JPH0369034A - Information storage medium and its manufacturing method - Google Patents

Abstract

PURPOSE:To allow stable optical recording with a high sensitivity with the information memory medium having a recording layer consisting of a high- polymer liquid crystal on a substrate by providing a thermocompression bondable laminated layer adjacently to the recording layer. CONSTITUTION:A reflecting layer 3 is provided on the substrate 1 formed with grooves for tracking on the surface and the recording layer 2 consisting of the high-polymer liquid crystal is formed thereon. The thermocompression bondable laminated layer 4 is provided adjacently to this layer 2 to form the information recording medium. The recording is executed by the phase change and orientation change of this layer 2. This layer 2 is oriented by the impression of heat and pressure. The uniaxial horizontal orientation is obtd. by impressing the pressure to this layer while moving the medium in one direction. The laminated film to be used has preferably <=200 deg.C glass transition temp. The uniaxially oriented stable optical recording is executed with the high sensitivity in this way without degrading the S/N by the domain wall of the high-polymer liquid crystal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an information storage medium that optically stores large amounts of data and a method for manufacturing the same, and particularly relates to a write-once information storage medium using polymeric liquid crystal. It is something.

[Prior Art] Optical storage systems are currently in practical use as they have a large capacity and are excellent in random access. There are many different ways to do this, and for playback only, digital audio discs (C
D) and laser video discs (LD) have been put into practical use. Write-once optical disc B is one that allows optical recording.
o) Optical cards (OC) are known, and some use a phase change of a metal thin film and others use an organic dye in the form of pits.

Furthermore, research on rewritable optical disks is progressing, and efforts are being made to put those using the magneto-optical effect and those using phase change into practical use. Among these, polymer liquid crystals have also been proposed as information storage media (Japanese Patent Application Laid-Open No. 10930-1983)
No. 1, JP-A-59-35989, JP-A-62-
154340). Among them, a recording method has been proposed in which the helical pitch length of the cholesteric polymer liquid crystal is changed or the light reflectance is multivalued by forming pits in an unoriented state (Japanese Patent Application Laid-Open No. 1983-1993).
2-107448, JP-A-62-12937).

In addition, as a simple method, a method has been proposed in which a polymer liquid crystal that has not been aligned is irradiated with a laser, heated to form an isokitic phase, and then rapidly cooled to below the glass transition point, thereby recording the isokichi phase in a fixed manner. .

(Japanese Unexamined Patent Publication No. 191673/1983) An information storage medium having such a polymeric liquid crystal as a recording layer does not require vapor deposition or the like, and can perform stable recording with high sensitivity.

[Problems to be Solved by the Invention] However, in an information storage medium having the polymer liquid crystal as a recording layer, it is possible to easily and inexpensively manufacture an information storage medium using a method that does not use orientation; Since the S/N ratio is greatly reduced due to the domain wall of the liquid crystal, there is a drawback that the reproduction device becomes complicated.

In addition, when an alignment film is provided on an information storage medium having a polymer liquid crystal as a recording layer and the alignment film is used for alignment, the formation of the alignment film is complicated, the manufacturing cost increases, and the alignment process takes time. Therefore, there was a drawback that productivity decreased.

On the other hand, there is a method of performing orientation processing using an electric field or magnetic field, but this method requires a strong electric field or magnetic field and has the disadvantage of low productivity because the orientation processing takes time.

The present invention has been made to improve the drawbacks of the prior art, and has been made to provide excellent uniaxial tree alignment treatment,
It is an object of the present invention to provide an information storage medium capable of performing highly sensitive and stable optical recording without deterioration of S/N due to domain walls of polymeric liquid crystals.

Another object of the present invention is to provide a method for manufacturing the information storage medium at low cost and efficiently.

[Means for Solving the Problems] That is, the present invention provides an information storage medium having a recording layer made of a polymeric liquid crystal on a substrate, which is characterized by having a thermocompression adhesive laminate layer adjacent to the recording layer. It is an information storage medium.

Further, the present invention provides an information storage characterized in that a film is thermocompression bonded and laminated on a recording layer made of polymeric liquid crystal formed on a substrate at a temperature equal to or higher than the glass transition point of the recording layer. This is a method for producing a medium.

The present invention will be explained in detail below.

FIG. 1 is a partial cross-sectional view showing an example of the information storage medium of the present invention. In the figure, the information storage medium of the present invention is provided with a reflective layer 3 on a substrate 1 on which groups for tracking are formed on the surface, and a recording layer 2 made of polymer liquid crystal on top of the substrate 1.
A thermocompression adhesive laminate layer 4 is provided adjacent to the recording layer.

In the present invention, polymer liquid crystal is used for the recording layer, and recording is performed by its phase change and orientation change.

Examples of polymeric liquid crystals used in the present invention include those shown below.

(In the following formulas (1) to (13), 15>n≧1.

)(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (14) (15) (16) (11) (12) (13) (In the following formulas (14) to (17), P: 1ooo to 5.

p++ p2= 5-1ooo.

q=1~12° Q+= 1~12° Q2= It is.

) l~12 (17) (In the following formulas (18) to (46).

* indicates asymmetric carbon center show, n=5 to 1000.

) (day,=2~10) (s,=2~10) (25) (Peng2=2~15) (26) (Peng2=2~!5) (-,=2~+5) (21 ) (m, = 2~15) (23) (24) ■ -+ (:)1. -C→-Ir' (29) (x+y=l, q=l ~to, Pa=1~15)
(30) (31) (32) l3 (x+y=1.dynamic=2~15) (>(+y=l, m2=2~Is) (37) (m,=1~5) (33) (s ,=2~15゜x+y=1) R,= CH3 -C)I2CH2C)I-+ CH2→-R,=+C1
□→- (x+ y= 1, 11.= 2~15) (38) (39) (x+y=1) (41) (42) (43) (44) (49) (50) (51) (52 ) (■5=0~5) (Hereinafter, Peng will be 1~18) (45) (46) (47) (48) (53) (54) (55) r (56) (59) CI .

(60) (57) (58) (f.

=5-18) The polymer liquid crystal can be used as a composition in combination with a low-molecular liquid crystal compound. The composition includes nematic phase, smectic phase, chiral nematic phase,
Chiral smectic phase.

Those having a discotic phase or the like are used, or preferably those having a nematic phase or a chiral nematic phase are used.

Furthermore, when writing and erasing are performed using laser light or the like, sensitivity can be improved by providing a laser light absorbing layer or adding a laser light absorbing compound to the polymeric liquid crystal layer. Examples of the laser light absorbing compound added to the polymer liquid crystal layer include those shown below.

(I22 =5~ta) Direct Red 28 Direct Violet 12 Direct Blue 1 Direct Blue Is Direct Blue 98 Direct Blue 151 0■ Direct Red 81 Di rect Yellow 44 Direct Yellow 12 Direct Orange :19 Disperse Red 0 U■ Disperse blue 14 C204″ ' AsF 6e cI!o,e Further, examples of laser light absorbing compounds suitable for the wavelength of the semiconductor laser include those shown below.

Specifically, phthalocyanines, naphthalocyanines,
Tetrabenzoporphyrins and other substituted and unsubstituted porphyrins are used.

Particularly effective examples include phthalocyanine and naphthalocyanine represented by the following general formula (I).

(General formula (I) middle code It is indicated by.

[However, RI~R2゜ is a hydrogen atom, number of carbon atoms is 4~20
represents a straight-chain or branched alkyl group, alkoxy group, alkenyl group, or a substituent selected from the following.

-S! QIQ2Q3 -　sq.

-coq.

C00Qs NQtQa (Q, ~Q6 represent a hydrogen atom, a linear or branched alkyl group or alkenyl group having 1 to 20 carbon atoms)
IM is Ge, Sn, transition metal, AR, Ca, In,
Alkaline earth metals, lanthanide metals, aftinide metals, and their oxides, halogen compounds, or alkoxy compounds) When performing optical recording, it is important to use a semiconductor laser with a wavelength from near infrared to red visible for recording and reproducing equipment. Miniaturization,
Naphthalocyanines are particularly excellent as soluble organic macrocyclic dyes that can be used in this wavelength range, which is important for improving performance.

In particular, those represented by the general formula (■) have excellent solubility and are therefore suitable for the storage medium of the present invention.

(X@n)b [M in general formula (n): Ge, Sn, transition metal, Aj), Ca,
In, alkaline earth metal, lanthanide metal or aftinide metal X: halogen group, alkyl group, carboxyl group, alkoxy group, ether group, alkenyl group, etc.

Xm1SXh: halogen group, alkyl group, sulfaceyl group, ether group, alkenyl group, etc. a-d: 0-4.

(However, a+b+c+d≧1),] These compounds can be easily synthesized by the method disclosed in JP-A-61-90291.

Furthermore, other compounds that can be used as absorbers for semiconductor laser light include achnium salt compounds and diimonium salt compounds.

The aminium salt compound and diimonium salt compound used in the present invention have the following general formulas [ml, [ff
It is represented by l and [V].

General formula [ml General formula [ff1 General formula [V] In the above general formulas [ml, [171 and [V]], R1-R3° are the same or different hydrogen atoms, or alkyl groups (e.g., methyl group, ethyl group). Base.

n-propyl group, 1so-propyl group, n-butyl group, 5ec-butyl group, 1so-butyl group, t-butyl group, n-amyl group, t-amyl group, n-hexyl group, n-
octyl, 7-octyl, and C9-Ctt alkyl groups), as well as other alkyl groups, such as substituted alkyl groups (e.g.

2-hydroxyethyl group, 3-hydroxypropyl group,
4-hydroxybutyl group, 2-acetoxyethyl group, carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 2-sulfoethyl group, 3-sulfopropyl group, 4-sulfobutyl group, 3-sulfatepropyl group , 4-sulfatebutyl group, N-(methylsulfonyl)-carbalmethyl group, 3-(acetylsulfamyl)propyl group, 4-(acetylsulfamyl)butyl group, etc.), cyclic alkyl group (e.g. , 'cyclohexyl group, etc.), alkenyl group (vinyl group, allyl group, propenyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, dodecynyl group, prenyl group, etc.), aralkyl group (for example, benzyl group, phenethyl group, α-naphthylmethyl group, β-naphthylmethyl group, etc.), substituted aralkyl groups (for example, carboxybenzyl group, sulfobenzyl group, hydroxybenzyl group, etc.).

Y represents + or -()-()i, and this aromatic ring may be substituted with an alkyl group, a halogen group, or an alkoxy group.

Ae is an anion, such as verchlorate, fluoroborate, iodide, chloride, bromide, sulfate, periodide, p-toluenesulfonate. These aminium salt compounds and diimonium salt compounds are described in Japanese Patent Publication No. 153-253-15. It can be synthesized according to the synthesis method disclosed in et al.

Furthermore, the following metal chelate compounds can be mentioned as absorbers for semiconductor lasers.

Examples of the metal chelate compounds used in the present invention are represented by the following general formulas [1] to [7].

General formula [1] (In the formula, Ls is a hydrogen atom, a hydroxyl group, an alkyl group, or an aryl group, and may be bonded to the other Ls e R
IB represents an alkyl group, a halogen atom, a hydrogen atom, a nitro group, or a benzo-fused group, and the central metal M is Cu, N
Represents i, Go or Pd. ) General formula [2] (Formula Φ, fl+y may be bonded to the other R1? with a hydrogen atom, hydroxyl group, alkyl group, or aryl group.

Rla represents a hydrogen atom, a halogen atom, an alkyl group, a nitro group, or a benzo-fused group, and M is Cu.

Represents Ni, Go or Pd. ) General formula [3] represents a hydrogen atom, a halogen atom, an alkyl group, or a benzo-fused group, and M is Cu. Represents Ni or Pd. ) General formula [5] (In the formula, RI9 is an alkyl group, the aryl group tLO is a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, or a benzo-fused group, and M is Cu, old or Pd
represents. > General formula [4] (In the formula, R2 represents a hydrogen atom, a halogen atom, or an alkyl group, and M represents Cu or Ni.) General formula [6
] 21 (wherein R24 represents a hydrogen atom or an alkyl group,
M represents Cu, Ni, Co or Mn. ) (wherein, R2+ is an alkyl group or an aryl group, and R22 is a general formula [
7] General formula [8] (In the formula, R2S+ L6 is a substituted or unsubstituted alkyl group, acyl group or aryl group, or R□, R26 may form an aromatic ring. 0M is Cu, Ni, Go (In this case, 1M has a charge and may have a counter ion.) The metal chelate compound has absorption in the near-infrared region, is useful as a stable light-absorbing dye, and is useful for polymer liquid crystals. It has good compatibility or dispersibility.

Furthermore, other compounds that can be used as absorbers for semiconductor laser light include the following compounds.

(In the formula, net represents a sulfur atom, a substituted or unsubstituted amino group, an oxygen atom or a thioketone group, R251 represents a hydrogen atom, an alkyl group, a halogen atom or an atom) group,
represents Zn, Cu or Ni) General formula [9] (In the formula, R29 represents an alkyl group, aryl group or styryl group, and 1M represents Cu, Ni or CO) General formula [lO] General formula [12] (In the formula, R30 represents a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an aryl group, and 1M represents Ni or Z.
General formula [11] (wherein R3□ and R33 are an alkyl group or an aryl group,
M represents Ni) General formula [13] (In the formula, R31 is an alkyl group or an aryl group, M is Cu
, represents Ni or Co. ) 0,70ゝH (In the formula, Fh4+ F125 is an alkyl group, an amino group,
An aryl group or a furan group, or R34 and R3s may form an alicyclic compound. M represents Ni. ) General formula [14] (In the formula, R36+ R:I9 is a hydrogen atom, an alkyl group, a halogen atom, or a nitro group, X is an oxygen atom or a sulfur atom, M is a former, and Y@ represents a quaternary ammonium cation.) General formula [16] (In the formula, R)Go R37 is a hydrogen atom, a halogen atom, or an alkyl group, X is an oxygen atom or a sulfur atom, and M is Ni.) General formula [15] (In the formula, R40 is an amino group, M is Cu, Ni, G
o or Pd) General formula [17] ・(In the formula, R41 is a hydrogen atom, a halogen atom, an alkyl group, an acyl group, a nitro group, or an alkoxyl group, and M is a Zn
, Cu, Ni or Go) used in the present invention are described by Barry B. Gray et al. in Journal of the American Chemical Society, Vol. 88, pp. 43-50 and 4870-4875. ,
or the Journal of the American Society by Schranzer and Maibeek et al.
It is synthesized according to the method described in Vol. 87, pp. 1483-1489.

The semiconductor laser compound has absorption in the near-infrared region,
It is useful as a stable light-absorbing dye and has good compatibility or dispersibility with polymeric liquid crystals. Some of them also have dichroism, and if these dichroism compounds are mixed into polymeric liquid crystals, thermally stable host-guest type memories and display media can be obtained.

Furthermore, the polymer liquid crystal may contain two or more types of the above-mentioned compounds.

Further, the above compound may be combined with other near-infrared absorbing dyes or dichroic dyes. Representative examples of near-infrared absorbing dyes that can be suitably combined include cyanine, merocyanine, phthalocyanine, tetrahydrocholine, dioxazine, anthraquinone, triphenodithiazine, xanthine, triphenylmethane, pyrylium, croconium, azulene, and triphenylamine. Examples include dyes such as.

Note that the amount of the above compound added to the polymer liquid crystal is expressed in weight%.
and about 0.1% to 20%, preferably 0.5 to 1O
% is good. The polymer liquid crystal used in the present invention is a polymer thermotropic liquid crystal, and uses a nematic, smectic, chiral smectic, or cholesteric phase as an intermediate phase.

Furthermore, in addition to the above-mentioned low-molecular-weight liquid crystal two dyes and pigments, ultraviolet absorbers, anti-oxidation agents, and the like can be added to the recording layer made of high-molecular liquid crystal in the present invention. A recording layer made of polymeric liquid crystal containing these compounds is formed on a substrate on which groups for tracking are formed.

Next, examples of groove shapes for tracking provided on the substrate are shown in FIGS. 4(a) to 4(d). Moreover, from the experimental results, the size of the groove illustrated in FIG. 5, that is, the depth of the groove a,
The land part width C of the groove where the groove converges, the depth a of the groove is O, OS
, 1~0.21&m, groove width 0.5 BN2.0
H, the radius C of the land part of the groove is 0.5 to 2.0, especially the depth a of the groove is 0.1←■ to 0.2g, the width of the groove is 0.
5 gm~1. OILta, the width C of the land portion of the groove is 1.
It was confirmed that 0 p, m to 2.0 gm is preferable. However, even if all three of the above conditions are not met.

Under the above conditions, the depth of the groove may be set at least within the above range.

The above grooves may be formed at the same time as forming the substrate, or a smooth substrate may be coated with ultraviolet curing resin or the like and then stamped.
The resin may be formed by closely contacting the resin and irradiating it with light or the like to harden the resin.

In the present invention, the substrate material is glass.

Metal, ceramic, plastic, etc. are used. Plastics are preferably used, specific examples being polyester, polyvinyl chloride, and PMMA.

Examples include PC and polyolefin.

The substrate having the grooves has AI! The reflective layer is formed of a metal such as , Au, or Ag or a dielectric multilayer film. The thickness of the reflective layer is preferably 100 to log■, and 1
If it is less than 0.00, a sufficient reflectance cannot be obtained, and if it exceeds 1.0, the heat capacity and thermal conductivity will increase and the sensitivity will decrease.

The above reflective layer can be formed by vapor deposition or the like.

To form the recording layer on the substrate, the polymeric liquid crystal composition containing the dye etc. is dissolved in a solvent and applied onto the substrate having the reflective layer using a spinner coating method, a dipping method, a barcoding method, or a roll coating method. Apply by law etc. In some cases, it is also possible to apply it to a laminate film.

The thickness of the recording layer made of polymer liquid crystal in the present invention is 10
00λ~50μs is preferable; less than 1000 people is not preferable due to poor reproduction contrast;
If the thickness exceeds μ, the recording energy increases and the recording pit diameter also increases, which is undesirable. A more preferable thickness is 1.
Used in 500 Å to 5 μ gardens.

The glass transition temperature of the polymeric liquid crystal used in the recording layer is at least room temperature, more preferably at least 50° C., so that recorded content can be maintained well.

Next, the method for manufacturing an information storage medium of the present invention includes laminating a film onto a recording layer made of polymeric liquid crystal formed on a substrate by thermocompression bonding at a temperature equal to or higher than the glass transition point of the recording layer. Specifically, a recording layer made of the above-mentioned polymeric liquid crystal is formed on a substrate or a laminate film, and the laminate film or substrate is brought into close contact with the laminate film or substrate by applying heat and pressure.

Heating is 1. The entire substrate or only the pressed portion may be heated to a temperature equal to or higher than the glass transition point of the recording layer. More preferably, a temperature is selected that is below the isotonic phase transition point of the recording layer and does not cause deterioration of the substrate, polymeric liquid crystal, and substrate film.

Specifically, 50 to 300°C, more preferably 60 to 300°C.
Laminate at 200°C. The recording layer made of polymer liquid crystal has a nematic phase and a chiral nematic phase.

It is laminated with a smectic phase, a chiral smectic phase, a discotic phase, etc., and more preferably a nematic phase or a chiral nematic phase.

The pressure applied in thermocompression bonding differs depending on the elasticity of the filler film, but for example, when a pressure roller is used, the linear pressure is 0.1 to 100100 O/c+s, preferably 1 to 100 gf/cm. .

The recording layer made of polymeric liquid crystal is oriented by the application of heat and pressure, and by applying pressure while moving in one direction, uniaxial tree-plane alignment can be obtained. The speed of movement depends on heat and pressure, but l cm
/m1rr-1oses/sec is used.

The laminate film used in the present invention preferably has a glass transition temperature of 200°C or lower, and preferably has a thickness of 0.01 to 2 mm. This laminate film is made of a transparent material with low birefringence, and Specifically, PMMA, polycarbonate, polyolefin, etc. are used.

In the method for manufacturing an information storage medium of the present invention, when a card-like or tape-like medium is used as the medium to be laminated, it is possible to laminate it while applying pressure and heating in one direction as shown in FIG. An oriented information storage medium is obtained.

In addition, when using a disk-shaped medium, an information storage medium in which polymeric liquid crystals are well oriented in concentric circles can be obtained by laminating the medium while rotating it and applying pressure and heat as shown in Figure 3. .

[Function J] The information storage medium of the present invention has a recording layer made of a polymeric liquid crystal on a substrate, and by providing a thermocompression adhesive laminate layer adjacent to the recording layer, domains of the polymeric liquid crystal can be formed. It is possible to prevent a decrease in S/N due to the wall and perform stable optical recording with high sensitivity.

In addition, one aspect of the present invention is to apply heat and pressure in one direction to a laminate film forming a laminate layer on a recording layer made of polymeric liquid crystal formed on a substrate at a temperature equal to or higher than the glass transition point of the recording layer. Since the film is laminated by thermocompression bonding by application of heat, an information storage medium whose recording layer is subjected to a good uniaxial planar orientation treatment can be obtained efficiently in a short time.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Groups with a depth of 62 mm and a width of 5 gm were formed using the injection method. Oi+m, 85x 5
A reflective layer was formed on a 5 m square card-shaped PMMA substrate by vapor depositing Af to a thickness of 2000 mm using an electron beam.

Next, a polymeric liquid crystal (I
) was dissolved in cyclohexane to a concentration of 15 wt%, and an IR absorbing dye represented by the following structural formula (n) was dissolved at a concentration of 1.2 wt%.

(I) (PST conversion by CPCE Mw = 15000
)75°C 114°C g-)N-)Iso.

(CJs) J-□

Next, the substrate was held at 100°C and passed through a pressure roller held at 120''C together with a laminate film made of a PC board having a thickness of 0.6 tam to obtain a card-shaped information storage medium.

The obtained card-shaped information storage medium had a reflectance of 35% at a wavelength of 830 nm. Recording was performed using a semiconductor laser with a wavelength of 8:1 Onm, and observation using a two-reflection polarizing microscope showed good uniaxial alignment, with no domain wall.
The contrast was 1:20.

Next, a 100 KHz recording (10 mW on the plate surface) was performed using an 830 nm, 40 mW semiconductor laser.
When reproduced at 0.5 mW, good recording and reproduction was possible at 48 dB with CAM.

Example 2 Diameter 1 of groups formed by injection method
Ai) was deposited to a thickness of 2,000 layers on a disk-shaped polycarbonate substrate with a thickness of 1.2 cm and 30 layers, and on top of that, a polymer liquid crystal represented by the following structural formula (m) was coated with the following structural formula (Ilir). ) is 1, Owt.
% and dissolved in cyclohexane was coated using a spinner, and after drying, a recording layer made of polymeric liquid crystal having a thickness of 11 Lm was formed.

(■) (GPC!; 1m PST conversion My = 1000
0) 50°C 120°C g-) N -1 → Iso Next, a PMMA film with a thickness of 0.6 gm was laminated on the substrate, and as shown in Figure i3, it was held on a heated roller at 130'C. When pressurized while rotating, a uniformly oriented information storage medium without domain walls was obtained in concentric circles.

830r from the laminated film side to this information storage medium.
Using a v+ semiconductor laser, beam diameter 2 μm, disk rotation speed 500 rpm, 500 KHz, 20 m
When W"t' was recorded and reproduced at 1-, the C/N during reproduction was as good as 48 dB. The resolution bandwidth of spectrum analysis of the reproduced waveform at this time was 30 KHz.

[Effects of the Invention] As explained above, according to one aspect of the present invention, in an information storage medium having a recording layer made of a polymer liquid crystal on a substrate, by providing a thermocompression adhesive laminate layer in contact with PIi to the recording layer, , S/ by polymer liquid crystal domain wall
It is possible to obtain a uniaxially oriented information storage medium capable of performing highly sensitive and stable optical recording without a decrease in H.

In addition, a laminate film forming a laminate layer is thermocompression bonded onto a recording layer made of polymeric liquid crystal formed on a substrate by applying heat and pressure in one direction at a temperature higher than the glass transition point of the recording layer. By laminating them, an information storage medium whose recording layer has been subjected to a good uniaxial tree-plane orientation process can be obtained efficiently and at low cost.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view showing an example of the information storage medium of the present invention, FIG. 2 is an explanatory diagram showing a lamination method for card-shaped and tape-shaped information storage media, and FIG. 3 is a lamination method for disk-shaped information storage media. 4(a) to Cd) are schematic cross-sectional views of the groove shape of the substrate, and FIG. 5 is an explanatory view showing the size of the groove shape of the substrate. l... Substrate 2... Recording layer 3... Reflective layer 4... Protect layer 4a... Protect film 5... Heat/pressure application roll 6... Groove Fig. 1

Claims (6)

[Claims] (1) An information storage medium having a recording layer made of polymeric liquid crystal on a substrate, characterized in that the information storage medium has a thermocompression adhesive laminate layer adjacent to the recording layer. (2) The information storage medium according to claim 1, wherein the laminate layer has a glass transition point of 200°C or lower. (3) Claim 1, wherein the polymer liquid crystal is horizontally uniaxially aligned.
Information storage medium as described. (4) The information storage medium according to claim 1, wherein the polymer liquid crystal has a nematic phase. (5) A method for manufacturing an information storage medium, which comprises laminating a film on a recording layer made of polymeric liquid crystal formed on a substrate by thermocompression bonding at a temperature equal to or higher than the glass transition point of the recording layer. . (6) The method for manufacturing an information storage medium according to claim 5, wherein the thermocompression bonding is carried out by applying pressure while moving in one direction.