JP2005071492A - Optical information recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make reflectivity not more than 25% while keeping jitter, one of recording/reproducing characteristics low even in an optical recording medium consisting of a reflection layer and a recording layer formed of an organic dye. <P>SOLUTION: The optical information recording medium is provided with the reflection layer and the recording layer formed on a substrate in this order. The recording layer includes the organic dye. An interface layer is arranged between the reflection layer and the recording layer. It is desirable that the reflection layer includes Ag as a main component, and that the interface layer includes N and Al. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical information recording medium, and more particularly to a write-once optical information recording medium capable of recording and reproducing information using a laser beam.

  Conventionally, media such as so-called CD-R / RW and DVD-R / RW / RAM are known as optical information recording media capable of recording information by laser light. Among them, the CD-R is widely used because of its price and ease of use. The CD-R is manufactured by a method in which a thin film is formed on a substrate by a spin coating method and provided as a recording layer. This manufacturing method has a layer structure when compared with a RW phase change medium. Is simple, and a large-scale vacuum film-forming apparatus is not required. Therefore, there is a merit that a large number of optical disks can be manufactured at low cost, and the same manufacturing method is adopted in DVD-R.

  In recent years, with the progress of digitalization of broadcasting, the spread of networks such as cable TV, and the spread of high-definition TV, it has become an environment where high-quality video can be enjoyed at home. In such an environment, DVD discs have been used instead of VHS tapes that have long been used as media capable of reproducing high-quality images and media capable of storing high-quality images. In addition to the read-only ROM, the types of DVD disks include the above-described write-once medium DVD ± R, the rewritable DVD ± RW / RAM, and the like. Is becoming mainstream instead of VHS tape.

  Recently, with the start of digital high-definition broadcasting coming soon, a further increase in the amount of image data is expected, and as a result, high capacity and high data transfer speed are also required for recording media. It was. When trying to record a digital high-definition broadcast at home, the above-described DVD ± R is already said to have insufficient capacity, and a next-generation DVD is being developed. As an example, a Blu-ray disc recorder that can record and play back BS digital high-definition broadcasting for 2 hours was released this year.

  A recording medium for this Blu-ray disc recorder was also released at the same time, which was a medium having a phase change recording layer. As described above, the production of the phase change medium requires a large-scale vacuum film forming apparatus or the layer structure is complicated. In view of this, development of a write-once medium using an organic dye is also underway in order to produce a recording medium at a lower cost even in the next-generation DVD system including the Blu-ray disc. In the case of adopting a method of forming a film of an organic dye by spin coating, there is an advantage that manufacturing equipment that has been used for manufacturing CD-R and DVD-R can be continuously used.

  By the way, the optical disc using the organic dye and the phase change type optical disc have greatly different reflectivities, and the optical disc using the organic dye has a higher reflectivity. There are similar differences between CD-R and RW and DVD ± R and RW, and conventionally, different reflectance standards have been adopted.

  When considering compatibility with the aforementioned Blu-ray Disc system, or when considering a new optical disc system in the future, even if the optical disc using organic dyes can have the same reflectance as a phase change optical disc, the system This is a great advantage in terms of design and standards. However, like CD-R and DVD ± R, the reflectivity of the write-once next-generation DVD medium in which an organic dye is formed by spin coating is higher than the reflectivity of the phase change medium.

  As a method of reducing the reflectance, a method of providing a dielectric layer or the like on one side or both sides of the recording layer is known (see, for example, Patent Documents 1 to 3). However, such a method is applied to a rewritable phase change medium, and (1) control of the amount of heat accumulated in the recording layer, (2) repeated rewriting stability, and (3) the recording layer with external moisture. The function that protects it from the design, etc. is considered. Therefore, even if such a dielectric layer for a phase change medium is applied to a write-once medium using an organic dye, the reflectance cannot always be adjusted sufficiently.

  On the other hand, for write-once media, it has been proposed to adjust the reflectance by disposing a dielectric on at least one side of the recording layer (see, for example, Patent Document 4), which uses an inorganic material for the recording layer, In addition, the reflectivity is adjusted including the two recording layers, and the medium using the organic dye has not been sufficiently studied.

  Regarding adding a layer to a write-once medium using an organic dye as a recording layer, the reflective layer is made into two layers (see, for example, Patent Document 5), and an intermediate layer is provided between the recording layer and the reflective layer. (See, for example, Patent Document 6), but these are for keeping the reflectance high and suppressing the reaction between the recording layer and the reflective layer, and are not necessarily applied to the reduction of the reflectance. Can not.

  Moreover, although it has been proposed to insert a functional layer between the dye layer and the light transmission layer (see, for example, Patent Document 7), the main purpose is to prevent alteration of the dye layer when the light transmission layer is formed. In this configuration, the reflectance cannot be adjusted.

International Publication No. 97/32304 Pamphlet JP 2001-76390 A JP2002-117777 JP 2003-168242 A JP-A-6-76361 JP-A-6-195746 JP 2003-45083 A

  In view of the above, it is an object of the present invention to achieve the following object. That is, the present invention has a reflection layer, and even in an optical information recording medium using an organic dye as a recording layer, the reflectance is 25% or less while keeping jitter, which is one of the recording and reproducing characteristics, low. It is an object of the present invention to provide an optical information recording medium that can be used.

As a result of intensive studies to solve the above problems, the present inventor has conceived the following present invention and found that the problems can be solved.
That is, the present invention is an optical information recording medium comprising at least a reflective layer and a recording layer in this order on a substrate, wherein the recording layer contains an organic dye, and the reflective layer, the recording layer, An optical information recording medium comprising an interfacial layer therebetween.
The reflective layer preferably contains Ag as a main component. The interface layer preferably contains N and Al.

  The optical information recording medium of the present invention has a recording layer made of an organic dye, and even if the optical information recording medium has a reflective layer having a high reflectance, the reflectance can be increased without impairing the recording and reproducing characteristics such as jitter. 25% or less (reflectance equivalent to that of the phase change type optical information recording medium).

  The optical information recording medium of the present invention comprises at least a reflective layer and a recording layer in this order on a substrate, the recording layer contains an organic dye, and an interface layer is provided between the reflective layer and the recording layer. Become.

  By providing an interface layer between the reflective layer and the recording layer, even when a reflective layer having high reflectivity containing Ag, an Ag alloy, or the like is provided, the reflectivity can be 25% or less. That is, when the reflectance is high, by forming the interface layer, it is possible to reduce the reflectance to 25% or less while maintaining good characteristics such as jitter.

As the material for the interface layer, oxides, nitrides and the like can be used, but considering practicality, nitrides are preferable, and in particular, nitrides containing Al (compounds containing N and Al). ) Is preferable.
The thickness of the interface layer depends on the material of the reflective layer and the like, but is preferably 1 to 50 nm, and more preferably 0.5 to 10 nm.

  When a nitride containing Al is used as the interface layer, the atomic ratio (N / Al) between N and Al in the interface layer is preferably 5/95 to 40/60. By setting it as such a range, a jitter can also be made favorable, making a reflectance into the above-mentioned range. N / Al is more preferably 10/90 to 35/65, and further preferably 20/80 to 30/70.

The interface layer can be formed by a vacuum film forming method such as sputtering. For example, when a nitride containing Al is used as the interface layer, it can be formed by reactive sputtering using nitrogen gas. At this time, the flow rate of nitrogen gas is preferably 0.5 to 50 sccm (0.5 to 50 cm ³ / min).

  Alternatively, it can be formed by sputtering using an aluminum nitride target having a predetermined atomic ratio. The atomic ratio of N and Al in the interface layer can be obtained by measuring the ESC (X-ray photoelectron spectroscopy) after forming the interface layer.

A typical configuration of the optical information recording medium of the present invention includes a configuration in which a reflective layer, an interface layer, a recording layer, an adhesive layer, a transparent sheet or a light transmission layer are sequentially provided on a substrate. If necessary, an undercoat layer, a barrier layer (dielectric layer) or the like may be formed.
Hereinafter, the substrate and other layers of the optical information recording medium of the present invention will be described using the optical information recording medium as a specific example. The present invention is not limited to these.

(substrate)
Specific examples of substrate materials include glass; acrylic resins such as polycarbonate and polymethyl methacrylate; vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymers; epoxy resins; amorphous polyolefins; polyesters; metals such as aluminum; These may be used together if desired.
Among the above materials, polycarbonate and amorphous polyolefin are preferable, and polycarbonate is particularly preferable from the viewpoints of moisture resistance, dimensional stability, and low cost. Further, the thickness of the substrate (the average thickness of the region where the recording layer is formed) is preferably in the range of 1.1 ± 0.3 mm.

  On the substrate, a guide groove for tracking or an unevenness representing information such as an address signal (the convex portion of the substrate is called an on-groove and the concave portion is called an in-groove. Here, “on-groove” is sometimes called “groove”. .) Is formed. In order to achieve a higher recording density, it is preferable to use a substrate on which grooves having a narrower track pitch are formed as compared with CD-R and DVD-R.

The track pitch of the groove is preferably in the range of 300 to 360 nm. More preferably, the range is 310 to 340 nm.
Moreover, it is preferable to make the depth (groove depth) of a groove into the range of 20-50 nm. By setting it as such a range, it becomes possible to prevent the molding from becoming difficult while preventing the tracking error signal from becoming small and making tracking difficult. More preferably, it is 25-40 nm.

  The groove width (on-groove half-value width) is preferably in the range of 50 to 200 nm. By setting this range, it is possible to reduce jitter while preventing a tracking error from being lowered. More preferably, it is set as the range of 70-190 nm, More preferably, it is set as 90-180 nm.

An undercoat layer may be formed on the surface of the substrate on the side where a reflective layer, which will be described later, is provided for the purpose of improving flatness and adhesion.
Examples of the material for the undercoat layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, and chloro. Polymer materials such as sulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate, etc .; silane coupling Surface modifiers such as agents;
The undercoat layer is formed by dissolving or dispersing the above materials in an appropriate solvent to prepare a coating solution, and then applying this coating solution to the substrate surface by a coating method such as spin coating, dip coating, or extrusion coating. can do. The thickness of the undercoat layer is generally in the range of 0.005 to 20 μm, and preferably in the range of 0.01 to 10 μm.

(Reflective layer)
For the reflective layer, a light reflective material having a high reflectance with respect to the laser beam is used. The reflectance is preferably 70% or more.
As a light reflecting material having high reflectance, Mg, Se, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Ru, Rh, Pd , Ir, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Si, Ge, Te, Pb, Po, Sn, Bi, and other metals and semi-metals or stainless steel. These light reflecting materials may be used alone, or may be used in combination of two or more kinds or as an alloy. Among these, Cr, Ni, Pt, Cu, Ag, Au, Al, and stainless steel are preferable. Particularly preferred is Au, Ag, Al or an alloy thereof, and most preferred is Ag or an alloy containing Ag as a main component (Ag: 50% by mass or more).

  The reflective layer can be formed on the substrate, for example, by vapor deposition, sputtering or ion plating of the light reflective material. The thickness of the reflective layer is generally in the range of 10 to 300 nm and preferably in the range of 50 to 200 nm.

(Interface layer)
The details of the interface layer are as described above, and are formed on the reflective layer.

(Recording layer)
The recording layer is a layer formed on the interface layer and capable of recording information with a laser beam having a wavelength of 500 nm or less, and is preferably a dye type containing an organic dye.
Specific examples of the organic dye include a cyanine dye, an oxonol dye, a metal complex dye, an azo dye, and a phthalocyanine dye.

Examples of the organic dye include JP-A-4-74690, JP-A-8-127174, JP-A-11-53758, JP-A-11-334204, JP-A-11-334205, and JP-A-11-334206. 11-334207, JP-A 2000-43423, 2000-108513, 2000-158818, and the like are preferably used.
Furthermore, organic compounds such as triazole compounds, triazine compounds, cyanine compounds, merocyanine compounds, aminobutadiene compounds, phthalocyanine compounds, cinnamic acid compounds, viologen compounds, azo compounds, oxonol benzoxazole compounds, and benzotriazole compounds can also be used as recording layer materials. Preferably used. Among these compounds, cyanine compounds, aminobutadiene compounds, benzotriazole compounds, and phthalocyanine compounds are particularly preferable.

  The recording layer is prepared by dissolving a recording substance, which is an organic dye, in a suitable solvent together with a binder and the like, and then coating the coating liquid on the reflective layer formed on the substrate surface. After forming, it is formed by drying. The concentration of the recording substance in the coating solution is generally in the range of 0.01 to 15% by mass, preferably in the range of 0.1 to 10% by mass, more preferably in the range of 0.5 to 5% by mass, and most preferably. Is in the range of 0.5-3 mass%.

Examples of the solvent for the coating solution include esters such as butyl acetate, ethyl lactate and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane and chloroform; dimethylformamide and the like Amides; Hydrocarbons such as methylcyclohexane; Ethers such as tetrahydrofuran, ethyl ether, dioxane; Alcohols such as ethanol, n-propanol, isopropanol, n-butanol diacetone alcohol; 2,2,3,3-tetrafluoropropanol, etc. Fluorinated solvents; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether; That.
The above solvents can be used alone or in combination of two or more in consideration of the solubility of the recording material used. Various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be further added to the coating solution depending on the purpose.

  When a binder is used, examples of the binder include natural organic polymer materials such as gelatin, cellulose derivatives, dextran, rosin, and rubber; hydrocarbon resins such as polyethylene, polypropylene, polystyrene, and polyisobutylene; Vinyl resins such as vinyl, polyvinylidene chloride, polyvinyl chloride / polyvinyl acetate copolymer, acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resin, butyral resin, rubber And synthetic organic polymers such as initial condensates of thermosetting resins such as derivatives and phenol / formaldehyde resins. When a binder is used in combination as a material for the recording layer, the amount of binder used is generally in the range of 0.01 times to 50 times (mass ratio), preferably 0.1 times the recording substance. The amount is in the range of 5 to 5 times (mass ratio). The concentration of the recording substance in the coating solution thus prepared is generally in the range of 0.01 to 10% by mass, preferably in the range of 0.1 to 5% by mass.

  Examples of the coating method include a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, and a screen printing method. The recording layer may be a single layer or a multilayer. The recording layer generally has a thickness in the range of 20 to 500 nm, preferably in the range of 30 to 300 nm, and more preferably in the range of 50 to 100 nm.

The recording layer can contain various anti-fading agents in order to improve the light resistance of the recording layer.
As the antifading agent, a singlet oxygen quencher is generally used. As the singlet oxygen quencher, those described in publications such as known patent specifications can be used.
Specific examples thereof include JP-A Nos. 58-175893, 59-81194, 60-18387, 60-19586, 60-19587, and 60-35054. 60-36190, 60-36191, 60-44554, 60-44555, 60-44389, 60-44390, 60-54892, JP-A-60-47069, JP-A-63-209995, JP-A-4-25492, JP-B-1-38680, JP-A-6-26028, etc., German Patent 350399, and Japan Examples include those described in Chemical Society Journal, October 1992, page 1141.

  The amount of the antifading agent such as the singlet oxygen quencher used is usually in the range of 0.1 to 50% by mass, preferably in the range of 0.5 to 45% by mass, based on the amount of the dye. Preferably, it is the range of 3-40 mass%, Most preferably, it is the range of 5-25 mass%.

A barrier layer may be formed between the recording layer and a transparent sheet described later. By forming such a layer, it is possible to prevent moisture and organic components from diffusing into the recording layer.
The material constituting the barrier layer is not particularly limited as long as it is a material that transmits laser light, but is preferably a dielectric, and more specifically, ZnS, ZnO, ZnO—Ga ₂ O ₃ , ZnO—Al ₂ O ₃ , TiO ₂ , SiO ₂ , ZnS—SiO ₂ , GeO ₂ , Si ₃ N ₄ , Ge ₃ N ₄ , MgF ₂ , and other inorganic oxides, nitrides, sulfides, and the like _{-Ga 2 O 3, ZnO-Al} 2 O 3, ZnS-SiO 2, or SiO ₂ are preferred. The barrier layer can be formed by sputtering, ion plating, or the like, and the thickness is preferably 1 to 100 nm.

(Transparent sheet, light transmission layer)
The transparent sheet is formed to prevent the inside of the optical information recording medium from being contaminated, scratched, impacted, or to prevent moisture from entering. The material is not particularly limited as long as it is a transparent material, but is preferably polycarbonate, cellulose triacetate, or the like, and more preferably a material having a moisture absorption rate of 5% or less at 23 ° C. and 50% RH.
Note that “transparent” means that the recording light and the reproduction light are so transparent that the light is transmitted (transmittance: 90% or more).

The transparent sheet can be provided as follows, for example. After preparing a coating solution by dissolving the photocurable resin in an appropriate solvent, this coating solution is applied onto the recording layer (if a barrier layer or the like is formed) at a predetermined temperature to form a coating film. For example, a cellulose triacetate film (TAC film) obtained by, for example, plastic extrusion is laminated on the coating film, and the coating film is cured by irradiating light from the laminated TAC film. Is done. The TAC film preferably contains an ultraviolet absorber. The thickness of the transparent sheet is in the range of 0.01 to 0.2 mm, preferably in the range of 0.03 to 0.1 mm, and more preferably in the range of 0.05 to 0.095 mm.
In addition, a polycarbonate sheet etc. can also be used as a transparent sheet.
Moreover, you may form the light transmissive layer which consists of ultraviolet curable resin etc. instead of a transparent sheet.

For viscosity control, the coating temperature is preferably in the range of 23 to 50 ° C, more preferably in the range of 24 to 40 ° C, and still more preferably in the range of 25 to 37 ° C.
In order to prevent warping of the disk, it is preferable to irradiate the coating film with ultraviolet rays using a pulsed light irradiator (preferably a UV irradiator). The pulse interval is preferably msec or less, and more preferably μsec or less. 1 pulse irradiation light amount is not particularly limited, and is preferably 3 kW / cm ² or less, 2 kW / cm ² or less being more preferred.
The number of times of irradiation is not particularly limited, but is preferably 20 times or less, and more preferably 10 times or less.
In addition, when the adhesive is provided to the bonding surface of a transparent sheet, the said adhesive agent is unnecessary.

Next, a method for recording information on an optical information recording medium and a method for reproducing recorded information will be described.
Information is recorded on the optical information recording medium, for example, as follows.
First, while rotating the optical information recording medium at a constant linear velocity, 350 to 500 nm (preferably 400 to 440 nm) laser light for recording is irradiated from the transparent sheet side (opposite side of the substrate). By this laser light irradiation, the recording layer absorbs the light and the temperature rises locally, causing a physical or chemical change (for example, generation of pits) and changing its optical characteristics. Information is recorded by this change in optical characteristics.

Examples of the laser light source having an oscillation wavelength of 350 to 500 nm include a blue-violet semiconductor laser having an oscillation wavelength in the range of 390 to 415 nm, a blue-violet SHG laser having a central oscillation wavelength of about 430 nm, and the like.
In order to increase the recording density, the numerical aperture (NA) of the objective lens used for the pickup is preferably 0.7 or more, and more preferably 0.80 or more.

  On the other hand, the recorded information is reproduced by rotating the optical information recording medium at the same constant linear velocity as described above, and emitting laser light having a wavelength equal to or less than that of the laser used for recording information from the transparent sheet side. Irradiation can be performed by detecting the reflected light.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these.

(Example 1)
A substrate having a thickness of 1.1 mm was molded by injection molding using a polycarbonate resin (Panlite AD5503) manufactured by Teijin Chemicals Limited. The groove track pitch of the substrate was 320 nm, the half width of the on-groove portion was 160 nm, and the groove depth was 35 nm.

  Using this target (APC) composed of 98.1 parts by mass of Ag, 0.9 parts by mass of Pd, and 1.0 parts by mass of Cu on this substrate, the reflective layer was formed to a thickness of 100 nm by a vacuum film forming method. Filmed. The input power was 2 kW, and the Ar flow rate was 5 sccm.

  On this reflective layer, an interface layer (thickness: several nm) was formed by vacuum deposition using an Al target and a mixed gas of nitrogen gas 5 sccm and argon gas 5 sccm with an input power of 2 kW.

  An organic dye represented by the following chemical formula was dissolved in TFP (2,2,3,3-tetrafluoropropanol) to prepare a solution having an organic dye concentration of 2.5 g / 100 ml. The solution was further irradiated with ultrasonic waves for 2 hours to further dissolve the organic dye, then allowed to stand in an environment of 23 ° C. and 50% for 0.5 hours or more, and filtered through a 0.2 μm filter. A recording layer having a thickness of 140 nm was formed on the interface layer by spin coating using the filtered solution.

After forming the recording layer, it was heat-treated in a clean oven at 80 ° C. for 1 h. After the heat treatment, a barrier layer having a thickness of 5 nm was formed by a vacuum film forming method using a target composed of 7 parts by mass of ZnO and ₃ parts by mass of Ga ₂ O ₃ . An optical information recording medium was prepared by laminating an 80 μm thick polycarbonate film coated with an adhesive on the barrier layer. In addition, the thickness of the adhesion layer which consists of an adhesive after bonding was 20 micrometers.

(Example 2)
An optical information recording medium was produced in the same manner as in Example 1 except that the nitrogen flow rate for forming the interface layer was set to 6.5 sccm.

(Example 3)
An optical information recording medium was produced in the same manner as in Example 1 except that the reflective layer was formed using a target composed of Ag: 98 parts by mass, Au: 1 part by mass, and Ge: 1 part by mass.

(Comparative Example 1)
An optical information recording medium was produced in the same manner as in Example 1 except that the interface layer was not formed.

(Comparative Example 2)
An optical information recording medium was produced in the same manner as in Comparative Example 1 except that Au was used as the material constituting the reflective layer.

(Comparative Example 3)
An optical information recording medium was produced in the same manner as in Comparative Example 1 except that Al was used as the material constituting the reflective layer.

(Comparative Example 4)
An optical information recording medium was produced in the same manner as in Comparative Example 1 except that Ge was used as the material constituting the reflective layer.

(Comparative Example 5)
An optical information recording medium was produced in the same manner as in Example 1 except that the interface layer was provided on the opposite side of the reflective layer with the recording layer interposed therebetween.
Specifically, the reflective layer and the recording layer were formed in this order on the substrate in the same manner as in Example 1, and then heat-treated in a clean oven at 80 ° C. for 1 h.
On this recording layer, an interface layer was formed by a vacuum film formation method using an Al target and a mixed gas of nitrogen gas 5 sccm and argon gas 5 sccm at an input power of 2 kW.
Thereafter, a polycarbonate film was bonded in the same manner as in Example 1 to produce an optical information recording medium.

Jitter and reflectance measurements were performed on the optical information recording media produced in Examples 1 to 3 and Comparative Examples 1 to 5. Specifically, each optical information recording medium is set in DDU-1000 (manufactured by Pulstec Industrial Co., Ltd.) equipped with a laser optical system having a wavelength of 403 nm and NA = 0.85, and the reflectance at the time of unrecording is set. The jitter was evaluated by recording and reproducing a random signal (2T to 8T) modulated with 1-7 modulation at a power of 5.5 mW. At this time, the linear velocity was 5.28 m / s, and the laser emission pattern during recording was optimized. Jitter was measured using a conventional equalizer.
Further, in the optical information recording media of Examples 1 to 3 and Comparative Example 5 in which the interface layer is formed, immediately after the interface layer is formed, the atomic ratio of N and Al constituting the interface layer is determined by ESCA as N1S. And measured from the peak intensity of Al2S. Specific measurement conditions are shown below. The measurement results are shown in Table 1 below. In Table 1 below, “O” in the jitter column indicates that the jitter is 10% or less, and “X” indicates that it exceeds 10%. Further, “◯” in the reflectance column indicates that the reflectance is 25% or less, and “x” indicates that it exceeds 25%.

(1) ESCA: Shimadzu Corporation AXIS-ULTRA,
(2) X-ray: mono-Al, 12 Kw, 10 mA,
Slit = 45.5, iris = 0.5, PassEnergy = 40 eV,
(3) N1S peak: 410 eV to 385 eV, accumulated 8 times,
(4) Al2S peak: 136 eV to 104 eV Total 8 times, including the chemical shift.
After smoothing each peak to remove noise, atm% was calculated from the peak area.

  In all of the optical information recording media of Comparative Examples 1 to 5, the reflectance could not be within the standard while maintaining good jitter. In contrast, in the optical information recording media of Examples 1 to 3 having the reflective layer, the interface layer, and the recording layer in this order on the substrate, the reflectance can be 25% or less while keeping the jitter low. It was.

Claims (4)

An optical information recording medium comprising at least a reflective layer and a recording layer in this order on a substrate,
The recording layer contains an organic dye,
An optical information recording medium comprising an interface layer between the reflective layer and the recording layer.   The optical information recording medium according to claim 1, wherein the reflective layer contains Ag as a main component.   The optical information recording medium according to claim 1, wherein the interface layer contains N and Al.   The optical information recording medium according to claim 3, wherein an atomic ratio (N / Al) of N and Al in the interface layer is 5/95 to 40/60.