JP2009004031A - Recording device of optical recording medium and preparing system of optical recording medium with content recorded thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical recording device capable of controlling a recording condition according to an optical characteristic of an optical recording medium in which Low to High-recording is performed by using a DVD laser wavelength (640 to 680 nm) and to provide a preparing system of a write-once optical recording medium with a content recorded thereon. <P>SOLUTION: (1) The optical recording device can perform recording in the optical recording medium in which Low to High-recording is performed by using a DVD laser wavelength, detects a push-pull signal and/or a wobble frequency of a guide groove from a track error signal and controls recording condition based on the detection results to perform recording. (2) The optical recording device can performs recording in the optical recording medium in which Low to High-recording is performed by using the DVD laser wavelength, detects a push-pull signal and/or a wobble frequency of a guide groove from a track error signal and detects a medium reflectance and/or the number of reflection surfaces from a focus error signal or a reproduction signal and controls a recording condition based on the detection results to perform recording. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is a write-once type optical recording medium (so-called low to high type recording) in which the reflectivity after recording is higher than the reflectivity before recording of the recording mark portion at the DVD laser wavelength (640 to 680 nm). The present invention relates to an optical recording apparatus capable of recording on a low to high write-once recording medium) and a system for creating a content-recordable write-once optical recording medium.

In addition to optical recording media such as a reproduction-only (read-only) DVD (digital versatile disk), recordable DVDs (DVD + RW, DVD + R, DVD-R, DVD-RW, DVD-RAM, etc.) have been put into practical use. These are positioned as an extension of conventional CD-R and CD-RW (recordable compact disc) technologies, and in order to ensure playback compatibility with playback-only DVDs, recording density (track pitch, signal mark length) and The thickness of the substrate is changed from the CD condition to the DVD condition. For example, in DVD + R, as in CD-R, a dye material is spin-coated on a substrate on which guide grooves and / or pits are formed, and an optical recording layer (hereinafter sometimes referred to as “dye recording layer”). A structure is employed in which an information recording substrate provided with a reflective layer behind it is bonded to a substrate of the same shape via a bonding material.
By the way, in the case of CD-R, one of the features is that it has a high reflectance (65%) that satisfies the CD standard (see Patent Document 1). In order to obtain a refractive index, the optical recording layer needs to satisfy a specific complex refractive index at a recording / reproducing light wavelength (≈650 nm). When a dye material is used for the optical recording layer, the light absorption of the dye material There is an advantage that the high reflectance can be realized depending on characteristics. For this reason, a dye material has been used for the optical recording layer in DVD + R as well as CD-R. These optical recording media use the characteristics of the long wavelength end of the light absorption band in the light absorption spectrum of the dye material (see FIG. 1), and the so-called reflectance (the amount of reflected light) decreases after recording. DVD + R media and DVD-R media of the type that perform recording in the High to Low mode have already been commercialized as recording DVD systems.

Japanese Patent Laid-Open No. 2-42652

A conventional High to Low type optical recording medium (High to Low recording medium) has high reflectivity before recording (low light absorption), and therefore has insufficient recording sensitivity particularly during high-speed recording. Also, since the reflectivity after recording is large, the push-pull signal [push-pull (difference signal) / reflectance (sum signal)] after recording tends to be large, and the signal from the guide groove is the data as the noise component. There was a problem that it was easy to mix in the signal.
Therefore, as a result of intensive studies by the present inventors, when a DVD is designed as a Low to High type optical recording medium (Low to High recording medium), recording sensitivity (light absorption rate) is sufficient, and recording at high speed recording is possible. It has been found that the characteristics are excellent and the push-pull signal after recording can be reduced.
Incidentally, when recording on an optical recording medium, the conventional optical recording apparatus first determines the type of the optical recording medium. In general, an optical recording apparatus is an apparatus capable of recording and reproducing a plurality of types of media such as a reproduction-only DVD (DVD-ROM), a write-once DVD (DVD + R or DVD-R), and a rewritable DVD (DVD + RW, DVD-RW or DVD-RAM). In order to implement recording and reproduction, it is necessary to determine the type of the medium in advance in order to correspond to the physical characteristics and recording characteristics of each medium. A write-once DVD and a rewritable DVD employ a method of recording medium type information as guide groove information, and the medium type can be determined by reading this information. Further, when there is no guide groove information, it can be determined as a DVD-ROM.

However, in order to read the guide groove information signal, the groove information must be reproduced with laser light, and there is a problem that reproduction cannot be performed unless reproduction conditions suitable for various media are set.
For example, since the distance to the recording surface is different between a single-layer medium and a two-layer medium, it is necessary to set a laser focus optimized according to the type of the medium. In addition, because optical characteristics such as reflectance are different (reflectance standards are DVD-ROM single layer: 45% or more, DVD-ROM two layers: 18% or more, DVD + R single layer: 45% or more, DVD-R single layer: 45 % +, DVD + RW single layer: 18-30%, DVD + R2 layer: 16% or more, DVD-R2 layer: 16% or more, DVD + RW2 layer: 5-10%), optimal according to the optical characteristics of the medium (type of medium) Servo gain setting is required. This is because in these media, a signal is recorded due to a change in reflectance, and thus the difference in reflectance affects the reproduction signal intensity.
Moreover, since the Low to High recording medium is not an existing medium, the recording apparatus cannot control appropriate recording conditions for the Low to High recording medium unless a new control method is set. In addition, the low-to-high recording medium has a lower reflectance before recording than the existing high-to-low recording medium, and therefore setting of recording conditions different from the high-to-low recording medium (increasing the servo gain) is required. is necessary. Further, it is necessary to reverse the negative / positive of the recording light emission pattern.

  The present invention solves the above-described problems, and enables optical recording that enables control of recording conditions according to the optical characteristics of an optical recording medium on which Low to High recording is performed at a DVD laser wavelength (640 to 680 nm). It is an object of the present invention to provide a device and a system for creating a content-recordable write-once optical recording medium.

The above problems are solved by the following inventions <1> to <8>.
<1> An optical recording apparatus capable of recording on an optical recording medium on which low to high recording is performed at a DVD laser wavelength (640 to 680 nm), and detects a push-pull signal and / or a meandering frequency of a guide groove from a track error signal. An optical recording apparatus that controls and records recording conditions based on the detection results.
<2> When the push-pull signal detection result is less than 0.3 and the detection result of the meandering frequency of the guide groove is “Yes”, the write-once optical recording medium performs Low to High recording. The optical recording apparatus according to <1>, wherein the recording condition is controlled based on the determination result and the recording condition is controlled.
<3> An optical recording apparatus capable of recording on an optical recording medium on which low to high recording is performed at a DVD laser wavelength (640 to 680 nm), and detects a push-pull signal and / or a meandering frequency of a guide groove from a track error signal. In addition, the optical recording apparatus is characterized in that the medium reflectance and / or the number of reflection surfaces are detected from the focus error signal or the reproduction signal, and recording is performed by controlling the recording conditions based on the detection results.
<4> When the detection result of the push-pull signal is less than 0.3, the detection result of the medium reflectance in the unrecorded state is 12 to 30%, and the detection result of the number of reflection surfaces is one surface, The optical recording apparatus according to <3>, wherein the optical recording apparatus is determined to be a write-once type optical recording medium on which Low to High recording is performed, and recording is performed by controlling recording conditions based on the determination result.
<5> The optical recording apparatus according to <2> or <4>, wherein the optical recording apparatus is identified as a write-once type optical recording medium on which Low to High recording is performed and a CSS content recording medium.
<6> Write-once light that controls reproduction conditions based on the controlled recording conditions, and further reads discriminating information relating to a medium recorded as Low to High recorded as a guide groove signal and performs Low to High recording. The optical recording apparatus according to any one of <1> to <5>, wherein the recording is performed after confirming that the recording medium or the CSS content recording medium.
<7> The optical recording apparatus according to any one of <1> to <6>, further comprising means for acquiring content information via a network.
<8><2>,<4>,<5>,<6> Content recording additional recording comprising the optical recording device according to any one of the above, and a server connected to the optical recording device via a network Type optical recording medium creation system, which permits recording of acquired content information when it is determined that it is a write-once optical recording medium on which content information is acquired and Low to High recording is performed A system for creating a write-once type optical recording medium on which content is recorded.

Hereinafter, the present invention will be described in detail.
FIG. 7 is a diagram for explaining the outline of discrimination of the medium type according to the present invention. This shows a flow of obtaining lower discrimination information from the upper servo signal or reproduction signal and obtaining reproduction condition adjustment information from the discrimination information.
In the invention <1>, the push-pull signal and / or the meandering frequency of the guide groove are detected from the track error signal, and recording is performed by controlling the recording conditions based on the detection results.
For example, the push-pull signal of a Low to High write-once recording medium is usually less than 0.3, and the push-pull signal of a general DVD-ROM is 0.3 or less. On the other hand, in DVD + R and DVD + RW, the push-pull signal standard is set to 0.3 to 0.6. Therefore, as in the invention <2>, this difference can be used to discriminate between Low to High write-once recording media and DVD-ROMs, and DVD + R and DVD + RW. Further, since the DVD-ROM does not have a meandering guide groove, the Low to High write-once recording medium and the DVD-ROM can be discriminated by detecting the meandering frequency of the guide groove.

In the invention <3>, the push-pull signal and / or the meandering frequency of the guide groove is detected from the track error signal, the medium reflectance and / or the number of reflection surfaces are detected from the focus error signal or the reproduction signal, and the detection results thereof Based on the above, the recording conditions are controlled and recorded.
As in the invention <1>, it is possible to determine only by information from the track error signal, but information from the focus error signal or the reproduction signal may be combined.
For example, as described above, the reflectance varies depending on the medium type, and this can be used to determine the medium type. Furthermore, by detecting a focus error signal or a reproduction signal that is a reflection signal while changing the depth of focus, it is possible to obtain information on the number of reflection surfaces (discrimination information between a single-layer medium and a two-layer medium).
Further, the guide groove is formed by meandering at a specific frequency in order to obtain a rotation synchronization clock during recording and reproduction. This meandering frequency is set to 818 kHz in the DVD + R standard and 140 kHz in the DVD-R standard, and the medium type can be determined using this difference.

As a result of the above discrimination, the optimum recording / playback conditions (tracking servo, focus servo, etc.) for the medium can be set, so it is possible to reduce servo failures and malfunctions during recording / playback, and to record data due to poor tracking and focusing adjustments. Since there is no deterioration in reproduction quality (jitter increase or data error), excellent recording / reproduction performance can be obtained.
Further, medium information and address information are recorded in advance in the guide groove, and the phase modulation wobble method is adopted in the DVD + R standard and the Lpp (land prepit) method is adopted in the DVD-R standard. The medium type can be easily determined by reading these pieces of information. However, in this case, unlike push-pull signals and meander frequency detection, tracking servo (tracking servo) to the guide groove is required, so reading is difficult unless the playback conditions suitable for the medium are set as described above. It is.

In the invention <4>, the medium reflectance and the number of reflecting surfaces are used for determining the medium type. Since the medium reflectivity in the unrecorded state of the write-once type optical recording medium on which Low to High recording is performed is usually about 12% to 30%, it is determined by combining this with the number of reflecting surfaces.
In the invention <5>, the optical recording apparatus determines that the medium is a Low to High write-once optical recording medium and a CSS content recording medium. This makes it possible to create a highly compatible CSS content recording medium.

  Since DVD can record digital moving images with high image quality for a long time, copyright protection of the content is indispensable. As a method for protecting copyright, for example, CSS (Content Scramble System) is known. This prevents unauthorized copying using consumer devices by general users and unauthorized copying using a computer. The DVD video content encrypted by CSS is normally present only on a read-only DVD disc. As a result, if the playback device identifies the recordable DVD disc and the read-only DVD disc and determines that it is a recordable DVD disc, it is assumed that the copy was made illegally, and the recordable DVD disc is The reproduction of the recorded CSS content can be prohibited. Here, the discrimination between the recordable DVD disc and the read-only DVD disc may be performed depending on the magnitude of the push-pull signal. Since the read-only DVD disc has no guide groove on the substrate, the push-pull signal is smaller than that of the recordable DVD disc having the guide groove. For this reason, when the detected push-pull signal is smaller than a predetermined value, the reproducing apparatus determines that the read-only DVD disc is used, and when the detected push-pull signal is larger than the predetermined value, the reproducing apparatus Type DVD disc.

  By the way, recently, in a rental video store or the like, a business form has been considered in which video content distributed from the Internet is recorded on a recordable DVD disc supplied from a distributor and rented to a customer. . However, even though the recordable DVD disc recorded in this way is not illegally copied, if the customer tries to play it on a playback device at home, the recordable DVD disc is illegal because it is a recordable DVD disc. There is a problem that reproduction is prohibited as being copied (customer cannot view), and the solution is eagerly desired. This problem can be solved by the invention <5>.

In the invention <6>, the reproduction condition is controlled based on the controlled recording condition, and further, the discriminating information relating to the medium recorded as Low to High recorded as the guide groove signal is read, and Low to High recording is performed. Recording is performed after confirming that it is a write-once optical recording medium or a CSS content recording medium.
Information indicating that the recording medium is a low to high write-once recording medium is recorded in the guide groove, and the optical recording apparatus reads this information to confirm the medium type discrimination result and record the information. Similarly, information indicating that the medium is a CSS content recording medium is recorded in the guide groove, and the optical recording device reads this information to confirm the medium type discrimination result and record the information.

In the invention <7>, the optical recording apparatus further includes means for acquiring content information via a network, and is acquired by the means after determining that the optical recording apparatus is a Low to High recordable recording medium. Content information can be recorded.
<8> invention comprises the optical recording device according to any one of <2>, <4>, <5>, <6>, and a server connected to the optical recording device via a network, Content-recorded write-once light comprising means for acquiring content information and means for permitting recording of the acquired content information when it is determined that the write-once optical recording medium is subjected to Low to High recording This is a recording medium creation system that can efficiently capture content information and create a content-recordable write-once optical recording medium.

(Optical recording medium)
The optical recording medium recorded by the optical recording apparatus of the present invention preferably has a dye recording layer. Needless to say, it is only required to be able to perform Low to High recording. For example, a phase change recording layer may be provided instead of the dye recording layer. Furthermore, you may have the other layer suitably selected according to the objective.
-Dye recording layer-
The dye recording layer can be appropriately selected according to the purpose from being able to form a recording mark portion with recording light having a DVD laser wavelength (640 to 680 nm), but it is required to be recorded low to high. It is. When recording is performed in the Low to High mode, the recording sensitivity (light absorption rate) of the optical recording medium is excellent, and the recording characteristics during high-speed recording are excellent.
For the definition of push-pull signal, radial contrast signal, difference signal, reflectance, etc., measurement method, etc. in the present invention, refer to “DVD + R 4.7 GBytes Basic Format Specification version 1.3 system standard (hereinafter referred to as DVD + R system standard”). The DVD evaluation apparatus manufactured by Pulstec Co., Ltd. used in the examples described later is based on the measurement conditions of the system standard.

The dye recording layer preferably has at least one of the following characteristics 1 to 6.
-Characteristic 1-
The reflectance of the unrecorded portion of the dye recording layer is 12% to 30%. More preferably, it is 16% to 30%.
By being 12% to 30%, it is possible to easily determine the medium type based on the reflectance. If the reflectance is less than 12%, it is difficult to obtain a track servo, it does not conform to system standards such as DVD + R, DVD-R, etc., and it is difficult to set recording / reproduction with an existing drive, but when it is 12% or more, Track servo can be easily obtained, conforms to system standards such as DVD + R, DVD-R, etc., makes it easy to set recording / reproduction with an existing drive, and if it is 16% or more, it is advantageous in that the effect becomes remarkable. It is. Also, if the reflectance exceeds 30%, it is difficult to obtain the degree of modulation after recording, which is not preferable. That is, even if the reflectance after recording becomes 45%, if the unrecorded reflectance is 30%, only a modulation factor of 33% [= (45-30) / 45] can be obtained.

-Characteristic 2-
The push-pull signal [= push-pull (difference signal) / reflectance (sum signal)] of the dye recording layer is less than 0.3.
By being less than 0.3, it is possible to easily determine the medium type with the push-pull signal. When the push-pull signal is excessively large, there is a problem that a signal from the guide groove is mixed into the data signal as a noise component.
On the other hand, in an optical recording medium having a high reflectance after recording, the push-pull signal can be easily reduced. For this reason, it can prevent that the signal by a guide groove mixes in a data signal as a noise component.

-Characteristic 3-
With the optical recording medium set, the push-pull signal of the optical recording medium is measured. If the push-pull signal is in the first range, it is determined that the optical recording medium is read-only. When the recording medium is used in a reproducing apparatus that determines that the optical recording medium is writable when it is in the second range larger than the range, the push-pull signal after recording of the recording mark portion in the dye recording layer is the first Be in range.
In this case, since the optical recording medium is determined to be read-only after recording, the recorded optical recording medium is illegally copied even if a reproducing apparatus that reproduces only the optical recording medium determined to be a read-only medium is used. This is advantageous in that it can be easily reproduced without being determined as being.
The first range and the second range are appropriately set in various reproducing apparatuses, and an optical recording medium suitable for the first range and the second range can be used. For example, when the first range is “0.45 or less” and the second range is “0.46 or more”, an optical recording medium in which the push-pull signal after recording is 0.45 or less is used. Can do. Considering the first range of various playback devices, if it is less than 0.3, it is surely identified whether or not it is a read-only medium (the playback device belongs to the first range or the second range). It is advantageous in that it does not belong.

-Characteristic 4-
The push-pull signal after recording in the recording mark portion of the dye recording layer is reduced to 0.9 times or less, more preferably 0.8 times or less compared to before recording.
If it is 0.9 times or less, the effect of reducing the signal noise by the above-mentioned guide groove is large, track servo is easy, and if it is 0.8 times or less, the effect becomes remarkable.

-Characteristic 5-
The signal modulation degree after recording in the recording mark portion of the dye recording layer is 50% or more, more preferably 60% or more.
If the signal modulation degree after recording is less than 50%, it is difficult to obtain the reproduction S / N of the recording signal, it does not conform to the system standard such as DVD + R, DVD-R, and it becomes difficult to set recording / reproduction with an existing drive. However, if it is 50% or more, the reproduction S / N of the recorded signal can be easily obtained, the system standard conforms to DVD + R, DVD-R, etc., and the setting of recording / reproduction with an existing drive becomes easy. It is advantageous, and if it is 60% or more, it is advantageous in that the effect becomes remarkable.

-Characteristic 6-
The value of light absorption (Abs.) At the recording / reproducing wavelength of the dye recording layer is 0.2 to 0.8, more preferably 0.3 to 0.5.
If the value of light absorption (Abs.) Is less than 0.2, it is difficult to obtain sensitivity and modulation necessary for recording, and if it exceeds 0.8, it is difficult to obtain reflectance necessary for optical recording and reproduction. Within the range of ~ 0.8, the reflectance required for optical recording / reproduction can be easily obtained, the sensitivity and modulation required for recording can be easily obtained, and within the range of 0.3-0.5. If present, it is advantageous in that the effect is remarkable.

-Dye material-
The dye material contains at least the dye material (A) whose maximum absorption peak wavelength is longer than the recording / reproducing wavelength. More preferably, the dye material (A) and the dye material (B) having a maximum absorption peak wavelength shorter than the recording / reproducing wavelength are contained. The content ratio of the coloring material (A) and (B), (B) / [(A) + (B)], is preferably 0 to 0.9 by weight, and preferably 0.2 to 0.6. It is more preferable that
If it is in the range of 0 to 0.9, the reflectance necessary for optical recording and reproduction can be easily obtained, and the sensitivity, modulation degree, and recording power margin necessary for recording can be easily obtained, and 0.2 It is advantageous at the point that the effect is remarkable in the range of -0.6.
There is no restriction | limiting in particular as a pigment | dye material (A) and a pigment | dye material (B), According to the objective, it can select suitably.
The maximum absorption peak wavelength of the film of the dye material (A) is preferably 0 to 120 nm longer than the recording / reproducing wavelength. For example, in the case of a DVD laser wavelength (640 to 680 nm), a range of 640 to 760 nm is preferable.
On the other hand, the maximum absorption peak wavelength of the film of the dye material (B) is preferably 0 to 120 nm shorter than the recording / reproducing wavelength. For example, in the case of a DVD laser wavelength (640 to 680 nm), a range of 560 to 640 nm is preferable.

The optical recording medium subject to the present invention is characterized by the Low to High recording mode. In this case, the main recording material is the dye material (A). The dye material (A) is required to have a light absorption characteristic at the DVD laser wavelength, and a preferable range of the maximum absorption peak wavelength is 640 to 760 nm.
On the other hand, the dye material (B) is a material having smaller light absorption characteristics at the DVD laser wavelength than the dye material (A), and the preferred range of the maximum absorption peak wavelength is 560 to 640 nm.
The difference between the maximum absorption peak wavelength of the dye material (A) and the maximum absorption peak wavelength of the dye material (B) is preferably 40 nm or more, more preferably 100 nm or more. When the difference between the maximum absorption peak wavelengths is less than 40 nm, the High to Low and Low to High characteristics are offset, making it difficult to obtain the degree of modulation.
In addition, the light absorption spectrum of the film has two peaks as shown in FIG.
In general, the long wavelength side has the maximum peak value, but the short wavelength side may have the maximum peak. When the maximum absorption peak of the dye material (A) is on the short wavelength side and the maximum absorption peak wavelength of the dye material (B) is on the long wavelength side, the difference in maximum absorption peak wavelength is small, while the dye material ( When the maximum absorption peak of A) is on the long wavelength side and the maximum absorption peak wavelength of the dye material (B) is on the short wavelength side, the difference in maximum absorption peak wavelength is large.
The maximum peak wavelength can also be confirmed by a solution spectrum in which a dye is dissolved in a solvent. In particular, the difference in the maximum peak wavelength can be easily confirmed by a solution spectrum.

Examples of such a dye material include cyanine dyes, azo dyes, phthalocyanine dyes, squarylium dyes, and the like. These may be used individually by 1 type and may use 2 or more types together. When these dye materials have a substituent, the adjustment of the light absorption wavelength becomes easy, and it becomes easy to obtain thermal decomposition characteristics (for example, 150 to 250 ° C.) suitable for optical recording. Is preferable.
The cyanine dye is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include Japanese Patent No. 3834053, Japanese Patent No. 2594443, Japanese Patent No. 3698708, Japanese Patent No. 3659922, and Japanese Patent Laid-Open No. 3659922. Illustrative compounds described in JP 2005-205874 A and the like can be mentioned.
There is no restriction | limiting in particular as said azo dye, Although it can select suitably according to the objective, For example, the exemplary compound as described in patent 384053 gazette, patent 3787722 gazette, patent 2870952 grade | etc., Is mentioned. .
The phthalocyanine dye is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include those described in Japanese Patent Publication No. 7-56019, Japanese Patent Publication No. 7-116371, Japanese Patent No. 3836192, and the like. Compounds.
There is no restriction | limiting in particular as said squarylium pigment | dye, Although it can select suitably according to the objective, For example, the exemplary compound as described in Unexamined-Japanese-Patent No. 2002-552074, Unexamined-Japanese-Patent No. 2001-544855 etc. is mentioned.

Among the dye materials, in the present invention, a cyanine dye represented by the following general formula (I) is preferable from the viewpoint of easy adjustment of the light absorption wavelength and excellent recording characteristics. Furthermore, the structure of the following general formula (I) may be a dimer structure via a linking group. These details are described in International Publication No. 06/123807 pamphlet.
<General formula (I)>
In the above formula, R ′ and R ″ each independently represents an alkyl group, an aralkyl group or an aryl group, which may be substituted with a substituent, and adjacent R ″ are bonded to each other to form an alicyclic ring. Formula hydrocarbon rings or heterocycles may be formed. At least one of R ″ is preferably a benzyl group which may have a substituent. In this case, it is advantageous in that the thermal decomposition temperature of the dye material is suitable for forming a recording mark portion, and This is advantageous in that the decomposition temperature of the dye material is lowered, the decomposition rate is high, and the calorific value tends to be small.
Z represents an atomic group for forming an aromatic ring.
X represents a monovalent anion, PF ₆ ^- is preferably. X is PF ₆ ^- when a is advantageous in that the thermal decomposition temperature of the dye material is suitable for forming the recording mark portion, also, the decomposition temperature is low temperature of the dye material, fast degradation rate, calorific value This is advantageous in that it tends to be small.
L represents a linking group for forming carbocyanine. As the dye material (A) suitable for the DVD laser wavelength (640 to 680 nm), L is preferably a pentamethine group having 5 carbon atoms, and the dye material (B) is a trimethine group having 3 carbon atoms. Is preferred. This is advantageous in that the film optical characteristics suitable for the recording light wavelength can be obtained by the number of carbons of L.

The dye material (B) suitable for the DVD laser wavelength (640 to 680 nm) is preferably a squarylium dye represented by the following general formula (II).
<General formula (II)>
In the above formula, R ¹ and R ² may be the same or different, and have a hydrogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, or a substituent. An aryl group which may be substituted or a heterocyclic group which may have a substituent, Q represents a metal atom having coordination ability, q represents 2 or 3, R ³ and R ⁴ May be the same or different and each represents a hydrogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, or an aryl group that may have a substituent. , R ³ and R ⁴ may be bonded to each other to form an alicyclic hydrocarbon ring or a heterocyclic ring, and R ⁵ is a hydrogen atom, an alkyl group which may have a substituent, or a substituent. the represents an aryl group which may be have aralkyl groups or substituents have, R A halogen atom, an optionally substituted alkyl group, an optionally substituted aralkyl group, an optionally substituted aryl group, a nitro group, a cyano group or a substituent Represents an alkoxy group which may have, p represents an integer of 0 to 4, and when p is 2 to 4, R ⁶ may be the same or different, and two R ⁶ adjacent to each other. May combine with two adjacent carbon atoms to form an optionally substituted aromatic ring.
Furthermore, R ¹ is preferably a phenyl group. R ² is preferably a halogen-substituted or unsubstituted alkyl group or an alkyl group having a branched chain, and more preferably a trifluoromethyl group or an isopropyl group. R ³ and R ⁴ are preferably unsubstituted aryl groups, and more preferably benzyl groups. R ⁶ is preferably a naphthyl group formed with a benzene ring.

In the definition of the substituent of the general formula (II), the alkyl part of the alkyl group and the alkoxy group includes a linear or branched alkyl group having 1 to 6 carbon atoms or a cyclic alkyl group having 3 to 8 carbon atoms. For example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, 1-methylbutyl group, 2-methylbutyl group, tert -Pentyl group, hexyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like.
As the aralkyl group, those having 7 to 19 carbon atoms are preferable, those having 7 to 15 carbon atoms are more preferable, and examples thereof include a benzyl group, a phenethyl group, a phenylpropyl group, and a naphthylmethyl group.
The aryl group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, an anthryl group, and an azulenyl group.
Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.
In addition, examples of the metal atom Q having coordination ability include aluminum, zinc, copper, iron, nickel, chromium, cobalt, manganese, iridium, vanadium, titanium, and the like. In particular, a complex in which Q is aluminum is formed. The optical recording medium of the present invention using the prepared squarylium dye has excellent optical characteristics.

The aromatic ring formed by combining two R ⁶ adjacent to each other with two adjacent carbon atoms is preferably one having 6 to 14 carbon atoms, and examples thereof include a benzene ring and a naphthalene ring. .
The heterocyclic ring in the heterocyclic group is a 5-membered or 6-membered monocyclic aromatic or alicyclic heterocyclic ring containing at least one atom selected from a nitrogen atom, an oxygen atom and a sulfur atom, Examples include condensed bicyclic or tricyclic condensed rings containing at least one atom selected from a nitrogen atom, an oxygen atom, and a sulfur atom, and alicyclic heterocycles. Pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, quinoline ring, isoquinoline ring, phthalazine ring, quinazoline ring, quinoxaline ring, naphthyridine ring, cinnoline ring, pyrrole ring, pyrazole ring, imidazole ring, triazole ring, tetrazole ring, thiophene ring , Furan ring, thiazole ring, oxazole ring, indole ring, isoindole ring, indazole ring, benzimidazole ring, Zotriazole ring, benzothiazole ring, benzoxazole ring, purine ring, carbazole ring, pyrrolidine ring, piperidine ring, piperazine ring, morpholine ring, thiomorpholine ring, homopiperidine ring, homopiperazine ring, tetrahydropyridine ring, tetrahydroquinoline ring, Examples include a tetrahydroisoquinoline ring, a tetrahydrofuran ring, a tetrahydropyran ring, a dihydrobenzofuran ring, and a tetrahydrocarbazole ring.

The aralkyl group, aryl group, alkoxy group, heterocyclic group, and aromatic ring substituents formed by combining two adjacent R ⁶ atoms with two adjacent carbon atoms may be the same or different. Examples thereof include 1 to 5 substituents such as a hydroxyl group, a carboxyl group, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a nitro group, and a substituted or unsubstituted amino group. Examples of the halogen atom, alkyl group, and alkoxy group include the same ones as described above.
Examples of the substituent of the alkyl group include 1 to 3 substituents which may be the same or different, for example, a hydroxyl group, a carboxyl group, a halogen atom, and an alkoxy group. Examples of the halogen atom and alkoxy group include the same as described above.
Examples of the substituent of the amino group include one or two alkyl groups which may be the same or different, and examples of the alkyl group in this case include the same ones as described above.
The squarylium dye represented by the structural formula (II) can be produced according to the method described in WO 02/50190.

Specific examples of the squarylium dye are shown in Table 1. In the table, Ph is a phenyl group, CF ₃ is a trifluoromethyl group, CH ₃ is a methyl group, t-Bu is a tertiary butyl group, i-Pr is an isopropyl group, and cyclohexyl is R ³ and R ⁴ are mutually bonded. A 6-membered ring formed by bonding is represented.
Further, the position of the substituent of R ⁶ is No. described later for naphthyl. 8 is the same as in the case of No. 8, and CH ₃ is No. described later. The same as in the case of 8.

No. in Table 1 1, no. 8, no. The structural formula of 11 squarylium dyes is shown below.
<No. 1>
<No. 8>
<No. 11>

Next, in the present invention, in addition to the dye material, other components may be contained in the dye recording layer as necessary for the purpose of improving light resistance, improving optical characteristics, improving temperature and humidity resistance, and the like.
As such a material, as a light resistance improver, a light resistant material (C) having a maximum absorption peak wavelength on the longer wavelength side than the recording / reproducing wavelength or a light resistant material having a maximum absorption peak wavelength on the shorter wavelength side than the recording / reproducing wavelength. It is preferable to contain material (D). Furthermore, it is preferable to contain together one each of light-resistant material (C) and light-resistant material (D).
This is because the light-resistant material (C) effectively acts on the dye material (A) and the light-resistant material (D) acts on the dye material (B) because the light absorption wavelength is close.
Examples of light-resistant materials include pyrylium / thiopyrylium dyes, azurenium dyes, formazan chelate complexes, azo metal complexes, dithiol metal complexes, metal complex salt dyes such as Ni and Cr, naphthoquinone / anthraquinone dyes, indophenol dyes, indoaniline dyes, Examples include phenylmethane dyes, triallylmethane dyes, aminium / diimonium dyes, and nitroso compounds. If these dye materials have a substituent, the adjustment of the light absorption wavelength is facilitated, and the thermal decomposition characteristics suitable for optical recording (the light-resistant material is not directly related to recording. The temperature may be higher than that of the dye of the dye recording layer. For example, it is preferable to obtain 150 to 300 ° C.).
In particular, examples of the light fastness improver of the dye material (A) suitable for the DVD laser wavelength (640 to 680 nm) include a dithiol metal complex, an aminium / diimonium dye, and a dye material suitable for the DVD laser wavelength (640 to 680 nm) (B ) Is preferably a formazan chelate complex or an azo metal complex.

There is no restriction | limiting in particular in the said dithiol metal complex, Although it can select suitably according to the objective, For example, the exemplary compound as described in patent 30020256, the Chemical Society of Japan, 1992, (10), p1141-1143, etc. Is mentioned.
The aminium / diimonium dye is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include Japanese Patent Publication No. 6-26028, Japanese Patent No. 3097628, Japanese Patent No. 3721283, and Japanese Patent No. 3871282. Illustrative compounds described in publications and the like can be mentioned.
There is no restriction | limiting in particular in the said formazan chelate complex, Although it can select suitably according to the objective, For example, patent 3456621, Unexamined-Japanese-Patent No. 2001-23235, Unexamined-Japanese-Patent No. 2002-293027, international publication 00 / 075111 pamphlet, Japanese Patent No. 2791944, and the like.
There is no restriction | limiting in particular in the said azo metal complex, Although it can select suitably according to the objective, For example, the exemplary compound as described in Unexamined-Japanese-Patent No. 2002-201373, Unexamined-Japanese-Patent No. 2005-205874, etc. is mentioned.

The formazan chelate complex is particularly preferable because it contains a formazan compound represented by the following general formula (III) or (IV) and a compound in which a metal forms a complex because the storage stability is improved.
<General formula (III)>
[In the formula, ring T represents a substituted or unsubstituted 5-membered ring or 6-membered ring containing a nitrogen atom, Z represents an atomic group giving ring T, and the heterocycle containing the nitrogen atom includes other rings. A ⁰ represents an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkylcarbonyl group which may have a substituent, and a substituent. An arylcarbonyl group which may have, an alkenyl group which may have a substituent, a heterocyclic residue which may have a substituent or an alkyloxycarbonyl group which may have a substituent; shows, B ⁰ represents an optionally substituted alkyl group, which may have a substituent alkenyl group, an optionally substituted aryl group. ]

<General formula (IV)>
[Wherein, ring U and ring V may be the same or different and each represents a substituted or unsubstituted 5-membered or 6-membered ring containing a nitrogen atom, and Z ¹ and Z ² represent ring U and ring, respectively. A group of atoms giving V, and the heterocycle containing the nitrogen atom may be condensed with another ring, and A ¹ and A ² each represents an alkyl group or a substituent which may have a substituent. An aryl group which may have, an alkylcarbonyl group which may have a substituent, an arylcarbonyl group which may have a substituent, an alkenyl group which may have a substituent, and a substituent; A heterocyclic residue which may have or an alkyloxycarbonyl group which may have a substituent, B ¹ and B ² have an alkylene group which may have a substituent and a substituent. May have an alkenylene group or a substituent Shows the arylene group, W is -CH ₂ -, or SO ₂ - indicates, n is 0 or 1. ]

Another ring D may be bonded to each of the ring T, the ring U, and the ring V. In this case, the ring D includes a carbocyclic ring and a heterocyclic ring. In the case of a carbocyclic ring, the number of carbon atoms constituting the ring is preferably 6-20, more preferably 6-10. Specific examples include a benzene ring, a naphthalene ring, and a cyclohexane ring. Moreover, in the case of a heterocyclic ring, the number of ring-constituting atoms is preferably 5 to 20, more preferably 5 to 14. Specific examples include pyrrolidine ring, thiazole ring, imidazole ring, thiadiazole ring, oxazole ring, triazole ring, pyrazole ring, oxadiazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, quinoline ring, indoline. Ring, carbazole ring and the like.
Specific examples of the substituent bonded to ring T, ring U, and ring V may each independently have a halogen atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, an amino group, a carbamoyl group, or a substituent. A good alkyl group, an aryl group which may have a substituent, a heterocyclic group which may have a substituent, an alkoxy group which may have a substituent, and a substituent which may have a substituent An aryloxy group, an optionally substituted alkylthio group, an optionally substituted arylthio group, an optionally substituted alkylamino group, and optionally having a substituent An arylamino group, an alkoxycarbonyl group which may have a substituent, an aryloxycarbonyl group which may have a substituent, an alkylcarboxamide group which may have a substituent, and a substituent The A good arylcarboxamide group, an optionally substituted alkylcarbamoyl group, an optionally substituted arylcarbamoyl group, an optionally substituted alkenyl group, and a substituent. And an alkylsulfamoyl group that may be used.

In the general formulas (III) and (IV), A ⁰ , A ¹ , and A ² each represents an alkyl group that may have a substituent, an aryl group that may have a substituent, and a substituent. An alkylcarbonyl group which may have, an arylcarbonyl group which may have a substituent, an alkenyl group which may have a substituent, a heterocyclic group which may have a substituent, or a substituent The alkoxycarbonyl group which may have a group is shown. In this case, the alkyl group and alkenyl group include chain and cyclic groups. Carbon number of an alkyl group becomes like this. Preferably it is 1-15, More preferably, it is 1-8. Carbon number of an alkenyl group becomes like this. Preferably it is 2-8, More preferably, it is 2-6.
In the general formula (III), B ⁰ represents an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an aryl group which may have a substituent. . The alkyl group and alkenyl group in this case include chain and cyclic groups. Carbon number of an alkyl group becomes like this. Preferably it is 1-15, More preferably, it is 1-8, Carbon number of an alkenyl group becomes like this. Preferably it is 2-8, More preferably, it is 2-6. Carbon number of an aryl group becomes like this. Preferably it is 6-18, More preferably, it is 6-14.
In the general formula (IV), B ¹ and B ² may each have an alkylene group which may have a substituent, an alkenylene group which may have a substituent, or a substituent. An arylene group is shown. In this case, the alkylene group and alkenylene group include chain and cyclic groups. Carbon number of an alkylene group becomes like this. Preferably it is 1-15, More preferably, it is 1-8. The alkenylene group preferably has 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms. The carbon number of the arylene group is preferably 6-18, more preferably 6-14.

  Examples of each alkyl group in the general formulas (III) and (IV) include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, Linear alkyl group such as n-octyl group, n-nonyl group, n-decyl group, isobutyl group, isoamyl group, 2-methylbutyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group 2-ethylbutyl group, 2-methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 2-ethylpentyl group, 3-ethylpentyl group, 2-methylheptyl group, 3- Methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 2-ethylhexyl group, 3-ethylhexyl group, isopropyl group, sec-butyl group, 1-ethyl Propyl group, 1-methylbutyl group, 1,2-dimethylpropyl group, 1-methylheptyl group, 1-ethylbutyl group, 1,3-dimethylbutyl group, 1,2-dimethylbutyl group, 1-ethyl-2-methyl Propyl group, 1-methylhexyl group, 1-ethylheptyl group, 1-propylbutyl group, 1-isopropyl-2-methylpropyl group, 1-ethyl-2-methylbutyl group, 1-propyl-2-methylpropyl group, 1-methylheptyl group, 1-ethylhexyl group, 1-propylpentyl group, 1-isopropylpentyl group, 1-isopropyl-2-methylbutyl group, 1-isopropyl-3-methylbutyl group, 1-methyloctyl group, 1-ethyl Heptyl, 1-propylhexyl, 1-isobutyl-3-methylbutyl, neopentyl, tert-butyl Branched alkyl group such as til group, tert-hexyl group, tert-amyl group, tert-octyl group, cyclohexyl group, 4-methylcyclohexyl group, 4-ethylcyclohexyl group, 4-tert-butylcyclohexyl group, 4- ( 2-Ethylhexyl) cyclohexyl group, bornyl group, isobornyl group, cycloalkyl group such as adamantyl group, and the like can be mentioned. Among them, those having 1 to 8 carbon atoms are preferable.

Each alkyl group may be substituted with a hydroxyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, or the like, and may have a specific substituent (for example, a halogen atom or a nitro group). It may be substituted with an aryl group or a heterocyclic group.
Furthermore, it may be substituted with another hydrocarbon group such as the alkyl group through a heteroatom such as oxygen, sulfur or nitrogen.
Examples of alkyl groups substituted with other hydrocarbon groups through oxygen include methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, butoxyethyl group, ethoxyethoxyethyl group, phenoxyethyl group, methoxypropyl And an alkyl group substituted with an alkoxy group such as an ethoxypropyl group, an aryloxy group, or the like. These alkoxy groups and aryloxy groups may further have a substituent.
Examples of the alkyl group substituted with other hydrocarbon groups via sulfur include alkylthio groups such as methylthioethyl group, ethylthioethyl group, ethylthiopropyl group, and phenylthioethyl group, and arylthio groups. Is mentioned. These alkylthio groups and arylthio groups may further have a substituent.
Alkyl groups substituted with other hydrocarbon groups via nitrogen were substituted with alkylamino groups such as dimethylaminoethyl group, diethylaminoethyl group, diethylaminopropyl group, phenylaminomethyl group, arylamino groups, etc. An alkyl group is mentioned. These alkylamino groups and arylamino groups may further have a substituent.

As the alkenyl group in the general formulas (III) and (IV), those having 2 to 6 carbon atoms are preferable, for example, vinyl group, allyl group, 1-propenyl group, methacryl group, crotyl group, 1-butenyl group, 3 -Butenyl group, 2-pentenyl group, 4-pentenyl group, 2-hexenyl group, 5-hexenyl group, 2-heptenyl group, 2-octenyl group and the like can be mentioned. Examples of the substituent for the alkenyl group include the same as those for the alkyl group.
Specific examples of the aryl group in the general formulas (III) and (IV) include a phenyl group, a naphthyl group, an anthranyl group, a fluorenyl group, a phenalenyl group, a phenanthrenyl group, a triphenylenyl group, and a pyrenyl group.
Examples of the alkylene group and alkenylene group in the general formulas (III) and (IV) include those obtained by removing one hydrogen atom from the alkyl group and alkenyl group.
Examples of the arylene group in the general formulas (III) and (IV) include those obtained by removing one hydrogen atom from the aryl group.
The aryl group and arylene group in the general formulas (III) and (IV) are an alkyl group, an alkenyl group, a hydroxyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, a trifluoromethyl group, a specific substituent (for example, An aryl group which may have a halogen atom or a nitro group, or a heterocyclic group which may have a specific substituent (for example, a halogen atom or a nitro group). Here, examples of the alkyl group, alkenyl group, and aryl group include those described above, and examples of the halogen atom include fluorine, chlorine, bromine, and iodine atoms.

Specific examples of the heterocyclic group in the general formulas (III) and (IV) include a furyl group, a thienyl group, a pyrrolyl group, a benzofuranyl group, an isobenzofuranyl group, a benzothienyl group, an indolinyl group, an isoindolinyl group, and a carbazolyl group. , Pyridyl group, piperidyl group, quinolyl group, isoquinolyl group, oxazolyl group, isoxazolyl group, thiazolyl group, isothiazolyl group, imidazolyl group, pyrazolyl group, benzoimidazolyl group, pyrazyl group, pyrimidinyl group, pyridazinyl group, quinoxalinyl group and the like.
These heterocyclic groups are a hydroxyl group, an alkyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, an aryl group which may have a specific substituent (for example, a halogen atom or a nitro group), a specific substitution May be substituted with a heterocyclic group or the like which may have a group (for example, a halogen atom or a nitro group), and may be substituted with a heteroatom such as oxygen, sulfur, nitrogen, etc. It may be substituted with a hydrocarbon group. Here, examples of the alkyl group, alkenyl group, aryl group, and halogen atom are the same as those described above.

The alkoxy group which may have a substituent may be any group in which an alkyl group which may have a substituent is directly bonded to an oxygen atom. Specific examples of the alkyl group and the substituent include the above-described examples.
The aryloxy group which may have a substituent may be any group in which an aryl group which may have a substituent is directly bonded to an oxygen atom. Specific examples of the aryl group and substituent include the above-described examples.
The alkylthio group that may have a substituent may be any group in which an alkyl group that may have a substituent is directly bonded to a sulfur atom. Specific examples of the alkyl group and the substituent include the above-described examples.
The arylthio group which may have a substituent may be any group in which an aryl group which may have a substituent is directly bonded to a sulfur atom. Specific examples of the aryl group and substituent include the above-described examples.
The alkylamino group which may have a substituent may be any group in which an alkyl group which may have a substituent is directly bonded to a nitrogen atom. Specific examples of the alkyl group and the substituent include the above-described examples. In addition, alkyl groups may be bonded to each other to form a ring such as a piperidino group, a morpholino group, a pyrrolidinyl group, a piperazinyl group, an indolinyl group, or an isoindolinyl group containing an oxygen atom or a nitrogen atom.
The arylamino group that may have a substituent may be any group in which an aryl group that may have a substituent is directly bonded to a nitrogen atom. Specific examples of the aryl group and substituent include the above-described examples.

The alkylcarbonyl group which may have a substituent may be any group in which an alkyl group which may have a substituent is directly bonded to a carbon atom of the carbonyl group. The above-mentioned example can be given as a specific example.
The arylcarbonyl group which may have a substituent may be any group in which the aryl group which may have a substituent is directly bonded to the carbon atom of the carbonyl group. Specific examples of the aryl group and substituent include the above-described examples.
The alkoxycarbonyl group that may have a substituent may be any group in which an alkyl group that may have a substituent is directly bonded to an oxygen atom. Specific examples of the alkyl group and the substituent include the above-described examples.
The aryloxycarbonyl group which may have a substituent may be any group in which an aryl group which may have a substituent is directly bonded to an oxygen atom. Specific examples of the aryl group and substituent include the above-described examples.
The alkylcarboxamide group that may have a substituent may be any group in which an alkyl group that may have a substituent is directly bonded to a carbon atom of the carboxamide. Specific examples of the alkyl group and the substituent include the above-described examples.
The arylcarboxamide group which may have a substituent may be any group in which the aryl group which may have a substituent is directly bonded to the carbon atom of the carboxamide. Specific examples of the aryl group and substituent include the above-described examples.

The alkylcarbamoyl group which may have the substituent may be any group in which the alkyl group which may have a substituent is directly bonded to the nitrogen atom of the carbamoyl group. Specific examples of the alkyl group and the substituent include the above-described examples. In addition, alkyl groups may be bonded to each other to form a ring such as a piperidino group, a morpholino group, a pyrrolidinyl group, a piperazinyl group, an indolinyl group, or an isoindolinyl group containing an oxygen atom or a nitrogen atom.
The arylcarbamoyl group which may have a substituent may be any group as long as the aryl group which may have a substituent is directly bonded to the nitrogen atom of the carbamoyl group. Specific examples of the aryl group and substituent include the above-described examples.
The alkylsulfamoyl group that may have a substituent may be any group in which an alkyl group that may have a substituent is directly bonded to the nitrogen atom of the sulfamoyl group. Specific examples of the alkyl group and the substituent include the above-described examples.

  The metal component in the formazan metal chelate complex may be any metal or metal compound that can form a chelate with formazan, such as titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, Zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium and their oxides and halides are included. As the metal component, vanadium, manganese, iron, cobalt, nickel, copper, zinc, and palladium are particularly preferable. The optical recording medium of the present invention using the formazan metal chelate compound of these metals has excellent optical characteristics. Yes. Of the halides, chloride is preferably used.

As the dithiol metal complex, it is particularly preferable that a dithiol compound represented by the following general formula (V) and a metal M contain a complex to improve storage stability.
<General formula (V)>
In the above formula, R 1, R 2, R 3 and R 4 may be the same or different and have an alkyl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent. Represents an aryl group that may be substituted, a heterocyclic group that may have a substituent, a halogen, a nitro group, a cyano group, or a hydrogen atom, and p, q, r, and s are each independently 0 to 4 Represents an integer. M represents Ni or Cu.

Next, a layer structure that can be employed in the optical recording medium of the present invention will be described with reference to the drawings.
FIG. 2 shows the layer structure of an optical recording medium of DVD + R and DVD-R, and FIG. 3 shows the layer structure of an optical recording medium having a reverse layer configuration adopted in BD-R.
The optical recording medium of FIG. 2 has a substrate 1, a dye recording layer (optical recording layer) 2, a reflective layer 3, and a dummy substrate 4 in this order from the side on which recording / reproducing light enters.
3 has a light-transmitting cover layer 6, a light-transmitting protective layer 5, a dye recording layer (optical recording layer) 2, a reflecting layer 3, and a substrate 1 from the side on which recording / reproducing light enters. In this order.
In addition, you may provide the various layers for the purpose of optical enhancement, protection durability, smoothness, and adhesive provision between each said layer.

-Substrate 1 and dummy substrate 4-
There is no restriction | limiting in particular in the material of the board | substrate 1 and the dummy board | substrate 4, According to the objective, it can select suitably, For example, vinyl chloride, such as acrylic resins, such as a polymethylmethacrylate, a polyvinyl chloride, a vinyl chloride copolymer Glass, ceramics, etc., such as resin, epoxy resin, polycarbonate resin, amorphous polyolefin, polyester, soda-lime glass. Among these, polymethyl methacrylate, polycarbonate resin, epoxy resin, amorphous polyolefin, polyester, glass, and the like are preferable from the viewpoint of dimensional stability, transparency, flatness, etc., and polycarbonate resin is easy to mold. Is particularly preferred.
The substrate 1 is formed with at least one of guide grooves and pits.
The groove depth and groove width (half width) of the guide groove formed on the surface of the substrate 1 can be appropriately selected according to the recording / reproducing wavelength or the like.
The groove depth is preferably 200 to 1000 mm (20 to 100 nm). In this range, it is easy to reduce the push-pull signal after recording more than the unrecorded push-pull signal, and it is advantageous in that it is easy to obtain an unrecorded push-pull signal necessary for track servo. It is.
When a DVD laser wavelength (640 to 680 nm) is used, the groove depth is preferably 200 to 700 mm (20 to 70 nm), and the groove width (half width) is 20 to 60% of the track pitch. Preferably there is. In these ranges, a design suitable for recording at the DVD laser wavelength is possible and can be adjusted as desired according to the signal characteristics.

Further, address information and medium information are recorded in advance in the guide groove. These pieces of information are recorded by phase modulation wobble in DVD + R and by Lpp wobble in DVD-R.
This method is described in the DVD + R system standard described above for DVD + R, and in the DVD specifications for Recordable Disc (DVD-R) standard for DVD-R.
In the present invention, Low to High medium type discrimination information can be easily added by these codings.

-Pregroove layer-
A pre-groove layer may be provided on the substrate 1 (or an undercoat layer described later) for the purpose of forming irregularities representing information such as the guide grooves or address signals.
There is no restriction | limiting in particular in the material of this pregroove layer, According to the objective, it can select suitably, For example, at least 1 type of monomer (or oligomer) of the monoester, diester, triester, and tetraester of acrylic acid And a mixture of a photopolymerization initiator and the like.

-Undercoat layer-
On the surface of the substrate 1 on the side where the dye recording layer 2 is provided and / or on the reflective layer 3, for the purposes of improving flatness, improving adhesion, preventing deterioration of the dye recording layer 2, and further enhancing the signal, A pulling layer may be provided.
The material for the undercoat layer is not particularly limited and may be appropriately selected depending on the purpose. For example, polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl sulfonic acid copolymer, styrene / vinyl toluene copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer , Ethylene / vinyl acetate copolymer, polymer materials such as polyethylene, polypropylene, polycarbonate, UV curable resin, organic substances such as adhesives and silane coupling agents, inorganic oxides (SiO ₂ , Al ₂ O ₃ , SnO _{2 , Ta 2 O 5, Nb 2} O 5 ), Inorganic sulfides (ZnS, etc. SnS), inorganic materials such as inorganic fluorides (such as MgF _2), or the like mixtures thereof.
There is no restriction | limiting in particular in the thickness of an undercoat layer, Although it can select suitably according to the objective, Generally, it is about 100 to 20 micrometers.

-Reflective layer 3-
On the dye recording layer (optical recording layer) 2, a reflective layer 3 is provided for the purpose of improving the S / N ratio, the reflectance, and the sensitivity during recording.
As a material of the reflective layer 3, a light reflective substance is used.
The light-reflective material is a material having high reflectivity with respect to laser light. Examples thereof include Mg, Se, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, and Re. Fe, Co, Ni, Ru, Rh, Pd, Ir, Pt, Cu, Ag, Au, Zn, Cd, Al, Ca, In, Si, Ge, Te, Pb, Po, Sn, Si, Nd, etc. A metal, a semimetal, etc. are mentioned. Among these, Au, Al, and Ag are preferable. These light reflecting materials may be used alone or in combination of two or more.
When Al and Ag-based materials are used as the light-reflecting substances, Ti, Nb, Ta, Mn, Pd, Pt, Zn, Cd, Ca, In, Si, Ge, Sn are used for the purpose of imparting corrosion resistance. Si, Nd, etc. may be added in an amount of about 0.1 to 10% by weight.
The thickness of the reflective layer is generally about 100 to 3000 mm.

-Protective layer-
A protective layer (overcoat) may be provided on the dye recording layer 2 and the reflective layer 3 for the purpose of physically and chemically protecting them, and the dye recording layer 2 of the substrate 1 is provided. A protective layer (back coat) may be provided on the non-exposed side for the purpose of improving scratch resistance and moisture resistance.
As the material of the protective layer, for _{example, SiO, SiO 2, MgF 2} , SnO 2, ZnS, inorganic materials mainly composed of ZnO or the like, thermoplastic resins, thermosetting resins, such as ultraviolet curable resins .
The thickness of the protective layer is generally about 100 mm (10 nm) to 50 μm.
When the protective layer is a resin protective layer, it may be provided as a light-transmitting cover layer 6 as shown in FIG.

-Manufacture of optical recording media-
There is no restriction | limiting in particular in the manufacturing method of an optical recording medium, It can select suitably from well-known methods. The optical recording medium shown in FIG. 2 can be manufactured by a manufacturing method including a dye recording layer forming step, a reflective layer forming step, and a dummy substrate forming step, for example.
-Dye recording layer forming step-
The dye recording layer forming step is a step of forming the dye recording layer 2 directly or via another layer on the substrate 1 on the surface of which the guide grooves and / or pits are formed by a coating film forming means or the like.
When applying a coloring material, the coloring material is dissolved in a solvent to prepare a coating solution. As the solvent, a known organic solvent (for example, alcohol, cellosolve, halogenated carbon, ketone, ether, etc.) is used. Among these, a fluorine-substituted alcohol is preferable because it is excellent in solubility, film thickness controllability, and the like of the coloring material.
As the coating film forming means, the spin coating method is preferable because the thickness can be controlled by adjusting the concentration, viscosity, and solvent drying temperature of the dye recording layer.

-Reflection layer formation process-
The reflective layer forming step is a step of forming the reflective layer 3 on the dye recording layer 2 directly or via another layer by a vacuum film forming means or the like. For example, the reflective layer 3 made of the light reflective material is formed on the dye recording layer 2 by vacuum film forming means such as vapor deposition, sputtering, or ion plating.
-Dummy substrate formation process-
The dummy substrate forming step is a step of forming the dummy substrate 4 on the reflective layer 3.
The dummy substrate 4 may be formed on the reflective layer 3 with, for example, an adhesive, but a protective layer material made of an ultraviolet curable resin is applied between the surface of the reflective layer 3 and the dummy substrate 4 to form a dummy. It may be cured and bonded by irradiating ultraviolet rays from the substrate 4 side.

(Optical recording method)
The optical recording method of the present invention includes recording the signal mark portion by irradiating the optical recording medium of the present invention with pulsed light, and further performing other processing appropriately selected as necessary.
In this optical recording method, the optical recording medium of the present invention is irradiated with pulsed light used in general optical recording systems such as CD-R, DVD + R, DVD-R, HD DVD-R, and BD-R. As a result, recording is performed in a so-called Low to High mode. Therefore, it is possible to perform recording with excellent recording sensitivity (light absorption rate) and excellent recording characteristics during high-speed recording.
The pulsed light is not particularly limited, and can be selected from known pulsed light according to the purpose, and may include multi-pulsed light, which is a pulsed light whose intensity at the head of the pulse is changed, Or you may include the pulsed light which changed the intensity | strength of the head part and the rear-end part. When recording is performed using such pulsed light, a good signal can be recorded, and a recording pulse strategy described in the DVD + R system standard or the like can be employed.

(Optical recording device)
The optical recording apparatus is not particularly limited and can be appropriately selected according to the purpose. In general, a laser light source such as a semiconductor laser, and the laser light emitted from the laser light source are applied to an optical recording medium mounted on a spindle. Condensing lens for condensing, laser light detector for detecting part of laser light emitted from laser light source, and optical element for guiding laser light emitted from laser light source to condensing lens and laser light detector In addition, other means are provided as necessary.
An example of the configuration of the optical recording apparatus is shown in FIG. I do. At this time, the optical recording apparatus guides a part of the laser light emitted from the laser light source to the laser light detector, and controls the light amount of the laser light source based on the detection amount of the laser light of the laser light detector. The laser light detector converts a detected amount of the detected laser light into a voltage or a current and outputs it as a detected amount signal. The optical pickup 13 (recording means) in FIG. 6 includes these laser light source, optical element, condenser lens, laser light detector, and the like.

The optical recording apparatus of this embodiment is connected to a server on which content information is recorded via a network.
Functionally, the optical recording apparatus is functionally configured to detect a push-pull signal from the track error signal, a frequency detection means to detect the meandering frequency of the guide groove from the track error signal, and a medium reflection from the focus error signal. A reflectance detecting means for detecting the rate, and a reflecting surface number detecting means for detecting the number of reflecting surfaces from the focus error signal. Each of these detection means is mainly constituted by a read amplifier 15, servo means 16, and laser controller 18.
In addition, the optical recording apparatus includes a determination unit that performs various arithmetic processes based on the detection results of the detection units and determines that the recording medium is a Low to High write-once optical recording medium. The discriminating means further discriminates that it is a CSS content recording medium when it is discriminated as a low to high write-once optical recording medium. This discriminating means is constituted by the CPU 28 and the like.
In addition, the optical recording apparatus includes a control unit that controls the servo unit and the laser controller based on the determination result of the determination unit. Furthermore, a permission unit is provided for permitting recording of CSS content information when the determination unit determines that the medium is a CSS content recording medium. This control means and permission means are also constituted by the CPU 28 and the like.
Further, the optical recording apparatus includes means (for example, an interface) for acquiring content information via a network.

In the optical recording apparatus configured as described above, when a low to high write-once type optical recording medium before recording is loaded, the discriminating unit performs low to high write-once type based on the detection result of each detection unit. It is determined that the medium is an optical recording medium and a CSS content recording medium (details will be described later). Subsequently, the control unit controls the servo unit and the laser controller based on the determination result that the recording unit is a low to high write-once type optical recording medium. Thus, recording and reproduction can be performed under conditions optimized for a Low to High write-once optical recording medium. Further, the control means permits recording of CSS content information acquired via the network based on the determination result that the medium is a CSS content recording medium.
As described above, the optical recording apparatus can record and reproduce CSS content information under conditions optimized for a Low to High write-once optical recording medium.
Further, the write-once type optical recording medium which controls the recording conditions, controls the reproduction conditions, reads the discriminating information about the medium to be recorded as a guide groove signal in the guide groove, and performs the Low to High recording. It is preferable to record after confirming that it is a CSS content recording medium.
In this case, the medium type is discriminated and the recording condition is optimized. However, the recording condition may be controlled based on the detection result such as the push-pull signal.

Here, a process for determining that the recording medium is a low to high write-once type optical recording medium will be described in detail. For example, when the detection result by the push-pull signal detection means is less than 0.3 and the detection result by the frequency detection means is 818 kHz or 140 kHz (the detection result of the meander frequency is “present”), It is discriminated that it is a Low to High write-once type optical recording medium. More specifically, when the detection result by the push-pull signal detection means is 0.2, there is a possibility of either a Low to High write-once optical recording medium or a DVD-ROM. Further, when the detection result by the frequency detecting means is 818 kHz, it is determined as Low to High DVD + R, and when it is 140 kHz, it is determined as Low to High DVD-R.
As another example, the discrimination means has a detection result of less than 0.3 by the push-pull signal detection means, a detection result of the detection result of the reflectance detection means of 12 to 30%, and the detection by the reflection surface number detection means. When the result is one side, it is determined that the recording medium is a low to high write-once type optical recording medium. More specifically, when the detection result by the reflectance detection unit is 25% and the detection result by the reflection surface number detection unit is one surface, either the low to high write-once optical recording medium or the DVD + RW single layer is used. There will be a possibility. Further, when the detection result by the push-pull signal detection means is 0.2, it is determined as a Low to High write-once type optical recording medium.

Further, in the present invention, it is preferable to determine in advance that the recording medium is a Low to High recording medium. When discriminating by the radial contrast, it can be easily discriminated by detecting the radial contrast by performing test recording and reproduction in the additional recording management area.
Further, it is preferable to record that the recording medium is a Low to High recording medium as guide groove information. In this case, it is common with the existing medium type discrimination operation.
In addition, the optical recording apparatus has acquisition means (for example, an interface) for acquiring content information via a network. Note that the acquisition unit may acquire content information from a portable storage medium such as a CD, DVD, or USB memory.
In addition, the content information can be efficiently recorded by reading the content information from the Internet or a portable recording medium and combined with the medium, the recording method, and the optical recording apparatus of the present invention, and has excellent reproduction compatibility. A content-recorded medium can be provided.

The content-recorded optical recording medium creation system according to the present invention has an optical recording device connected to a network. Then, the optical recording apparatus acquires the content information via the network, and acquires the content information with respect to the optical recording medium on which the above-described Low to High recording is performed by the optical pickup 13 while receiving control from the laser controller 19. The content information is recorded and the access area is recorded.
The content-recorded optical recording medium created by this system has a small push-pull signal after recording, as described above. For this reason, it contributes to a new business form considering copyright protection.
That is, recently, in a rental video store or the like, a business form of recording video content distributed over the Internet on a recordable DVD disc supplied from a distributor and renting it to a customer is considered. Yes. However, in the conventional High to Low type optical recording medium, when the customer tries to reproduce on the reproduction apparatus at home, reproduction is prohibited because the unauthorized reproduction is made. (The customer can not watch).

More specifically, in the DVD, CSS (Content Scramble System) is used as one of copyright protection methods. The DVD video content encrypted by CSS is normally present only on a read-only DVD disc. For this reason, when the playback device identifies the recordable DVD disc and the read-only DVD disc and determines that the recordable DVD disc is a recordable DVD disc, the playback device assumes that the copy has been illegally copied. The reproduction of the recorded CSS content can be prohibited. Here, the discrimination between the recordable DVD disc and the read-only DVD disc may be performed depending on the magnitude of the push-pull signal. Since the read-only DVD disc has no guide groove on the substrate, the push-pull signal is smaller than that of the recordable DVD disc having the guide groove. For this reason, when the detected push-pull signal is smaller than the predetermined value (in the first range), the playback device determines that the read-only DVD disc is used, and the detected push-pull signal is lower than the predetermined value. If it is large (within the second range), it is determined that it is not a read-only DVD disk (recordable DVD disk). Therefore, in the above-mentioned new business form, when recording on a conventional High to Low type optical recording medium, if the customer tries to play back on the playback device at home, although it was not illegally copied, Since the push-pull signal after recording is large, the disc is determined to be a recordable DVD disc.
On the other hand, when recording on the Low to High type optical recording medium according to the present invention, since the push-pull signal after recording is small, even when the customer plays back on the playback device at home, the playback-only DVD It is discriminated as a disc and can be viewed safely.

  According to the present invention, for an optical recording medium on which Low to High recording is performed at a DVD laser wavelength (640 to 680 nm), an optical recording apparatus capable of controlling recording conditions according to the optical characteristics, and a content recording additional recording Type optical recording medium creation system can be provided.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example 1)
A substrate 1 having a guide groove uneven pattern having a depth of about 300 mm, a groove bottom width of about 0.24 μm, and a track pitch of 0.74 μm on the surface of a polycarbonate disk having a diameter of 120 mm and a thickness of 0.6 mm is prepared. (A) is the cyanine dye of the following [Chemical Formula 9], and the dye material (B) is No. 8, a dithiol Ni complex of the following [Chemical Formula 10] as the light-resistant material (C), and a formazan chelate dye of the following [Chemical Formula 11] as the light-resistant material (D), in a weight ratio of A: B: C: D = 4. 5: 3: 1.5: 1 was dissolved in 2,2,3,3-tetrafluoropropanol to prepare a dye recording layer coating solution. The coating liquid was spin coated and further annealed at 90 ° C. for 15 minutes to form the dye recording layer 2.
The maximum light absorption wavelength of the dye material (A) was 728 nm, and the light absorption (Abs.) At this wavelength was 0.49. The maximum light absorption wavelength of the dye material (B) is 601 nm, the light absorption (Abs.) At this wavelength is 0.36, and the light absorption (Abs.) At the recording / reproducing wavelength of 650 nm is 0.37. It was.
Next, an Ag alloy (Ag—In alloy, weight ratio 99.5: 0.5) is provided to a thickness of about 1400 mm by sputtering using Ar as the sputtering gas on the dye recording layer 2 and reflected. Layer 3 was designated.
Further, a protective layer having a thickness of about 4 μm made of an ultraviolet curable resin (SD390 manufactured by Dainippon Ink and Chemicals, Inc.) is provided thereon to produce a disk body, and a dummy substrate 4 (cover substrate) made of polycarbonate having the same shape is prepared. A DVD + R optical recording medium was prepared by bonding with an ultraviolet curable resin adhesive (DVD 802 manufactured by Nippon Kayaku Co., Ltd.).
The guide groove was formed as a phase modulation wobble conforming to DVD + R.

About the said optical recording medium, the characteristic was evaluated based on the measurement conditions of the said DVD + R system specification using the optical disk evaluation apparatus ODU-1000 by a pulse tech company. Further, the following push-pull signal, radial contrast signal, difference signal, reflectance, signal modulation degree, and the like are measured by the method described in the system standard, and light absorption (Abs.), Maximum absorption peak wavelength is measured. Etc. were measured using a spectrophotometer (Hitachi Ratio Beam Spectrophotometer U-1000).
In the signal recording, a DVD (8-16) signal was recorded at a radial position of 23 to 24 mm under the conditions of wavelength: 659 nm, NA: 0.65, and linear velocity: 8X (27.92 m / s). As a recording condition, a castle pulse emission pattern according to the DVD + R standard was adopted. The pulse emission pattern used for recording is shown in FIG.
For signal reproduction, unrecorded and recorded signals were measured under the conditions of wavelength: 659 nm, NA: 0.65, and linear velocity: 1 × (3.49 m / s). The state of the reproduction signal is shown in FIG.
The results are shown in Table 2. In the recording mode column, “L to H” is an abbreviation for “Low to High”, and “H to L” is an abbreviation for “High to Low”.
The value in the column “PPa / PPb” is the ratio (%) of the push-pull signal (PPa) after recording to the push-pull signal (PPb) before recording (unrecorded).
As can be seen from Table 2, the optical recording medium of this example is a Low to High mode recording medium in which the reflectance of the recording portion increases after recording, and the reflectance of the unrecorded portion is in the range of 12 to 30%. In other words, it was confirmed that the unrecorded portion and the push-pull signal after recording were less than 0.3, and PPa / PPb was 79%.
In addition, it was 0.30 when the commercially available DVD-ROM disc was reproduced | regenerated with the same evaluation apparatus and the push pull signal was measured.

(Comparative Example 1)
A substrate 1 having a guide groove uneven pattern with a groove depth of about 1500 mm, a groove bottom width of about 0.24 μm, and a track pitch of 0.74 μm is prepared on the surface of a polycarbonate disk having a diameter of 120 mm and a thickness of 0.6 mm. As the material, the above No. No. 1 squarylium dye, the formazan chelate dye of the above [Chemical Formula 11] as a light-resistant material, in a weight ratio of No. 1 1: [Chemical Formula 11] = 7.5: 2.5 was dissolved in 2,2,3,3-tetrafluoropropanol to prepare a coating solution for the dye recording layer 2. Other conditions were the same as in Example 1, and a DVD + R optical recording medium was prepared and evaluated.
The results are shown in Table 2. The maximum light absorption wavelength of the dye material was 606 nm, the light absorption (Abs.) At this wavelength was 0.60, and the light absorption (Abs.) At a recording / reproducing wavelength of 650 nm was 0.13.
As can be seen from Table 2, the optical recording medium of this comparative example is a High to Low mode recording medium in which the reflectance of the recording part after recording is reduced, and the reflectance of the unrecorded part is 45% or more. It was confirmed that the non-recorded portion and the recorded push-pull signal were 0.3 or more, and that PPa / PPb was 135%.
Further, the recording sensitivity was poor, and the laser power required for recording was 20% or more higher than that in Example 1.
Therefore, the recording apparatus of the present invention uses at least one of a track error signal and a focus error signal as an optical recording medium on which Low to High recording is performed, in which the reflectance after recording is higher than the reflectance before recording of the recording mark portion. It is possible to determine that the signal is a write-once type optical recording medium on which Low to High recording is performed by detecting more than one type of signal. Based on the medium determination result, optimum recording / reproducing conditions (focus servo and Tracking servo, etc.) can be set, so it is possible to reduce servo failure defects during recording and playback, and there is no degradation in data recording and playback quality (jitter and data errors) due to focusing and tracking adjustment failures, resulting in excellent recording and playback performance. .

The figure which shows the light absorption spectrum of pigment | dye material. The figure which shows the layer structure of the optical recording medium of DVD + R and DVD-R. The figure which shows the layer structure of the optical recording medium of the reverse layer structure employ | adopted by BD-R. FIG. 3 shows a pulse emission pattern used for recording in Example 1. The figure which shows the condition of the reproduction signal of Example 1. FIG. 1 is a diagram illustrating a configuration example of an optical recording apparatus. The figure for demonstrating the outline | summary of discrimination | determination of a medium type.

Explanation of symbols

1 Substrate 2 Dye recording layer (optical recording layer)
3 Reflective layer 4 Dummy substrate 5 Light transmissive protective layer 6 Light transmissive cover layer space space mark mark T basic clock period n integer greater than or equal to n 'integer greater than or equal to 3 ps previous space length cm record mark length W1 3T mark Pulse power 4P or higher pulse power W2 4T or higher mark pulse power W4 Erase power Pc Cooling power

Claims (8)

  An optical recording apparatus capable of recording on an optical recording medium on which Low to High recording is performed at a DVD laser wavelength (640 to 680 nm), and detects a push-pull signal and / or a meandering frequency of a guide groove from a track error signal. An optical recording apparatus that records under control of recording conditions based on the detection result.   When the detection result of the push-pull signal is less than 0.3 and the detection result of the meandering frequency of the guide groove is “Yes”, it is determined that the recording medium is a write-once type optical recording medium on which Low to High recording is performed, 2. The optical recording apparatus according to claim 1, wherein recording conditions are controlled based on the determination result.   An optical recording apparatus capable of recording on an optical recording medium on which Low to High recording is performed at a DVD laser wavelength (640 to 680 nm), and detecting a push-pull signal and / or a meandering frequency of a guide groove from a track error signal, An optical recording apparatus, wherein a medium reflectance and / or the number of reflection surfaces are detected from a focus error signal or a reproduction signal, and recording is performed by controlling recording conditions based on the detection results.   When the push-pull signal detection result is less than 0.3, the medium reflectivity detection result in an unrecorded state is 12 to 30%, and the detection result of the number of reflection surfaces is one, Low to High 4. The optical recording apparatus according to claim 3, wherein the optical recording apparatus is determined to be a write-once type optical recording medium on which recording is performed, and recording is performed by controlling recording conditions based on the determination result.   5. The optical recording apparatus according to claim 2, wherein the optical recording apparatus discriminates that the medium is a write-once type optical recording medium on which Low to High recording is performed and a CSS content recording medium.   A write-once optical recording medium that controls reproduction conditions based on the controlled recording conditions, and further reads discrimination information relating to a medium recorded as Low to High recorded as a guide groove signal and performs Low to High recording or 6. The optical recording apparatus according to claim 1, wherein recording is performed after confirming that the medium is a CSS content recording medium.   The optical recording apparatus according to claim 1, further comprising means for acquiring content information via a network.   A system for creating a content-recordable write-once optical recording medium, comprising: the optical recording apparatus according to claim 2; and a server connected to the optical recording apparatus via a network. And means for acquiring the content information, and means for permitting recording of the acquired content information when it is determined that the recording medium is a write-once type optical recording medium on which Low to High recording is performed. System for creating a recordable write once optical recording medium.