JPS58224448A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To obtain an optical information recording medium high in recording sensitivity, by forming a reflection layer using a low melting metal or a dye having bronze gloss, and an absorption layer contg. a compd. having anthraquinone or indanthrene structure. CONSTITUTION:A reflection layer 2 contg. a low melting metal, such as Te, Bi, or alloy, or a dye having bronze gloss, such as cyanine or triphenylmethane type, is formed on a base 1, and a light absorption layer is formed on the layer 2 by vapor-depositing a compd. having anthraquinone or indanthrene structure or coating the layer 2 with a soln. contg. said compd. to obtain an optical information recordong medium. An undercoat layer 4 may be formed between the base 1 and the layer 2, and a protective layer 5, such as SiO2 layer, may be formed on the layer 3. The arrangement in which the layer 3 is formed on the base 1 and the layer 2 is formed on the layer 3 may be adopted. The recording medium thus obtained is capable of recoding semiconductor beams and being reproduced with said beams, and recording output beams lower than conventional ones.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel optical information recording medium comprising a combination of a reflective layer and an absorbing layer.

Conventionally, optical information recording media have been known to use a single layer of a material having a low melting point such as To or Bi, a single layer of a dye with bronze luster, or a laminate of a silver mirror and a dye as a recording material. . However, although a recording layer made only of Te%B1 or the like has a low melting point, the energy required for recording is somewhat large.

Furthermore, since a recording medium using a pigment with a bronze luster is sensitive only to light near the absorption wavelength of the pigment, there is a drawback that the sensitivity is rather low when a semiconductor laser is used. Furthermore, for the type in which a silver mirror and a dye are laminated, the required recording energy is about To and Bl.

The present invention has been devised in view of the above problems, and uses a low melting point metal or a pigment with bronze luster as a reflective layer, and a light absorbing layer is entirely laminated on this to improve recording sensitivity, particularly recording sensitivity in semiconductor lasers. The present invention has been completed by successfully improving this.

An object of the present invention is to lower the recording threshold value by using the combination K of a light-reflecting layer and a light-absorbing layer compared to a conventional recording medium having only a light-absorbing layer. Another object of the present invention is to obtain even higher recording sensitivity by fully using a low melting point metal or a dye with bronze luster in the reflective layer.

The optical information recording medium of the present invention is formed by laminating a reflective layer and an absorbing layer on a substrate in any order, wherein the reflective layer is not made of a low melting point metal or a pigment with bronze luster, and the absorbing layer is made of a low melting point metal or a pigment with bronze luster. The layer is characterized by being composed of a compound having an anthraquinone structure or an indanthrene structure, or a combination of a core compound and other components.

The optical information recording medium of the present invention basically consists of a substrate, a reflective layer, and an absorbing layer, but other layers such as a protective layer and an undercoat layer may be provided depending on the purpose. .

The low melting point metals used in the present invention include Bi, To
,Be,Sn,Gθ%Eng%As%Pb
% Zn and other metals exhibiting a relatively low melting point, or alloys such as 10n et al. The metal or its alloy is deposited on the substrate by, for example, vapor deposition or sputtering.
It can be applied in thicknesses of ~11000n.

In addition, pigments with bronze luster include cyanine mata, merocyanine pigments, iJ phenylmethane dyes,
Xanthine dyes, naphthoquinone dyes, squarenium dyes, phthalocyanine dyes, perylene pigments, dioxazine compounds, and the like can be used as appropriate. Examples include 2-(7-(3-ethyl-2-penzoteγzolinyritene)-i,s,s-hebutatrienyl]-3-
Ethylbenzothiazolium chloride, 2,4-bis-(
2,4,6-)lihydroxypheni/I/ ) -11
3-Cyclobutadienedaleium-1,3-dithiolate, 1,3-bis-[6-niterubenzthiazolinylidene-(21-methyl)-phenalenium tetrafluoroborate, N,N'- dianisole-substituted perylene,
0. Craftsmanship, smooth blue, magenta base, lead phthalocyanine% 0. Engineering.

Direct Blue 108 (0, engineering, 51320), 6
-Abano 3-hydroxy-9-(2-carboxyphenyl)-xanthylium chloride, 0. Engineering.

Examples include Vaat Blue-1 (o, 1.7300) and methylene blue. In the present invention, a plurality of the above dyes may be combined. The bronze luster pigment according to the invention is applied to a substrate in a thickness of 10 to 11,000 nm, for example, by vapor deposition or solvent coating.

The compound used as the absorbent layer in the present invention has the following structural formula q and a substituent on the anthraquinone skeleton or indanthrene skeleton.

(al Structure symbol 5- (in the formula, 11, X2, X3 and X4n represents hydrogen, alkyl group, hydroxyl group, nitro group, amine group, cyano group and]. represents a sulfonate group, Ar1 represents hydrogen, a phenyl group, a naphthyl group, or a sulfonated product or salt of the same, and the phenyl group represents an alkyl group, an alkoxy group, an amine group, an alkylcarbonyl group, a methylthio group,
Ar2 may be substituted with hydrogen, phenyl group, -〇- and their sulfonates and salts.
(The above phenyl group may be substituted with an alkyl group, an alkoxy group-abano group, an alkylcarbonyl group, a phenylcarbonyl group, and a halogen).

(bl Structural formula l) (In the formula, xl, x2, X3 and x4 have the same meanings as above, and X5 is hydrogen -NH-Ar1 and -8-Ar
'ii represents hydrogen, -NH-Ar1 and -8-
(where Ar1'i is represented, Ar1 has the same meaning as above)0 In particular, compounds with an indanthrene skeleton as in structural formula l have a maximum absorption wavelength around 800 nm, so
It is ideal as a material for semiconductor lasers.

Examples of anthraquinone conductors represented by the above structural formula (1) and symbols are shown below.

1-Abano 4-(4-sulfonic acid phenylamino)
-6,7-sinitroanthraquinone sodium salt, 1-
Anilino-2-sulfonic acid nato IJ Rum salt-4-(4
-methylphenylazeno)anthraquinone, 8.1
7-bis-(4-methoxyphenyla 1))-(endanthrene% i, 4-bis(sodium 6-sulfonate-4-methoxyphenyla)) -6,7-dicyazanthraquinone, 1.4- Bis(sodium 5-sulfonate-4-chlorophenyla 1))-s,a-dichloroanthraquinone, 1-(2-methylphenylaz))-
Sodium 2-sulfonate-4-(4-azunophenylamino)-6,7-sinitroanthraquinone, 1.4
-His(sodium 6-sulfonate-4-7 nilino 1
-anthraquinolylag))benzene, 1,4-bis(
4-(4-Sodium sulfonate-phenyla(/)-
1-Anthraquinolylγnno)benzene, 1#4-bisanilinoanthraquinone, 1.4-bis(4-methylphenylaino)anthraquinone, 1.4-bis(4-methoxyphenyla<))anthraquinone, 1.4 -bis(4-annophenylaba))anthraquinone, 1.4
-bis(4-penzoylphenylazeno)anthraquinonet1.4-his(4-riprophenylai))anthraquinone, 1,4-bis(4-aceterphenylamino)anthraquinone, 1.4-bis(naphthylaino) ) Anthraquinone, 1,4-bis(sodium 4-sulfonate phenylazeno)anthraquinone, 1,4-bis(6
-sodium sulfonate-4-methylphenylaino)
Anthraquinone 9-one, 1,4-bis(3-sulfonic acid-4-methoxyphenylazeno)anthraquinone, 1,4-bisanilino-
6,7-sinitroanthraquinone, 1-7=1. ! 4-(4-methylphenylaino)-6,7-sinitroanthraquinone, 1,4-bis(4-sulfonic acid sodium phenylaino)-6,7-dicyazanthraquinone, 1-anitroanthraquinone/ -4-(4-nitrophenylamino)anthraquinone, 1-(4-methoxyphenylγt/)-4-(4-nitrophenyla<))-anthraquinone, terephthalazade, N,N'-bis-12-
1'Romo4-(2-methylthioanilino)-1-anthraquinolyl), 1-(4-sodium sulfonate phenylazeno) -4-(4-methyl-3-sulfonate sodium phenylazeno) -5, 8-cyanoanthraquinone, 1,4-bis(4-methylphenylγi/
) -6,7-10- dichloroanthraquinone, 1,4-bis(4-ethoxyphenylaξ)) -6,7-sinitroanthraquinone% 8. i7-his(4-methylphenylaz))indanthrene, 8.17-bis(4-chlorophenylaz))indanthrene, 2,3.11.12-titranitro-8,17-bisanili Noindan Ren s
6,15-His(2-methylthiophenylamino)indanthrene, 6.15-bis-(6,5-dimethoxyphenylamino)indanthrene, 8.17-His(anilino)indanthrene, 8.17 -Bis(sodium 4-sulfonate phenylamino)indanthray, 8.1
7-bisphenylthioindanthrene% a, R=His(2-methoxyphenylaξ))indanthrene% 8
, 17-his(5-methoxyphenylthiono)indanthrene, 8.17-his(2-methylphenylamino)
Indanthrene% 8. i7-His(3-Methylphenylaba))Indanthrene% 8.17-His(2-
chlorophenylamino)indanthrene, 8.17-bis(3-chlorophenylamino)indanthrene s 8
．． i7-His(2-methylthiophenylamino)indanthrene, 8.17-bis(6-methylthiophenylamino)indanthrene, 8.17-bis(4-methylthiophenylamino)indanthrene, 8.17- his(4-phenylthiophenylamine) indanthrene,
8. i7-His(2,5-dimethoxyphenylamino)indanthrene, 8,17-bis(4-methyl-2-
chlorophenylamino)indanthrene, B, 17-his(2,4,6-)limethylphenylamino)indanthrene, 8.17-bis(1-naphthylamino)indanthrene, 8.17-bis( 2-naphthylamino)indanthrene, 8.17-bis(2-methoxyphenylthio)indanthrene, 8.17-bis(4-
Phenylphenyl 7! , /) Indanthrene, 8.17
-bis(2-methoxy-4-sulfonic acid sodium phenylamino)indanthrene, 8.17-bis(3-
Sodium methoxy-4-sulfonate (phenylamino)
Indanthrene, 8.17-bis(4-methoxy-2-
Sodium sulfonate phenylamino)indanthrene, 8.17-Bis(2-methyl-4-sulfonate sodium phenylamino)indanthrene% 8,17-
his(sodium 6-methyl-4-sulfonate phenylamino)indanthrene, 8.17-his(sodium 4-methyl-2-sulfonate phenylamino)indanthrene, 8.17-binu(2-methylthio) -4-Sodium sulfonate phenyl aba)) Indanthrene s 8
+17-His(3-methylthio-4-sulfonate sodium phenylamino))indanthrene, 8.17-Bis(4-methy13-luna-2-sulfonate sodium phenylamino)indanthrene, 8,17- Bis(4-(4-sodium phenylthio)sulfonate phenylazenocoindanthrene s B,1y-his(2,5-dimethoxy-4-sulfonate sodium phenylamino)indanthrene s
B, '+7-his[1-(4-sodium naphthyl sulfonate) azenocoindanthrene, 8,17-bis(
2-(4-sodium naphthyl sulfonate) ainocoindanthrene, 8.17-his(4-hydroxyphene)
Indanthrene, 8,17-his(3-
Hydroxyphenylazeno)indanthrene, 8.17
-His(2-hydroxyphenylamino))indanthrene, 6+15-his(2-10lophenylamino)indanthrene% 6115-bis(6-chlorophenylamino))indanthrene, 6.15-bis( 4=chlorophenylat)) indan-14-threne, 6.15-his(2-methylphenylthiono)
Indanthrene, 6.15-bis(6-methylphenylthiono)indanthrene, 6.15-bis(4-methylphenylthiono))indanthrene, 6.15-bis(4-lychloro2 -Methylphenyl aba)) indanthrene, 6.15-bis(3=(methylthio)phenylazenocoindanthrene, 6.15-bis(2-(methylthio)phenylazenocoindanthrene s 6,15) −
Bis(2-methoxyphenylamino)indanthrene%
6. i5-his(3-methoxyphenylaz))indanthrene, 6.15-his(4-methoxyphenylaz))indanthrene % 6.15-his(4-di)=
? Cyphenylabano)indanthrene% 6.15-bis(1-naphthylabano))indanthrene%6.15-
Bis(2-naphthylazeno)indanthrene, 6.1s
-His(4-(phenylthio)phenylaminocoindanthrene, 6.15-bis(2-chloro-4-sulfonic acid sodium phenylaba))indanthrene% 6.
i5-His(sodium phenyl 3-chloro-4-sulfonate Tε)) indanthrene, 6,15-bis(4-
Sodium chloro-2-sulfonate phenylamine) indanthrene, 6.15-bis(sodium 2-methyl-4-sulfonate-phenylamine) indanthrene%
6.15-bis(sodium 3-methyl-4-sulfonate-phenylamine))indanthrene, 6.15-bis(sodium 4-methyl-5-sulfonate-phenylamine)indanthrene, 6 .15-bis(sodium 2-methoxy-4-sulfonate-phenyla ξ)) indanthrene, 6.15-bis(sodium 3-methoxy-4-sulfonate-phenyla ξ)) indanthrene,
6.15-bis(4-methoxy-2-sulfonic acid sodium phenylaba))indanthrene, 6.15-bis(4-aminophenylthio)indanthrene, 6.1
5-his(4-methylphenylthio)indanthrene,
6.15-bis(sodium 4-sulfonate-phenylthio)indanthrene O As mentioned above, the absorption layer in the present invention is composed of a compound having an anthraquinone structure "1.fC" alone or together with other components ( (including other dyes).

The absorption layer can be formed by dissolving the above compound in a solvent and applying it, by vapor deposition, by mixing it with a resin solution, by co-evaporating it with other dyes, or by applying a mixed bath solution with other dyes. It is formed by dissolving it in a resin solution together with other pigments and applying it. In this case, known resins such as PVA%PVP, polyvinyl butyral, and polycarbonate are used, and the amount of the above compound relative to the resin is preferably 0.01 or more in weight ratio. In addition, other types of anthraquinone derivatives may be used as other dyes, or dyes that have absorption outside the wavelength range of semiconductor lasers, such as thoria dyes, methane-based dyes, and azo dyes, are recommended. This is suitable because it is possible to obtain a medium that can be recorded using an Nθ laser or the like. The thickness of the absorption layer is 0.01 to 1 μm, preferably 0.0
It is in the range of 5 to 0.5 μm.

Next, the entire structure of the optical information recording medium of the present invention will be described below with reference to the drawings.

FIG. 1 is a conceptual diagram showing the basic structure of the recording medium of the present invention, in which a reflective layer 2 is provided on a substrate 1, and an absorbing layer 1@3 is further provided thereon.

As the substrate, transparent materials 18- such as glass and plastics such as acrylic and polycarbonate can be used. Furthermore, there is no problem in providing the undercoat layer 4 and/or the protective layer 5.

FIG. 2 shows an example in which both of these are provided. Information is recorded through the substrate.

In addition, a configuration as shown in FIG. 3 is also possible, and the substrate 1
An absorbing layer 6 is provided thereon, and a reflective layer 2 is further provided thereon. In this case, as the substrate, in addition to glass and plastics such as acrylic and polycarbonate, metals such as iron and aluminium can also be used. Also,
There is no problem in providing both or one of the undercoat layer 4 and the protective layer 5. FIG. 4 shows an example in which both of these are provided. Information is recorded from the reflective layer side. When the reflective layer is on the substrate side, a configuration in which two reflective layers are placed back to back as shown in FIG. 5 is also possible.

Information can be recorded by irradiating a high-energy beam such as a laser from the side of the sporatra reflective layer, but the absorbed heat can cause holes in the recording layer and result in no recording. Of course, recording from the absorption layer side is also possible. Further, information can be read by irradiating a low-power laser beam and detecting a change in the amount of emitted light.

The present invention will be explained in more detail with reference to Examples below, but is not limited thereto.

Example 1 A reflective layer was obtained by vapor deposition on an acrylic plate to a total thickness of Tθ of 1'00 nm. Furthermore, on top of this, 8.17-bis(4-phenylphenylaξ))indanthrene was added to a thickness of 150 nm.
It was vapor-deposited to form a light absorption layer.

The reflectance and transmittance of the N5 recording medium thus obtained at 800 nm were 45% and 2%, respectively.

This recording medium was irradiated with a semiconductor laser beam with an irradiation surface energy of 3 mW and a beam diameter of 1.6 μm to obtain an I MH2
The signal was recorded.

The recording threshold per pit was a6n, T/pit, and the pit diameter was 1.6 μm and 7t.

Example 2 A glass plate was coated with polyvinyl petyral to a thickness of 1.5 μm to serve as an undercoat layer. Co-deposited on this substrate at a ratio of 8e and nff of 12:1 to a thickness of 11:1.
A reflective layer of 00n was obtained. Furthermore, on top of this, polyvinylallol 0.5v water
A light absorption layer was obtained by spin-coating a solution of 1(18,17zes(2-methoxy-4-sulfonic acid 0,3vphenylazeno)indanthrene) with a composition of p.
e21- The reflectance and transmittance at 800 nm of the nJ'c recording medium thus obtained were 337% and 1%, respectively.

When information was recorded on this recording medium in the same manner as in Example 1, pits with a diameter of 1.4 μm were formed at a recording threshold of 0.7 nJ/pit.

Example 3 As10Se3oTe6 with a thickness of 7 Qnm on an acrylic plate
o A vapor deposited film was provided to serve as a reflective layer. Further, a light absorbing layer was obtained by coating a bath solution having a composition of non-dichloroethane 10F on top of this.◎ The reflectance and transmittance at 800 nm of the nfC recording medium thus obtained were 33% and 12%, respectively. %Met.

22- When information was recorded on this recording medium in the same manner as in Example 1, the recording threshold was 1.2 nJ/pit and the diameter was 1.2μ.
m pits were formed.

Example 4 A solution consisting of 10 V of zolium chloride dichloroethane was completely spin-coated on a polysulfone resin plate with a thickness of 1.5 mm to obtain a reflective layer of bronze pigment. Further, a light absorption layer was obtained by vapor depositing on this to a thickness of 8.17-bisanilinoindanthre/'fr 70 nm. The reflectance and transmittance of the recording medium thus obtained were as follows: They were 27% and 16%.

When information was recorded on this recording medium in the same manner as in Example 1, pits with a diameter of 1.2 μm were formed at a recording threshold value α7n:r/bit.

Example 5 Acrylic plate Ks coated with polyvinyl alcohol to a total thickness of 1.5 μm 2,4-bis-(2,4,6-)lihydroxyphenyl)-1,3-cyclobutadienedaleium-1, A reflective layer was obtained by depositing 3-diolate k to a thickness of 50 nm. Additionally, K 8,17-bis(4-chlorophenylamino)indanthreneffi
A light absorption layer was obtained by vapor deposition to a thickness of 100 nm.

The reflectance and transmittance of the thus obtained recording medium were 331% and 6%, respectively. When information was completely recorded on this recording medium in the same manner as in Example 1, the recording threshold was 0. 7nJ/pit diameter 1.3
Pits of μm were formed.

Examples 6 to 14 A recording medium was obtained by forming a reflective layer and a light absorbing layer on an acrylic substrate using the materials shown in the table below. , the friend recording thresholds shown in the table were obtained.

-25= Example 15 A light absorption layer was obtained by vapor depositing 8.17-bis(4-phenylamino)indanthrene kJl to a thickness of 100 nm on a surface-hardened acrylic plate. Furthermore, on top of this, B1 is added to a thickness of 50 nm.
A light reflecting layer was formed by vapor deposition.

The reflectance and transmittance of the recording medium thus obtained at 800 nm were 68% and 6%, respectively.

When all signals were recorded on this recording medium in the same manner as in Example 1, pits with a diameter of 1.4 μm were formed at a recording threshold of 0.4 nJ/bit (n-fc).

, Example 16 A photopolymerizable methyl methacrylate monomer was applied to a glass substrate and cured by ultraviolet irradiation to obtain an undercoat layer.

On this substrate, 6,15-bis(4-aminophenylthio)indanthrene was vapor-deposited to a thickness of 1100 nm to obtain a light absorption layer. Additionally, on top of this, you're adding a thickness of 5
It was deposited to a thickness of 0 nm and closed for light reflection.

The reflectance and transmittance at 800 nm of the recording medium thus obtained were 42% and 4%. This recording medium was coated with information in the same manner as in Example 1. @When all recording was performed, pits with a diameter of 1.4 μm were formed at a recording threshold of 0.4 nJ/bit.

Example 17 S10 was deposited to a thickness of 50 mm on the recording medium obtained in Example 16.
The film was vapor-deposited to a thickness of 0 nm to form HorintW.

When signals were recorded in the same manner as in Example 1, pits with a diameter of 1.2 μm were formed at a recording threshold of α7nJ/pit.
did.

Regarding other low melting point metals or pigments with bronze luster or γ/traquinone derivatives used in the present invention,
When all optical recording media were prepared and information was recorded in the same manner as method 28- described in the above example, similar characteristics were obtained.

The optical recording medium of the present invention constructed as described above has absorption in the wavelength range of a semiconductor laser, is highly stable, and has an immediate effect on long-term information storage. .

[Brief explanation of drawings]

1 to 5 are conceptual diagrams showing the structure of the optical information recording medium of the present invention. DESCRIPTION OF SYMBOLS 1...Substrate, 2...Scale layer, 6...Absorption layer, 4...
...Undercoat layer, 5...Holding #'j1MA, 6...Spacer. Patent applicant Rico Co., Ltd. 129-295

Claims (1)

[Claims] In an optical information recording medium comprising a reflective layer and an absorbing layer laminated in any order on a substrate, the reflective layer is made of a low melting point metal or a pigment with bronze luster, and the absorbing layer has an anthraquinone structure. An optical information recording medium characterized by being composed of a compound having an i2dance structure or a combination of the compound and other components.