JP2003263785A - Optical information recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical information recording medium which has high adhesion properties between respective layers and has stable recording and reproducing characteristics. <P>SOLUTION: The optical information recording medium 10 like a disk has a central hole 24, has a recording layer 16, tacky adhesive layer 20, and cover sheet 22 in this order on a substrate, has a track pitch of 300 to 600 nm and a groove depth of 40 to 150 nm and is recorded and reproduced with information by being irradiated with a laser beam of a wavelength below 500 nm, in which the substrate and the cover sheet are firmly stuck in the regions of at least portions near the inner periphery and/or the outer periphery with tacky adhesive layer and the maximum value of the diametral direction length of the firmly stuck regions is ≥0.4 mm. <P>COPYRIGHT: (C)2003,JPO

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording medium.
In particular, it relates to write-once optical information recording media using heat mode.
To do. Conventionally, a laser beam is used only once.
An optical information recording medium (optical disc) capable of recording information is known.
It has been. This optical disc is a recordable CD (so-called CD).
-R), the typical structure of which is a transparent disk
Recording layer made of organic dye on substrate, made of metal such as gold
The reflective layer and the resin protective layer (cover layer) are in this order.
Laminated. And record the information on this CD-R
Recording is a laser beam in the near infrared region (usually a wave around 780 nm).
Performed by irradiating CD-R with a long laser beam)
The irradiated part of the recording layer absorbs the light and the temperature locally
Rising, physical or chemical changes (eg pits
The optical properties of the part change
Information is recorded. On the other hand, reading (playback) of information
Also, a laser beam with the same wavelength as the recording laser beam is used for CD.
-R is irradiated to irradiate the optical properties of the recording layer
The part that changed (recorded part) and the part that did not change (not yet)
By detecting the difference in reflectance from the recorded part)
It is. In recent years, an optical information recording medium having a higher recording density.
Is required. In response to such requests, write-once data
Digital Versatile Disc (so-called DVD-R)
Optical discs have been proposed (for example, “Japanese
"New media" separate volume "DVD", 1995
line). This DVD-R is a laser beam to be irradiated.
CD-R is the guide groove for pre-groove
Shape with a narrow groove width of less than half (0.74-0.8μm)
Usually contains organic pigments on a transparent disc-shaped substrate
A recording layer, a reflective layer, and a protective layer were laminated in this order.
A structure in which two discs are bonded with the recording layer inside,
Or a disc-shaped protective substrate with the same shape as this disc
It has a structure in which the recording layer is bonded inside. So
Recording and playback of information on this DVD-R is possible
Visible laser light (usually in the range of 630 nm to 680 nm
Of laser light)
Therefore, recording with a higher density than CD-R is possible. Recently, a network such as the Internet,
High-definition TV is rapidly spreading. HDT
V (High Definition Televis
ion) will start to air soon. like this
It is possible to record image information easily and inexpensively under certain circumstances.
There is a need for large-capacity optical information recording media. DVD
-R plays a role as a large capacity recording medium at present
However, the demand for higher capacity and higher density is increasing.
Of optical information recording media that can meet these requirements.
Development is also necessary. For this reason, it is even shorter than DVD-R.
Higher density recording with wavelength light
Development of an optical information recording medium having a capacity is underway. For example, a high NA lens suitable for high density recording
As a premise for recording with light through
The spray layer, recording layer, and cover layer thinner than the base are provided in this order.
In addition, a recording medium is disclosed, and optical recording is performed from the recording layer side.
Laser on the short wavelength side with a wavelength of 550 nm or less toward the injection layer side
Recording to record information by irradiating light
A recording / playback method is disclosed. And such a short wave
Recording layer forming dye of optical information recording medium using laser beam of
As porphyrin compounds, azo dyes, metal azo colors
Element, quinophthalone dye, trimethine cyanine dye, di
Cyanovinylphenyl skeleton dye and coumarin compound
Etc. have been proposed (for example, Japanese Patent Laid-Open No. 4-74690)
News, 7-304256 Publicity, 7-304257
Public information, 8-1271705 gazette, 11-53758.
Publication No. 11-334204 Publication No. 11-334
No. 205, No. 11-334206, No. 11-
No. 334207, JP-A 2000-43423
No. 2000-108513, 2000-1
49320 publication, 2000-158818 publication,
Publicity No. 2000-228028 and No. 2001-1
46074 public information). Other than these compounds
If it is a compound that can absorb laser light used for recording
In principle, it can be used as a recording layer dye
Can be easily recalled by those skilled in the art. So
As a recording / reproducing laser beam, blue-violet (wavelength 4) is used.
05nm or 410nm), blue (wavelength 430nm)
Or 488 nm) or blue-green (wavelength 515 nm)
Has been proposed. Recording of information with the above short-wave laser beam
A reproducible optical information recording medium is generally provided on a substrate as an example.
For example, reflective layer, recording layer, barrier layer, pressure-sensitive adhesive layer or adhesive
Layer and cover sheet in this order, CD-R and DV
The layer configuration is different from that of D-R. Therefore, the laser light illumination
The shooting direction is the opposite of CD-R and DVD-R, and CD-R
And peeling of the layer that was not a problem with DVD-R
And high adhesion between the layers is required. Shi
However, organic matter (recording layer, etc.) and inorganic matter (reflection layer, barrier layer)
Etc.), the interface is easy to peel
Because it exists, sufficient bonding strength cannot be obtained
There was room for improvement. The present invention is based on the above-described conventional technique.
This was made in view of the problems of
Making it a task. That is, the object of the present invention is to provide each layer
Optical information with high adhesiveness and stable recording / reproduction characteristics
It is to provide a recording medium. Means for Solving the Problems Means for Solving the Problems
Is as follows. That is, on the substrate, the recording layer, the adhesive
Layer or adhesive layer and cover sheet in this order,
Rack pitch is 250-400 nm, groove depth is 10-1
Irradiate laser light with a wavelength of 50 nm or less and 500 nm or less
Disc-shaped with a central hole for recording and reproducing information
An optical information recording medium comprising the substrate and the cover sheet
And through the pressure-sensitive adhesive layer or the adhesive layer,
In at least some areas near the side and / or the perimeter
The maximum value in the radial direction of the contact area is 0.4 m.
The optical information recording medium is characterized by being m or more. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, an optical information recording medium of the present invention will be described.
Embodiments will be described. Optical information recording medium of the present invention
On the substrate, if necessary, reflective layer, recording layer, if necessary
And barrier layer, pressure-sensitive adhesive layer or adhesive layer, and cover sheet
In this order, the track pitch is 250 to 400n
m, the groove depth is 10 to 150 nm and 500 nm or less.
Center to record / reproduce information by irradiating laser light of wavelength
A disc-shaped optical information recording medium having holes, the base
The plate and the cover sheet are the adhesive layer or the contact layer.
Less in the vicinity of the inner periphery and / or the vicinity of the outer periphery through the adhesive layer
In close contact with a part of the region, and the diameter of the contact region
The maximum direction length is 0.4mm or more.
Yes. FIG. 1 and FIG. 2 respectively apply the present invention.
FIG. 3 is a top view and schematic cross-sectional view showing an example of an optical information recording medium.
The The optical information recording medium 10 has a reflective layer 1 on a substrate 12.
4, the recording layer 16, the barrier layer 18, the adhesive layer 20, and the cartridge
It has a bar sheet 22 in this order, with a central hole in the center
24. The optical information recording medium 10 is the same as that shown in FIG.
4 points each near the outer periphery and inner periphery
Substrate (hereinafter referred to as “adhesion region”)
12 and the cover sheet 22 are in close contact with each other through the adhesive layer 20
doing. These are provided near the inner periphery and the outer periphery.
The maximum radial length of each of the four contact areas is 0.5 m.
m. And, by the presence of these adhesion areas,
12, a reflective layer 14, a recording layer 16, and a barrier layer 18
However, it is firmly attached. Therefore, the optical information recording medium 1
Peeling of each layer of 0 can be prevented. In FIG.
In this case, four close contact areas are provided on the outer periphery and the inner periphery, respectively.
However, the present invention is not limited to this.
Yes. A large number of close contact areas should be provided, or the outer periphery and the inner
It is preferable to provide the entire circumference. In the present invention, the radial direction of the contact area
The maximum value of the length is 0.4 mm or more, but the maximum value is
If the thickness is less than 0.4 mm, the adhesion force is insufficient and peeling of the layer occurs.
There is a case. More specifically, the maximum value is near the outer periphery.
Is more preferably 0.6 mm or more.
More preferably, it is 0.7 mm or more. Also near the outer periphery
The upper limit of the maximum value in is 2 mm. Also near the inner circumference
The maximum value of the radial length of the close contact area at the side is 2.5 mm
More preferably, 3 mm or more is more preferable, 4
Particularly preferred is mm or more. In addition, the maximum in the vicinity of the inner periphery
The upper limit of the large value is 15 mm. In the optical information recording medium of this embodiment, the inner circumference and the
And a form having a close contact area on the outer periphery.
Although it is preferable, a close contact region is provided on either the inner periphery or the outer periphery.
It may be formed. The substrate and optical information recording medium of the present invention will be described below.
Each layer will be described in detail. <Substrate> As a substrate, a substrate material of a conventional optical information recording medium
Select and use various materials used as materials.
Can be used. Specifically, glass; polycarbonate
Acrylic resins such as nates and polymethyl methacrylate;
Vinyl chlorides such as polyvinyl chloride and vinyl chloride copolymers
Resin; epoxy resin; amorphous polyolefin;
Reesters; metals such as aluminum;
These may be used together if desired. Of the above materials
In terms of moisture resistance, dimensional stability and low price,
Polycarbonate and amorphous polyolefin are preferred
Polycarbonate is particularly preferred. Also the board
The thickness is preferably 0.5 to 1.4 mm. On the substrate, a guide groove for tracking or
Concavities and convexities (pre-grooves) representing information such as address signals
Is formed. C to achieve higher recording density
Narrower track pitch than D-R and DVD-R
It is preferable to use a substrate with a pregroove of
Yes. Pregroove track pitch is 250-400
nm. The pregroove depth (groove depth) is
10 to 150 nm, preferably 15 to 10 nm.
0 nm, more preferably 20 to 80 nm
Most preferably, it is 20-60 nm. It should be noted that the base on the side where the reflection layer described later is provided.
For the purpose of improving the flatness and adhesion,
It is preferable to form a coating layer. As a material for the primer layer
For example, polymethyl methacrylate, acrylic acid
Methacrylic acid copolymer, styrene / maleic anhydride copolymer
Coalescence, polyvinyl alcohol, N-methylol acrylic
Amides, styrene-vinyltoluene copolymers, chlors
Rufonated polyethylene, nitrocellulose, polyvinyl chloride
Nyl, chlorinated polyolefin, polyester, polyimi
, Vinyl acetate / vinyl chloride copolymer, ethylene / acetic acid
Vinyl copolymer, polyethylene, polypropylene, poly
Polymeric substances such as carbonates; Silane coupling agents, etc.
And surface modifiers. Undercoat layer
Prepare a coating solution by dissolving or dispersing the material in a suitable solvent.
After that, this coating solution is applied by spin coating, dip coating,
Apply to the surface of the substrate by a coating method such as crushing coat
It can be formed by clothing. Undercoat layer thickness
Is generally in the range of 0.005-20 μm and is preferred
Or in the range of 0.01 to 10 μm. <Reflective layer> The reflective layer is for laser light.
A light reflective material having a high reflectance is used. The reflectance
As 70% or more. Reflective material with high reflectivity
As the quality, Mg, Se, Y, Ti, Zr, Hf, V,
Nb, Ta, Cr, Mo, W, Mn, Re, Fe, C
o, Ni, Ru, Rh, Pd, Ir, Pt, Cu, A
g, Au, Zn, Cd, Al, Ga, In, Si, G
e, Te, Pb, Po, Sn, Bi and other metals and metal
Genus or stainless steel. these
These light-reflective materials may be used alone or in combination of two
You may use it in the above combination or as an alloy. this
Among these, preferred are Cr, Ni, Pt, Cu,
Ag, Au, Al and stainless steel. Especially preferred
Or Au, Ag, Al or alloys thereof.
Most preferably, Au, Ag or an alloy thereof
It is. The reflective layer is formed by vapor-depositing the light reflecting material described above.
Sputtering or ion plating
More can be formed on the substrate. The thickness of the reflective layer is
Generally, the range is 10 to 300 nm, and 50 to 200.
A range of nm is preferable. Also, check the contact area.
In order to preserve the area where the reflective layer is not formed using a mask
Establish a zone. The above reflective layers have the following recording layer reflectivities:
If it is large enough, it is not always necessary.
The recording layer serves as a reflective layer. <Recording layer> The recording layer contains a dye compound.
As the dye compound, a triazole compound
Products, phthalocyanine compounds, porphyrin compounds, a
These include minobutadiene compounds and cyanine compounds.
Is preferably at least one of phthalocyanines
Examples of compounds include alkoxy-substituted products, sulfonamides
Substituted, sulfomoyl substituted, sulfonic acid substituted
It is preferable that it is at least one of the above. Japanese Patent Laid-Open No. 4-74690, Japanese Patent Laid-Open No. 4-74690
No. 8-127174, No. 11-53758
No. 11-334204, 11-33420
No. 5, No. 11-334206, No. 11-33
No. 4207, Japanese Patent Laid-Open No. 2000-43423, the same
No. 2000-108513 and 2000-1
In combination with dyes described in Japanese Patent No. 58818
You can. Furthermore, it is not limited to the above dyes,
Sol compounds, triazine compounds, cyanine compounds,
Russianin compounds, aminobutadiene compounds, phthalos
Anine compound, cinnamic acid compound, viologen compound, azo
Compound, oxonol benzoxazole compound, ben
Organic compounds such as zotriazole derivatives are also preferably used.
The Among these compounds, benzotriazole derivatives
And phthalocyanine compounds are particularly preferred. The recording layer records the above dyes (organic substances, etc.)
Dissolve the substance in a suitable solvent together with a binder, etc.
Prepare the cloth liquid, and then apply this recording layer coating liquid on the substrate surface.
On the formed reflective layer (or on the substrate if no reflective layer is provided)
Formed by applying and forming a coating and then drying.
It is. And, in order to provide a close contact area, after application, the area
Rinse away with solvent. Recorded matter in the recording layer coating solution
The quality concentration is generally in the range of 0.01-15% by weight.
Preferably in the range of 0.1-10% by weight, more preferred
Or 0.5 to 5% by mass, most preferably 0.5 to
The range is 3% by mass. In addition, the recording materials etc. are dissolved.
Examples of methods that can be used include sonication, homogenizer, and heating.
The method can be applied. As a solvent for preparing the recording layer coating solution
Butyl acetate, methyl lactate, ethyl lactate, cellosolve
Esters such as acetate; methyl ethyl ketone, cyclo
Ketones such as hexanone and methyl isobutyl ketone;
Lormethane, 1,2-dichloroethane, chloroform, etc.
Chlorinated hydrocarbons; amides such as dimethylformamide;
Hydrocarbons such as methylcyclohexane; Tetrahydrofura
Ethers such as ethylene, ethyl ether and dioxane;
N-propanol, isopropanol, n-butane
Alcohols such as nordiacetone alcohol; 2,2,
Fluorine-based solution such as 3,3-tetrafluoropropanol
Agent; ethylene glycol monomethyl ether, ethylene
Glycol monoethyl ether, propylene glycol
Glycol ethers such as monomethyl ether;
I can make it. The above-mentioned solvent considers the solubility of the recording material used.
Use alone or in combination of two or more
Can. In the coating solution, further antioxidants, UV
Depending on the purpose, various additives such as absorbents, plasticizers, lubricants, etc.
It may be added. As an example of a binder when a binder is used.
Gelatin, cellulose derivatives, dextran,
Natural organic polymer materials such as gin and rubber; polyethylene,
Charcoal such as polypropylene, polystyrene and polyisobutylene
Hydrogen fluoride resin; polyvinyl chloride, polyvinylidene chloride,
Vinyl type such as polyvinyl chloride / polyvinyl acetate copolymer
Resin; Polymethyl acrylate, Polymethyl methacrylate
Acrylic resin such as polyvinyl alcohol, chlorinated poly
Ethylene, epoxy resin, butyral resin, rubber induction
Body, phenolic / formaldehyde resin, etc.
Synthetic organic polymers such as precondensates of fats;
it can. When using a binder as a material for the recording layer,
The amount of binder used is generally 0.01 times the recording material.
The amount is in the range of 50 to 50 times (mass ratio), preferably 0.
It is in the range of 1 to 5 times the amount (mass ratio). In this way
The concentration of the recording substance in the coating solution produced is generally 0.01.
In the range of -10% by weight, preferably 0.1-5% by weight.
% Range. As the coating method, spray method, spin coating
Coating method, dipping method, roll coating method, blade coating
Mention the law, doctor roll method, screen printing method, etc.
You can. The recording layer may be a single layer or a multilayer. In addition,
The thickness of the recording layer is generally in the range of 20 to 500 nm,
Preferably it is in the range of 30-300 nm, more preferred
Or in the range of 50 to 100 nm. Also, the application temperature and
As long as it is 23 to 50 ° C, there is no particular problem, but it is preferable.
Or 24 to 40 ° C, more preferably 25 to 37 ° C.
is there. The coating temperature is 23 to 50 ° C. for viscosity control.
Is preferable, and a range of 24 to 40 ° C. is more preferable.
Further, the range of 25 to 37 ° C is more preferable. Disc
In order to prevent warping, UV irradiation to the coating film is pulsed
Using a mold type light irradiator (preferably UV irradiator)
Is preferred. The pulse interval is preferably less than msec,
More preferably not more than μsec. The amount of light emitted per pulse is special.
Is not limited to 3 kW / cm ² Preferred is 2
kW / cm ² The following is more preferable. In addition, the number of irradiations is special.
Although it is not limited to, 20 times or less is preferable and 10 times or less
Is more preferable. The recording layer improves the light resistance of the recording layer.
In order to contain various antifading agents
The In general, singlet oxygen quenching is used as an anti-fading agent.
Is used. As a singlet oxygen quencher,
Use those described in publications such as already known patent specifications.
Can. Specific examples thereof include Japanese Patent Laid-Open No. 58-1.
75693, 59-81194, 60
No. 18387, No. 60-19586, No. 6
No. 0-19587, No. 60-35054, No.
60-36190, 60-36191,
No. 60-44554, No. 60-44555
No. 60-43389, 60-44390
Gazette, 60-54892 gazette, 60-47069
Gazettes, 63-209995 gazettes, Japanese Patent Laid-Open No. 4-25
No. 492, JP-B-1-38680, and the like
Japanese Patent Publication No. 6-26028, German Patent 3503
No. 99 specification, and the October 1992 issue of the Chemical Society of Japan
The thing as described in page 1141 etc. can be mentioned. Prevention of fading such as the singlet oxygen quencher
The amount of agent used is generally the amount of compound to be recorded.
It is usually in the range of 0.1 to 50% by mass, preferably
The range of 5 to 45% by mass, more preferably 3 to 40% by mass.
%, Particularly preferably in the range of 5 to 25% by weight.
The <Barrier layer> The barrier layer includes the recording layer and the back layer.
Formed as needed between the adhesive layer or adhesive layer to be described
Is the layer to be played. As a material constituting the barrier layer,
As long as it is a material that transmits user light, there is no particular limitation.
A dielectric is preferable, and more specifically, Zn
S, TiO ₂ , SiO ₂ ZnS-SiO ₂ , GeO ₂ , S
i _Three N _Four , Ge _Three N _Four , MgF ₂ Inorganic oxide, nitriding, etc.
And sulfides, ZnS-SiO ₂ Or S
iO ₂ Is preferred. The barrier layer is made of sputtering,
Can be formed by plating, etc.
The thickness is preferably 1 to 100 nm. Also dense
Use a mask to form the barrier layer to secure the contact area.
An area that is not formed is provided. In the optical information recording medium of the present invention,
On the recording layer or barrier layer, a cover sheet to be described later is
Bonded via the pressure-sensitive adhesive layer or adhesive layer shown below
It is. <Adhesive layer> The adhesive layer is a cover described later.
It is a layer that is formed to bond sheets, and is well known in the past
Can be widely used. As an adhesive,
Acrylic adhesive, natural rubber, styrene-isoprene
-Styrene copolymer (SIS), styrene-butadiene
-Adopt rubber adhesive such as styrene copolymer (SBS) as appropriate
It can be selected and used. The adhesive is a cover sheet.
It is preferable that it is applied in advance to the bonding surface of the sheet
Yes. The thickness of the pressure-sensitive adhesive layer is 1 to 10 μm, particularly preferably 2
The range is ˜5 μm. <Adhesive layer> The adhesive layer is the same as the adhesive layer.
Is formed to adhere a cover sheet to be described later
Is a layer. As a material constituting the adhesive layer, photo-curing
Resin, two-component curable adhesive, etc.
In order to prevent the disc from warping.
Those having a small shrinkage ratio are preferred. Such photo-curing
As resin, for example, Dainippon Ink & Chemicals, Inc.
“SD-640”, “SD-661”, “SD-34”
7 ”and other UV curable resins (UV curable adhesives)
be able to. Also, the thickness of the adhesive layer has elasticity
Therefore, the range of 1-1000 μm is preferable, and 5-5
The range of 00 μm is more preferable, and the range of 10 to 100 μm.
An enclosure is particularly preferred. Other examples of materials for forming the adhesive layer
The The material is a resin curable by irradiation.
And having two or more radiation-functional double bonds in the molecule
Acrylic esters, acrylamide
Methacrylic acid esters, methacrylic acid amides,
Allyl compounds, vinyl ethers, vinyl esters
I can give it. Preferably bifunctional or higher acrylate
Compounds and methacrylate compounds. Specific examples of the bifunctional group include ethylene glycol
Diacrylate, propylene glycol diacrylate
, Butanediol diacrylate, hexanediol
Rudiacrylate, diethylene glycol diacryl
, Triethylene glycol diacrylate, tetrae
Tylene glycol diacrylate, neopentyl glyco
Diacrylate, tripropylene glycol diac
Relate, ethylene glycol dimethacrylate, pro
Pyrene glycol dimethacrylate, butanediol di
Methacrylate, hexanediol dimethacrylate,
Diethylene glycol dimethacrylate, triethylene
Glycol dimethacrylate, tetraethyleneglycol
Rudimethacrylate, neopentylglycol dimethac
Relate, tripropylene glycol dimethacrylate
Acrylic acid and methacrylate
What added rilic acid can be used. In addition, polyethylene glycol, polypro
Pyrene glycol, polytetramethylene glycol, etc.
Polyether polyol with acrylic acid and methacrylic acid
Added polyether acrylate, polyether
Obtained from tacrylate, known dibasic acid, glycol
Polyester polyol with acrylic acid and methacrylic acid
Added polyester acrylate, polyester
Methacrylate can also be used. In addition, known
Reaction of polyol, diol and polyisocyanate
Add acrylic acid or methacrylic acid to the polyurethane
Polyurethane acrylate, polyurethane methacrylate
You may also use a cart. In addition, bisphenol A, bisphenol
F, hydrogenated bisphenol A, hydrogenated bisphenol F
And these alkylene oxide adducts with acrylic acid,
Methacrylic acid added or isocyanuric acid alkyl
Ren oxide modified diacrylate, isocyanuric acid
Lucylene oxide modified dimethacrylate, trisic
Rhodecane dimethanol diacrylate, tricyclodeca
Has a cyclic structure such as dimethylethanol dimethacrylate
Can also be used. Examples of the radiation include electron beams and ultraviolet rays.
Can be used. When using ultraviolet light
It is necessary to add a photoinitiator to the compound below.
The An aromatic ketone is used as a photopolymerization initiator. Good
The aromatic ketone is not particularly limited, but an ultraviolet irradiation light source and
Thus, the emission line spectrum of a normally used mercury lamp is generated.
Of the extinction coefficient at wavelengths of 254, 313 and 865 nm.
A comparatively large thing is preferable. A typical example is a
Cetophenone, benzophenone, benzoin ethyl acetate
Tellurium, benzyl methyl ketal, benzyl ethyl keter
, Benzoin isobutyl ketone, hydroxydimethyl
Phenyl ketone, 1-hydroxycyclohexyl phenyl
Luketone, 2-2 diethoxyacetophenone, Mich
ler's ketone, and various aromatic ketones are used.
Can be used. The mixing ratio of the aromatic ketone is compound (a) 1
0.5 to 20 parts by mass, preferably 2 to 100 parts by mass
It is 15 mass parts, More preferably, it is 3-10 mass parts.
Add photoinitiator as UV curable adhesive in advance
It is commercially available and may be used.
A mercury lamp is used as the ultraviolet light source. Mercury lamp is 2
Using a 0-200 W / cm lamp, speed 0.3 m / min
Used at 20 m / min. The distance between the base and mercury lamp is general
It is preferable that it is 1-30 cm. As an electron beam accelerator, a scanning method,
Double scanning method or curtain beam method
Although it can be used, it is preferable that it is relatively inexpensive and provides a large output.
The curtain beam method. As electron beam characteristics,
Accelerating voltage is 100 to 1000 kV, preferably 150 to
300kV, absorbed dose 0.5 ~ 20Mra
d, preferably 1 to 10 Mrad. Acceleration voltage is 1
In the case of 0 kV or less, the amount of transmitted energy is insufficient and 10
If it exceeds 00 kV, the energy efficiency used for polymerization is low.
This is not preferable in terms of cost. <Cover sheet> A cover sheet is formed.
The material is not particularly limited as long as it is a transparent material.
However, the material is polycarbonate, cellulose triacetate
It is preferable to be an acrylic polymer. Also,
The material has a moisture absorption of 5% or less at 23 ° C and 50% RH.
And are preferred. Furthermore, the cover sheet has a surface roughness of 5n.
m or less, birefringence of 10 nm or less
It is preferable that “Transparent” means recording and playback
Transmits the light to the laser beam (transmittance: 8
0% or more). Cover
The thickness of the sheet is preferably in the range of 0.01 to 0.2 mm
More preferably, in the range of 0.03-0.1 mm
More preferably 0.05 to 0.095 mm.
It is a circle. A cover sheet is formed using the pressure-sensitive adhesive layer.
As a method of pasting on the recording layer or barrier layer, cover
After applying the adhesive on the sheet and drying the solvent,
Roll the cover sheet on the intermediate layer through the adhesive
Applying pressure to attach the cover sheet
Can be mentioned. As the application temperature of the adhesive, the viscosity was controlled.
Therefore, it is preferably in the range of 23 to 50 ° C,
More preferably in the range of 40 ° C, 25-37 ° C.
More preferably, it is the range. After application, preferably
Is 50 to 300 ° C., more preferably 80 to 200 ° C.
Preferably, it is dried at 100 to 150 ° C. Also,
The temperature at which the bar sheet is bonded is 0-10.
Preferably in the range of 0 ° C, in the range of 15-50 ° C
It is more preferable that In addition, it has releasability for the adhesive used.
The adhesive was applied on the released release film and the solvent was dried.
After that, a cover sheet is attached, and a release film
After peeling off and providing an adhesive on the cover sheet, record
By covering the layers or barrier layers together,
It is also possible to attach a sheet. In particular, contained in the adhesive
This method is desirable when the solvent dissolves the cover sheet.
That's right. A sheet provided with an adhesive layer on a release film.
When using a sheet, the film used as the base material
If the solvent is insoluble in the solvent contained in the adhesive,
For example, polyethylene terephthalate
Plastic, polypropylene, polyethylene, vinyl chloride, etc.
Plastic film, kraft paper, fine paper, Creco
Non-woven paper such as cardboard, Japanese paper, rayon, polyester, etc.
Synthetic fibers such as cloth, polyester, nylon and acrylic
Metal such as woven cloth, aluminum, copper, stainless steel
A foil is used, but the release agent layer is continuously thinned on the film.
And plastic film is preferable from the viewpoint of uniform application.
Good. Moreover, as a mold release agent to be used, silicone
It has been used in the past such as long-chain release agents and long-chain alkyl release agents
Various releasing agents can be appropriately selected and used. EXAMPLES Examples of the present invention will be described in detail below.
However, the present invention is not limited to this. Example 1 Thickness 1.1 mm, outer diameter 120
mm, 15 mm inner diameter spiral groove (track
Crop pitch: 340 nm, groove depth: 30 nm, groove width: 15
nm) of injection molded polycarbonate resin substrate
On the surface with the lube, use Unaxis Cube
In the Ar atmosphere, Ag is sputtered to 120 nm
A reflective layer having a layer thickness was formed. During this sputtering, the contact area
In order to secure the area, a mask is used.
The reflective layer is not formed in the area near the inner periphery and the outer periphery.
I tried to avoid it. Next, dye A2g represented by the following structural formula
2,2,3,3-tetrafluoropropanol 100
A dye coating solution was prepared by dissolving in ml. This dye coating solution
Apply uniformly to the substrate by spin coating, and the thickness in the groove
A recording layer having a thickness of 100 nm and a land portion thickness of 70 nm is formed.
It was. Then, the inner and outer sides where the reflective layer is not formed
A part of the circumference was washed away and removed. Next, clean
Annealing was performed at 40 ° C. for 1 hour. this
The substrate is spaced by a spacer on the vertical stack pole.
We supported in the state. Embedded image After annealing, ZnS-SiO ₂ (8: 2)
By RF sputtering to a thickness of 50 nm.
Sputter power 4kW, pressure 2 × 10 ^-2 hPa, 1
Sputtering was performed under the condition of 0 seconds to form a barrier layer. this
When using the mask used in forming the reflective layer, the inner and outer circumferences
The barrier layer was not formed in a part of the region. An adhesive was applied to the surface with a thickness of 15 μm.
Polycarbonate cover sheet (Teijin Puree
Base, thickness: 85 μm)
The substrates were pasted together in a state in which they were matched. Outer and inner circumference
In this case, the substrate and the cover sheet are
The maximum radial length of the attached contact area is 0.5 mm.
It was. The optical information recording medium of Example 1 is obtained through the above steps.
It was. (Comparative Example 1) In Example 1, the reflective layer
Same as Example 1 except that the entire surface was formed up to the edge of the substrate.
Thus, an optical information recording medium of Comparative Example 1 was obtained. (Comparative Example 2) In Example 1, the recording layer
Same as Example 1 except that the entire surface was formed up to the edge of the substrate.
Thus, an optical information recording medium of Comparative Example 2 was obtained. Comparative Example 3 In Example 1, the barrier layer
Example 1 except that the entire surface of the substrate was formed up to the edge of the substrate.
Similarly, an optical information recording medium of Comparative Example 3 was obtained. Comparative Example 4 In Example 1, the pressure-sensitive adhesive layer
The diameter of the contact area where the substrate and cover sheet are in close contact with each other
Similar to Example 1, except that the direction length is 0.1 mm
Thus, an optical information recording medium of Comparative Example 4 was obtained. [Evaluation] Obtained in Example 1 and Comparative Examples 1 to 4.
The following (1) peel test on the optical information recording medium,
(2) Drop test and (3) Evaluation of recording characteristics
It was. (1) Peeling test The gum on the surface of the obtained optical information recording medium on the cover sheet side
A test is applied to the tape and peeled off.
Therefore, it evaluated. The results are shown in Table 1. [Evaluation criteria] ○: No peeling occurred. X: Peeling occurred. (2) Drop test The test was dropped 20 times on a concrete floor from a height of 1 m.
Observe the peeling of the outer edge of the board, and according to the following evaluation criteria
evaluated. The results are shown in Table 1. [Evaluation Criteria] A: Peeling of the outer edge of the substrate was hardly observed. B: Peeling of the outer edge of the substrate was observed. (3) Evaluation of recording characteristics DDU1000 (manufactured by Pulse Tech Co., Ltd.)
Recorded at 4.9 m / s and pit length of 160 nm.
(1) C / N before and after the peel test was measured. Measurement results
Table 1 shows. [Table 1] From Table 1, the optical information recording medium of Example 1 is
(1) Peel test (2) Drop test, and (3)
From the results of recording characteristics evaluation, it has high adhesion,
It can be seen that it has high recording characteristics. According to the present invention, the adhesion between each layer is high.
Optical information recording media with stable recording and playback characteristics
can do.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view showing an optical information recording medium to which the present invention is applied. FIG. 2 is a diagram schematically showing a cross section taken along line II-II in FIG. 1; [Explanation of Symbols] 10 Optical Information Recording Medium 12 Substrate 14 Reflective Layer 16 Recording Layer 18 Barrier Layer 20 Adhesive Layer 22 Cover Sheet 24 Center Hole

Claims (1)

What is claimed is: 1. A substrate having a recording layer, a pressure-sensitive adhesive layer or an adhesive layer, and a cover sheet in this order, having a track pitch of 250 to 400 nm and a groove depth of 10 to 150 nm. ,
A disk-shaped optical information recording medium having a central hole for recording and reproducing information by irradiating a laser beam having a wavelength of 500 nm or less, wherein the substrate and the cover sheet are the pressure-sensitive adhesive layer or the adhesive layer. The optical information recording medium is characterized in that it is in close contact in the vicinity of the inner periphery and / or in the vicinity of the outer periphery, and the maximum radial length of the contact region is 0.4 mm or more.