can also be synthesized in the same manner as described in Synthesis Examples 1 and 2 above. [Example] The present invention will be further explained with reference to Examples below, but the present invention is not limited thereto. Example 1 A 1.4% by weight 2,2'-dichloroethane solution of Compound Example DT ₁ was prepared, and this solution was applied onto a glass substrate and dried to form a recording layer with a thickness of 600 Å, thereby producing a recording medium. This recording medium was irradiated with light of 54,000 lux using a 500 watt tungsten lamp, and then the rate of decrease in the absorption peak of the dye was measured. DT ₁
When compared with the case of using only the cyanine dye (Japanese Photosensitive Dyes NK125) having the φ-L=ψ part, that is, the following structural formula, the rate of decrease was 0.2 in relative value.
Furthermore, when we checked the stability of the same recording medium against reproduction light, we found that the above cyanine dye
It is more than 10 times improved than that of NK125. Examples 2 to 25 Each recording medium was produced in the same manner as in Example 1, except that the compound of the formula [] shown in Table 2 below was used instead of the compound in Example 1. Table 2 below shows the results of measuring the absorption peak reduction rate and stability against reproduction light for each recording medium. The absorption peak reduction rate is expressed as a relative value with the cyanine dye (NK125) described in Example 1 as 1.

【table】

〔effect〕

According to the optical information recording medium of the present invention, it is possible to increase the number of readouts after recording, that is, to prevent deterioration due to reproduction light, to improve storage stability against light, to simplify the manufacturing process, and to reduce costs.

[Brief explanation of drawings]

1 to 4 are cross-sectional views showing the structure of the optical information recording medium of the present invention. 1... Substrate, 2... Recording layer, 3... Undercoat layer,
4...Protective layer.

Claims (1)

[Scope of Claims] 1. An optical information recording medium characterized by having, on a substrate, a recording layer containing a compound represented by the following formula [], which is formed by bonding a cyanine dye and a transition metal complex with a methylene group. . formula〔〕 [However, φ and ψ may be the same or different and each represents an indole ring residue or a benzoindole ring residue, and L forms monocarbocyanine, dicarbocyanine, tricarbocyanine, or tetracarbocyanine. represents a linking group for , X ^- represents an anion, m is 0
or an integer of 1, T represents a transition metal complex, L and T are connected to the methylene group in such a manner that each hydrogen atom is substituted, and n is an integer of 1 to 12].