JPS63299989A - Optical data recording medium - Google Patents

Abstract

PURPOSE:To contrive higher stability to reproducing light, higher thermal stability and higher sensitivity, by providing an organic thin film comprising a compound of a specified formula. CONSTITUTION:An organic thin film recording layer 2 comprising a compound of formula (I) as a main constituent is provided on a substrate 1. In formula (I), each of R<1> and R<2> is hydrogen or a lower alkyl, Ar is a substd. or unsubstd. aromatic ring, X is an anion, m is an integer of 1 or 2, and A is formula (II). Examples of R<1> and R<2> include hydrogen, methyl, ethyl, propyl, isopropyl, n- butyl, isobutyl, tert-butyl and hexyl. The aromatic ring Ar may be phenyl nucleus, naphthyl nucleus, thiophene nucleus, pyridine nucleus or the like, and a substituent on such a nucleus may be an alkyl such as methyl, ethyl and propyl; an alkoxyl such as methoxyl and ethoxyl; a halogen such as fluorine and chlorine; hydroxyl, or the like.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to an optical information recording medium, and specifically relates to an optical information recording medium.

The present invention relates to an optical information recording medium suitable for writing, recording, and reproducing using laser light.

[Prior art]

2. Description of the Related Art Information recording and reproducing apparatuses that record and reproduce information by irradiating a rotating disk-shaped optical information recording medium with laser light are known and are in practical use. As optical information recording media used in this type of information recording apparatus, there are also known optical information recording media that are composed of a substrate, a metal reflective film, and a translucent colored layer containing a dye.

In such a recording medium, laser light incident on a semi-transparent colored layer containing a dye reaches a metal reflective film and is reflected so that the reflected light can be easily detected.In this case, the metal reflective film is colored. This layer is provided to compensate for the amount of reflected light that is insufficient with just the layer. However, the presence of the metal reflective film complicates the structure of the optical information recording medium and causes an increase in cost.

Therefore, it has been proposed to eliminate the above-mentioned drawbacks by using an organic dye monolayer film with high reflectance and bronze luster. In particular, when a cyanine dye with high light absorption is used as the recording film (recording layer), a light absorption/reflection film exhibiting metallic luster (reflectance of 20 to 30%) can be obtained with a film thickness of 300 to 600%.
Recording and reflective reading using laser light become possible. In addition, when a semiconductor laser with a wavelength of 750 to 850 nm is used as a laser light source, there is an advantage that the device can be made smaller. However, organic dyes are generally not necessarily stable against light and heat, and the reality is that there is a demand for the development of new organic thin films that have satisfactory properties.

〔the purpose〕

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an optical information recording medium that has excellent stability against reproduction light and thermal stability, and is highly sensitive.

[Structure] The optical information recording medium of the present invention has the following general formula (I) [wherein R", R": hydrogen atom or lower alkyl group, Ar: substituted or unsubstituted aromatic ring, X: anion m : an integer of 1 or 2;

Incidentally, the present inventors have discovered that the compound represented by the general formula (I) is useful as a stable optical information recording material, and that this compound can be used in other organic dye recording materials (especially cyanine dyes and merocyanine dyes). ) It has been confirmed that the stability of the optical information recording medium becomes even better when used in combination with the above.The present invention has been made based on this.

The invention will be explained in more detail below with reference to the accompanying drawings.

FIG. 1 shows a type of light in which an organic thin film recording layer (hereinafter sometimes abbreviated as "recording layer") 2 containing a compound represented by the general formula (I) as a main component is provided on a substrate 1. It is an information recording medium. Fig. 2 shows an optical information recording medium in which a subbing layer 3 is provided between the substrate 1 and the recording layer 2, and Fig. 3 shows an optical information recording medium shown in Fig. 1, but in which a protective layer 4 is provided on the recording layer 2. recoding media,
FIG. 4 shows an optical information recording medium shown in FIG. 2, in which a protective layer 4 is provided on the recording layer 2. As mentioned above, the recording layer 2 in the present invention is an organic thin film containing the compound represented by the general formula (I).

In the general formula (I), specific examples of RL and R1 include hydrogen, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, 1so-butyl group, tert-butyl group, hexyl group, etc. .

The aromatic rings of Ar include phenyl, naphthyl, thiophene, and pyridine nuclei, and substituents for these nuclei include alkyl groups such as methyl, ethyl, and propyl groups; alkoxy groups such as methoxy and ethoxy groups; Groups; halogen atoms such as fluorine and chlorine; hydroxyl groups, etc.

Examples of the anion of Examples include acid ions, sulfate ions, chloride ions, bromide ions, and iodide ions.

These compounds represented by general formula (I) are prepared by dissolving raw materials represented by (Ar is the same as above) in a solvent such as acetone, diethyl ether, dimethyl sulfonate, etc.
It can be easily synthesized by reacting silver hexafluoroantimonate or silver perchlorate.

Typical specific examples of the compound represented by the general formula (I) are as follows.

As mentioned above, the recording layer 2 in the present invention may be formed solely of the compound represented by the general formula (I) that has the ability to absorb the wavelength of the laser beam used;
If the compound I) is used in combination with a cyanine dye and/or a merocyanine dye, an even better optical information recording medium can be obtained. Here, the mode of "combining" the cyanine dye and/or merocyanine dye with the compound of general formula (I) is when the cyanine dye and/or merocyanine dye is present in the recording layer 2 together with the compound of general formula (I). In addition, it also includes a case where a cyanine dye and/or a merocyanine dye is added to the undercoat layer 3, the protective layer 4, etc. Any cyanine dye and merocyanine dye can be used, and representative examples thereof include compounds represented by the following general formulas (n-1) and (II-2), respectively.

(However, R3 and R4 may be the same or different, and each represents an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group, an aralkyl group, a carboxyalkyl group, a carboxyalkylate group bonded to an alkali metal cation, a sulfoalkyl group) Zl and z2 can form a 5- or 6-membered heterocycle or a fused ring containing a 5- or 6-membered heterocycle. Represents an atomic group.Q is 1 to 4
represents an integer, and xo represents an anion. ) The substrate 1 must be transparent to the laser beam used when writing and recording is performed from the substrate side, and does not need to be transparent when writing and recording from the recording side.The substrate may be glass, polycarbonate, or polymethyl. Although methacrylate (methacrylate) is usually used, any other material used in recording media may be used.

Regarding the undercoat layer 3 and the protective layer 4 provided as necessary on the organic dye thin film B layer 2 in the present invention, the undercoat layer 3 is used to (i) improve adhesion, (ii) provide a barrier against moisture or gas, etc. , (iii) improving the storage stability of the recording layer, and (tv) improving the reflectance. Various polymeric materials such as ionomer resins, polyamide resins, vinyl resins, natural polymers, silicones, liquid rubbers, etc. can be used for the purpose (i), and for the purpose (n) is an inorganic compound such as SiO□ in addition to the above-mentioned polymeric material.

MgF, , Sin, Tie, , ZnO, etc.
Metals or metalloids such as Zn, Cu, Sn, Ni, Cr
, Ge, Ss, Cd, ^g, A Q, etc. can be used, and for the purpose of (iii), the above (i) and (
Materials such as those exemplified for ii) and for the purpose of (tv) metals such as Ag, i, etc. can be used. Further, the protective layer 4 is provided for the purpose of protecting against scratches, dust, dirt, etc. and improving the chemical stability of this protective layer, and the same material as the undercoat layer 3 can be used as the material thereof.

In the present invention, in place of or in combination with the cyanine dye and/or merocyanine dye, other dyes, low molecular compounds, high molecular compounds, etc. are used in combination with the compound of general formula (I). Representative examples of colors M (excluding cyanine dyes and merocyanine dyes) and compounds that can be mixed with such compounds of general formula (I) are shown in general formulas (Ill-1) to (m-], 4). However, it is not limited to this.

(m-1) Croconium dye (or a chromophore, Mo represents a cation,
Although Yo represents an anion, it is assumed that Yo does not exist when an anion is contained in the chromophore. ) (m-2) Azulene dye R', R'', R7, R'' and R'', hydrogen atom, 7/L
/represents a kill group, an alkoxy group, or a substituted or unsubstituted aryl group) (m-3) Triphuedithiazine compound (However, R"
and R'' may be the same or different, and each represents a hydrogen atom, halogen, alkyl group, phenyl group and alkyl group, alkoxy group, carboxyl group, carboxylic acid group, halogen, hydroxyl group, sulfonic acid group and sulfone (represents a phenyl group substituted with one or more acid bases) (m-4) Phenanthrene derivative RL2 R12 (However, R12 is -C) an alkyl group such as Il, -C,14, etc., and X is BF4 (represents C404, )i3! (However, R13 represents an alkyl group such as -CH, -C, H, etc., and X represents BF4.0Q04.) (III-5) Phthalocyanine compound (however, M
hydrogen, vanadium oxide, copper, beryllium, magnesium, calcium, zinc, cadmium, barium, aluminum, tin, lead, vanadium, chromium, manganese,
Examples include iron, cobalt, nickel, tin halide, aluminum halide, etc. Particularly preferred are hydrogen,
Examples include lead, nickel, cobalt, copper, vanadium oxide, aluminum chloride, and tin chloride. or hydrogen and halogens such as chlorine, bromine, iodine and fluorine. n is an integer from 1 to 16. ) (III-6) Tetradehydrocholine compound CH, CH.

(However, R" represents an alkyl or carbalkoxy group such as -000C2Hs, and R" represents hydrogen or an alkyl group. M is H, N1(II), Co(IF)
, Co(m), etc., and X is Br, c Qo
, etc.) (III-7) Dioxazine compounds and derivatives thereof a
) Ring-condensation reaction products of aromatic amines and fluoranyl, chloranil, bromanyl, iodoanil.

(However, A2 represents a residue of an unsubstituted or substituted aromatic amine, or -F, -CQ, -Br, -■, etc.) C2H.

(However, X represents -F, -Cfl, -Br, or -Work, R17 is -H1-No
,,-QC,! (-F, -CQ, -Br, -■ or an aromatic group, m and n are integers of 1 to 4.) (m-8) Anthraquinone derivative The following structural formula (8-1) and (8-2).

Structural formula (8-1) (Tatashi, Rls, R11, R” and R”l;!
Each represents hydrogen, an alkyl group, a hydroxyl group, a nitro group, an amino group, a cyano group, and a halogen. Y represents hydrogen and a sulfonate group. Ar1 represents hydrogen, a phenyl group, a naphthyl group, and sulfonated products and salts thereof, and the phenyl group is substituted with an alkyl group, an alkoxy group, an amino group, an alkylcarbonyl group, a methylthio group, a halogen, and a phenylcarbonyl group. Good too.

Ar2 represents a hydrogen atom, a phenyl group, and sulfonated products and salts thereof, and the phenyl group may be substituted with an alkyl group, an alkoxy group, an amino group, an alkylcarbonyl group, a phenylcarbonyl group, and a halogen.) Structural formula (8-2) (However, Rls, R19, R20 and R21 have the same meanings as above, R1 is a hydrogen atom and -NH-
Ar.

z3 represents a hydrogen atom, -NH-Ar, and -5
-represents Ar-type, and Ar-type has the same meaning as above. ) In particular, compounds with an indanthrene skeleton like structural formula (8-2) have a maximum absorption wavelength around 800 nm, so
It is ideal as a material for semiconductor lasers.

Examples of the anthraquinone derivatives represented by the above structural formulas (8-1) and (8-2) are as follows.

1-amino-4-(4-sulfonic acid phenylamino)
-6,7-sinitroanthraquinone sodium salt, 1-
Sodium anilino-2-sulfonate-4-(4-methylphenylamino)anthraquinone, 8.17-bis-
(4-methoxyphenylamino)-indanthrene, 1
．． 4-bis(sodium 3-sulfonate-4-methoxyphenylamino)-6,7-dicyazanthraquinone, 1,4-bis(sodium 3-sulfonate-4-chlorophenylamino)-5,8-dichloroanthraquinone, Sodium 1-(2-methylphenylamino)-2-sulfonate-4-(4-aminophenylamino)-6
, 7-sinitroanthraquinone, 1,4-bis(sodium 3-sulfonate-4-anilino-1-anthraquinolyl amino)benzene, 1,4-bis[4-(sodium 4-sulfonate-phenylamino) -1-anthraquinolyl aminocobenzene and the like can be mentioned.

(m-9) Xanthine compound (methane, R″31t-OH1=O or 1t=NHR26
(R"=C,=C1゜alkyl group), R24 is "N'(R")2.X-(X-: acid anion, RZ a
=c~C1゜alkyl group), R1 is -H,
C1-C2゜alkyl group, -3o, Na, -3o3H
1-5o2N CR"' )! (R"' :Cz
-C1O alkyl group), -COOHl-CQONa or -COO, ) (I[[-10) triphenylmethane compound (wherein RZI is -H1-N(R30), (R''=C- C1゜alkyl group), C1-C3゜alkyl group or -
〇〇 is the front side, R”Ji-Hl-N(R”), (R3
o=C,=C1゜7)Ltkyl group), 01-C2゜alkyl group or -OH, R1 is -H, C□-C2゜alkyl halogen, -5o, H or -N (R' 1
)z represents (R131=cm~C1° alkyl group) ye represents an anion, )(m-11) biryllium-based compound, , , , , , zzj, , .

(In the formula, X□ and X2: represent a sulfur atom, an oxygen atom, or a selenium atom.

z': From the necessary atomic group to complete pyrylium, thiopyrylium, selenapyrylium, benzopyrylium, benzothiopyrylium, benzoselenapyrylium, naphtopyrylium, naphthothiopyrylium or naphthoselenapyryllium, which may be substituted with w. This represents a hydrocarbon group.

Z5: Indicates a hydrocarbon group consisting of an atomic group necessary to complete pyran, thiopyran, selenapyran, benzopyran, benzothiopyran, benzoselenapyran, naphthopyran, naphthothiopyran or naphthothiopyran, which may be substituted.

R", R34Oyohi R3s: represents a hydrogen 5 atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group.

R'', R37 and R1: hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, or substituted or unsubstituted aralkyl group.

A. : Indicates an anion.

m and Q: 1 or 2.

n: indicates o, 1 or 2) (III-12) Squarylium-based compound (or indicates a chromophore; representative examples thereof include the following.

0θ (b) R39=R”=CH, R41=H, ZG:5
e(b) R”=C2HE, R”=CH,, R41=
H, Z'=Se(a) R42=CH.

(b) R’″: R5 e (a) R”=CH.

(b) R''=c2Hs (III-13) Low molecular compound plasticizer, surfactant, antistatic agent, lubricant, flame retardant, stabilizer, dispersant, antioxidant, light resistance improver, etc.

(III-14) High molecular compounds Various high molecular substances such as ionomer resins, polyamide resins, vinyl resins, natural polymers, silicones, liquid rubbers, and silane coupling agents.

The recording layer 2 can be formed by conventional means such as vapor deposition, sputtering, CVD or solution coating.

When a coating method is used, it is dissolved in an organic solvent such as dichloroethane and applied by a conventional coating method such as spraying, roller coating, dipping and spin coating. The thickness of the recording layer is 100-5
[mu]m Preferably 200 to 2 [mu]m is suitable.

Further, as shown in FIGS. 2 to 4, an undercoat layer 3 and/or a protective layer 4 are further provided, and the compound of the general formula (I) is added to at least one of the layers, thereby achieving the present invention. Able to achieve purpose. In this case, the recording layer 2 may or may not contain the compound, and the amount of the compound of general formula (I) added is preferably 2 to 60% by weight based on the total solid content of the recording layer. 5 to 40% by weight, and 2 to 90% by weight for the undercoat R3 or protective layer 4, preferably 10 to 50% by weight. Also,
The thickness of the undercoat layer 3 is 0.1 to 30μ, preferably 0.2 to 30μ.
The thickness of the protective layer is suitably in the range of 10 μm, and the thickness of the protective layer is preferably 0.1 μm or more, preferably 50 μm or more.

Typical examples of the optical information recording medium of the present invention are shown in FIGS. 1 to 4. In addition, two recording media having the same configuration as shown in FIGS. The organic thin film recording layer 2 may be placed inside and sealed using a so-called air-sand-inch structure, or a so-called adhesion sandwich structure (laminated structure) in which the organic thin-film recording layer 2 is placed inside and sealed (one substrate only) may be used. ).

Note that if a semiconductor laser with a wavelength of 750 to 850 nm is used as a laser light source, the device can be miniaturized.

Next, examples and comparative examples will be shown.

Example 1 Polymethyl methacrylate (rP) with a thickness of about 1.2I
A methyl ethyl ketone solution of the exemplified compound (G) was spin-coated onto a substrate (abbreviated as "MMA") to a thickness of about 1.2 μm.
An optical information recording medium was produced by forming a recording layer of m.

Example 2 On the recording layer formed in Example 1, a silver vapor deposition film having a thickness of approximately 150 mm was further provided to produce an optical information recording medium.

Example 3 The exemplified compound (E
) and the compound of the following formula (A) in a weight ratio of 1:1, a 1,2-dichloroethane solution was spin-coated to a thickness of about 7 cm.
A recording layer of 0.00 people was formed to produce an optical information recording medium.

Oθ Example 4 The above exemplary compound (
A methyl ethyl ketone solution containing B) and the compound of the following formula (b) mixed at a weight ratio of 6:4 was spin-coated to a thickness of approximately 60 mm.
Formed a layer of 0 people. Furthermore, a compound of the following formula (c) was vacuum-deposited to a thickness of about 150 layers to form a laminated type recording layer, thereby producing an optical information recording medium.

Cω4゜Example 5 The compound (C) used in Example 4 was evaporated to a thickness of about 100 on a PMMA substrate with a thickness of about 1.2+ am, and the 1,2- A dichlorothane solution was spin-coated to form a laminated type recording layer with a total thickness of about 600 layers to produce an optical information recording medium.

Example 6 An optical information recording medium was produced in the same manner as in Example 2 except that the recording layer was formed using the exemplified compound (H).

The six types of optical information recording media produced in the above example had a wavelength of 83
Information was written and reproduced from the substrate side using a 3n+m semiconductor laser beam at a recording frequency of 0.58) Iz and a linear velocity of 1.5 m/sec, and its spectrum analysis (scanning filter, bandwidth 30 KHz) was performed to determine the initial After measuring the reflectance and C/N, 540
The reflectance and C/N were measured after 50 hours of irradiation with 00 lux tungsten light. The results are summarized in Table-1.

Example 7 The dye of general formula (d) and the exemplified compound (A) were mixed in a weight ratio of 100:1.
5 in 1,2-dichloroethane, and this was dissolved in PMMA.
A recording layer having a thickness of approximately 500 layers was formed by spin coating on a substrate to produce an optical information recording medium.

Example 8 Example 7 except that in place of the dye and compound (A) described in Example 7, the dye of the following formula (e) and the exemplified compound (G) were used, and the mixing ratio was 100:30. An optical information recording medium was produced in the same manner as described above.

Example 9 An optical information recording medium was produced in the same manner as in Example 7 except that the foreplant exemplary compound (C) was used instead of the compound (A) described in Example 7.

Example 10 Example 7 except that in place of the dye and compound (A) recorded in Example 7, the dye of the following formula (H9) So, eSo, H and the exemplified compound (D) were used. An optical information recording medium was produced in the same manner as described above.

Example 11 The exemplified compound (D) and polycarbonate were dissolved in 1,2-dichloroethane at a weight ratio of 7:3, and the PH
An undercoat layer having a thickness of about 0.2 μm was formed by coating on an MA substrate, and a recording layer containing only the cyanine dye recorded in Example 10 was provided thereon to produce an optical information recording medium.

Example 12 On the recording layer formed in Example 10, a protective layer with a thickness of about 1 μm was provided by applying compound (A) and a polyamide resin dissolved in methanol at a weight ratio of 7:3 to provide optical information. A recording medium was produced.

Comparative Example 1 An optical information recording medium was produced in the same manner as in Example 7 except that a recording layer consisting only of the dye used in Example 7 was formed.

Comparative Example 2 An optical information recording medium was produced in the same manner as in Example 8, except that a recording layer consisting only of the dye (e) used in Example 8 was formed.

Comparative Example 3 An optical information recording medium was produced in the same manner as in Example 10, except that a recording layer consisting only of the dye used in Example 10 was formed.

The nine types of optical information recording media produced in this way were
90nm semiconductor laser light from the substrate side at a recording frequency of 0
．． The initial reflectance and C/
N was measured. Next, the same recording medium was irradiated with 54,000 lux tungsten light for 20 hours, and then the reflectance and C/N were measured. The results are summarized in Table-1.

Table 1 [Effects] The optical information recording medium of the present invention configured as described above has excellent optical stability and can endure multiple readings.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 4 are cross-sectional views showing the structure of the optical information recording medium of the present invention.

Claims (1)

[Claims] 1. The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) [However, in the formula, R^1, R^2: hydrogen atom or lower alkyl group, Ar
：Substituted or unsubstituted aromatic ring, Yes ▼ (if m is 2). ] An optical information recording medium characterized by being provided with an organic thin film recording layer containing a compound represented by: