JP5158923B2 - Photocurable transfer sheet, method for producing optical information recording medium using the same, and optical information recording medium - Google Patents

Description

  The present invention relates to an optical information recording medium in which information such as DVD (Digital Versatile Disc) and CD (Compact Disc) is recorded and / or recordable as digital signals such as large-capacity characters, sounds, and moving images. The present invention relates to a method and a photocurable transfer sheet advantageously used in these methods.

  Audio CDs and CD-ROMs have been widely used as recorded optical information recording media (optical discs) with pits formed on the surface as digital signals. Recently, however, pits are provided on both sides where both moving images and recording are possible. Recorded DVDs are used as next-generation recording media for CDs, and the amount of use is expanding. Also, CD-R, CD-RW, DVD-R, DVD-RW, etc., which can be recorded by a user in which pits and grooves are formed, are widely used.

  On February 10, 2002, the next generation optical disc unified standard “Blu-ray Disc” was proposed as an optical disc capable of higher density recording. The main specifications are recording capacity: 23.3 / 25/27 GB, laser wavelength: 405 nm (blue-violet laser), lens numerical aperture (N / A): 0.85, disc diameter: 120 mm, disc thickness: 1.2 mm Track pitch: 0.32 μm or the like.

  As described above, the blu-ray disc has a narrow groove and a small pit. For this reason, it is necessary to narrow down the spot of the reading laser. However, if the spot is made smaller, it will be greatly affected by the tilt of the disc, and even if the DVD to be reproduced is slightly bent, it cannot be reproduced. In order to compensate for this disadvantage, it is considered to reduce the thickness of the substrate and to make the thickness of the cover layer on the pit on the laser irradiation side about 0.1 mm.

  Non-Patent Document 1, page 68 describes a DVD manufacturing method that meets the above requirements. This will be described with reference to FIG. A polycarbonate stamper having a reflective layer (or recording layer) 6a on a concave / convex surface provided with a UV curable resin 5A on the reflective layer of the disk substrate (1.1mm) 4a, and having a reflective layer (or recording layer) on the concave / convex surface. An ultraviolet curable resin 5B is provided on 4b by coating. Next, the substrate is turned upside down, the substrate and the stamper are attached, and ultraviolet rays are irradiated from the stamper side to cure the ultraviolet curable resins 5A and 5B. The stamper 4b is removed from the layer of the ultraviolet curable resin 5B, a reflective layer (or recording layer) 6b is formed on the uneven surface, and a cover layer (thickness of about 0.1 mm) 7 is formed thereon.

  In the above method, an ultraviolet curable resin is provided on the surfaces of the disk substrate and the stamper by coating, and then the substrate is turned upside down and attached to the stamper. In this way, it is necessary to perform a complicated process of application and inversion, and when pasting the substrate and the stamper by inversion, there are disadvantages such as the generation of bubbles when contacting the viscous UV curable resins, There is a problem that good pasting cannot be performed. Further, the ultraviolet curable resin has a large shrinkage at the time of curing, and there is a problem that deformation such as warpage of the obtained medium is conspicuous.

A method of manufacturing an optical information recording medium such as a DVD that can improve the above-described problems is disclosed in Japanese Patent Application Laid-Open No. 2003-115130. Here, a production method using a photocurable transfer sheet made of a photocurable composition containing a reactive polymer having a photopolymerizable functional group and deformable by pressurization is described. Further, Patent Document 2 (Japanese Patent Application Laid-Open No. 2003-123332) also describes a stamper of a copolymer of an acrylate ester having a curable group having a storage elastic modulus of 10 ³ to 10 ⁶ Pa before curing, as described above. An optical disc manufacturing sheet (photo-curable transfer sheet) having a receiving layer is disclosed. In the optical disc manufacturing, irregularities are formed on a demand layer with a stamper, a reflective layer is formed by metal deposition, and then a reflective layer is formed. When providing a protective layer on the layer, a pressure sensitive adhesive is used.

  As described above, the above-mentioned problem can be avoided by transferring the concavo-convex surface by pressing the stamper using the solid photocurable transfer sheet instead of the ultraviolet curable resin.

JP 2003-115130 A JP 2003-123332 A NIKKEI ELECTRONICS, No. 2001.1.5

  According to the study by the present inventors, when an optical disc is produced using the photocurable transfer sheet as described above, the warp of the medium and the thickness unevenness are improved, but the stamper is pressed against the photocurable transfer sheet, When the stamper was peeled off after being cured, it was found that a part of the photocured transfer layer of the photocurable transfer sheet may peel off from the reflective layer and adhere to the stamper. When such peeling of the transfer layer occurs, the uneven portion on the surface of the cured transfer layer, which is the recording surface, is damaged, and accurate signal reading by laser light becomes impossible. The main cause of such peeling of the transfer layer is that the adhesion between the transfer layer and the reflective layer is not sufficient, and in some cases, the adhesion between the photo-curing transfer layer and the stamper is considered to be too large. It is done.

  In addition, the optical disk is provided with a reflective layer on the uneven surface formed as described above on the photocurable transfer sheet, and a protective layer is provided via an adhesive. It has been clarified that peeling may occur between the transfer layer and the reflective layer or between the adhesive and the reflective layer when used in a severe environment such as high humidity. When such peeling occurs, the laser beam is diffusely reflected at the peeling portion, so that accurate signal reading by the laser light may not be possible.

  Accordingly, the present invention is a photocurable transfer sheet that is advantageous for the production of a high-capacity optical information recording medium such as a DVD, and is cured when the transfer sheet is cured during the production of the optical information recording medium. Photo-curing in which the transfer layer of the transfer sheet is excellent in adhesiveness with a reflective layer such as a silver alloy and can be easily peeled off from the stamper, so that an accurate shape of the concavo-convex signal surface such as pits can be easily obtained. It is an object to provide an adhesive transfer sheet.

  The present invention also relates to a photo-curable transfer sheet that is advantageous for manufacturing a thin optical information recording medium having a small thickness and high capacity such as a DVD, and is capable of transferring pits and the like when the optical information recording medium is manufactured. Further, when this transfer sheet is cured, the transfer layer of the cured transfer sheet is excellent in adhesiveness with a reflective layer such as a silver alloy and can be easily peeled off from the stamper. It is an object of the present invention to provide a photocurable transfer sheet in which an accurate shape of an uneven signal surface such as a pit can be easily obtained, and the obtained optical information recording medium can be used stably for a long period of time.

  It is another object of the present invention to provide a method for manufacturing an optical information recording medium having an accurate concave-convex signal surface such as the pit, almost no reading error, and excellent in durability.

  It is another object of the present invention to provide an optical information recording medium having an accurate concave-convex signal surface such as the pit, almost no reading error, and excellent durability.

The above purpose is
A photocurable transfer sheet having a photocurable transfer layer made of a photocurable composition that can be deformed by pressurization,
The photocurable composition has the following formula (1) or (2):

[However, R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms , and at least one of R ¹ and R ² is a hydrogen atom,
R ³ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms ,
R ⁴ represents an alkylene group having 1 to 20 carbon atoms , or an alkylene group having 2 to 20 carbon atoms having an ether bond, ester bond, siloxane bond or phenylene group in the middle , and Z represents methacryloyloxy Represents a group, acryloyloxy group, 4-vinylbenzyloxy group, styryl group, allyloxy group or allyl group . ]
A photocurable transfer sheet comprising a thiouracil derivative represented by:
Achieved by:

  Preferred embodiments of the photocurable transfer sheet of the present invention are as follows.

  1) A photocurable composition contains a polymer and a reactive diluent having a photopolymerizable functional group. It is easy to appropriately change physical properties such as Tg and elastic modulus of the composition, and transfer properties and the like can be improved.

2) The thiouracil derivative is represented by the following formula (3) or (4):

[However, R ⁵ and R ⁶ each represent a hydrogen atom or an alkyl group, and at least one of R ⁵ and R ⁶ is a hydrogen atom,
R ⁷ represents a hydrogen atom, an alkyl group or a phenyl group,
R ⁸ is a divalent saturated hydrocarbon group having 2 to 12 carbon atoms, —CH ₂ —C ₆ H ₄ —CH ₂ — or — (CH ₂ ) _O —Si (CH ₃ ) ₂ OSi (CH ₃ ) ₂ — (CH ₂ ) _P — (wherein o and p are each independently an integer of 1 to 5),
Y represents —COO—, —CH ₂ O— or —C ₆ H ₄ —CH ₂ O—, and R ⁹ represents a hydrogen atom or a methyl group. ]
It is represented by

3) In the above formula (3) or (4),
R ⁵ , R ⁶ and R ⁷ represent a hydrogen atom,
R ⁸ represents a divalent saturated hydrocarbon group having 2 to 12 carbon atoms,
Y represents —COO—, —CH ₂ O— or —C ₆ H ₄ —CH ₂ O—, and R ⁹ represents a hydrogen atom or a methyl group.

  Light in which the stamper is in close contact with a photocurable composition containing the thiouracil derivative represented by the formula (1) or (2) of the present invention, particularly the specific thiouracil derivative defined by the above 2) to 4). The photocured transfer layer of the curable transfer sheet exhibits excellent adhesion to a reflective layer such as a silver alloy (AgX (X: preferably Cu · Pd or Cu · Nd)), and is a stamper made of Ni or the like. Therefore, a part of the cured transfer layer is hardly peeled off from the reflective layer and attached to the stamper. Therefore, since the uneven shape on the surface of the cured transfer layer, which is the recording surface, remains accurately on the reflective layer as it is transferred, it is possible to read a signal with a laser beam without error. Further, the durability of the obtained optical information recording medium is also improved by such excellent adhesion between the reflective layer and the transfer layer.

4) The glass transition temperature of the photocurable transfer layer after irradiation with ultraviolet rays of 300 mJ / cm ² is 65 ° C. or higher. By irradiating with ultraviolet rays for a short time, it is easy to prevent the occurrence of sagging such as a pit shape that is likely to occur due to residual stress during transfer, and the transferred pit shape can be retained.

5) The glass transition temperature of the photocurable composition is less than 20 ° C. It is easy to obtain excellent transferability.

6) A polymer having a glass transition temperature of 80 ° C. or higher is an acrylic resin.

7) The acrylic resin is an acrylic resin containing at least 50% by mass of repeating units of methyl methacrylate. Appropriate combination with a reactive diluent makes it easy to achieve both good transferability and excellent curability.

8) The acrylic resin is an acrylic resin having a photopolymerizable functional group.

9) The acrylic resin is a copolymer of methyl methacrylate, at least one kind of (meth) acrylic acid ester having an alcohol residue of 2 to 10 carbon atoms, and glycidyl (meth) acrylate, and It is obtained by reacting a glycidyl group with a carboxylic acid having a photopolymerizable functional group. Appropriate combination with a reactive diluent makes it easy to achieve both good transferability and excellent curability.

10) A copolymer of an acrylic resin, methyl methacrylate, at least one kind of alkyl (meth) acrylic acid ester having an alcohol residue of 2 to 10 carbon atoms, and a carboxylic acid having a photopolymerizable functional group And obtained by reacting the carboxylic acid group with glycidyl (meth) acrylate. Appropriate combination with a reactive diluent makes it easy to achieve both good transferability and excellent curability.

11) The acrylic resin is an acrylic resin having a hydroxyl group.

12) The above acrylic resin having a hydroxyl group is methyl methacrylate, at least one kind of alkyl (meth) acrylate ester having 2 to 10 carbon atoms as an alcohol residue, and carbon having an alcohol residue as a hydroxyl group. It is a copolymer with at least one kind of alkyl (meth) acrylic acid ester having 2 to 4 atoms. It is particularly preferable to have 50% by mass or more of methyl methacrylate. Appropriate combination with a reactive diluent makes it easy to achieve both good transferability and excellent curability.

13) Further contains polyisocyanate (preferably diisocyanate). Post-crosslinking before photocuring is possible, and the shape retention of the film before transfer is improved.

14) The number average molecular weight of a polymer having a glass transition temperature of 80 ° C. or higher is 100,000 or more and / or the weight average molecular weight is 100,000 or more. In particular, the number average molecular weight is preferably 100,000 to 300,000 and the weight average molecular weight is preferably 100,000 to 300,000. By making the molecular weight, the composition of the acrylic resin, and the ratio of the reactive diluent suitable as described later, particularly excellent transferability and high curing rate can be obtained.

15) The reactive diluent includes a compound having at least one hydroxyl group and at least two groups selected from acryloyl group and methacryloyl group. Adhesion between the reflective layer and the transfer layer is particularly excellent.

16) A photocurable composition contains 0.1-10 mass% of photoinitiators.

17) The light transmittance in the wavelength region of 380 to 420 nm is 70% or more.

18) The light transmittance in the wavelength region of 380 to 800 nm is 70% or more.

19) The thickness of the photocurable transfer layer is 5 to 300 μm.

20) A release sheet is provided on one or both surfaces of the photocurable transfer layer.

21) The photocurable transfer sheet has a long shape, and the photocurable transfer layer and the release sheet have substantially the same width.

The present invention includes the following steps (2) to (4):
(2) When the above-mentioned photocurable transfer sheet has a release sheet on both sides, the step of removing one of the release sheets;
(3) Photocuring of the photocurable transfer sheet on the reflective layer of the substrate having irregularities as recording pits and / or grooves on the surface and further provided with a reflective layer along the irregularities of the irregular surface. and mounting location so that the surface of sexual transfer layer in contact with the uneven surface of the reflective layer, those the presses laminate surface of the photocurable transfer sheet is in close contact along the uneven surface of the reflective layer A step of forming; and (4) a step of removing the other release sheet from the laminate.
There is also a method for manufacturing an optical information recording medium characterized by including:

  Preferred embodiments of the production method of the present invention are as follows.

1) Before the step (2),
(1) A step of punching a photocurable transfer sheet into a disc shape; or (1) A step of punching out the photocurable transfer layer of the photocurable transfer sheet and one release sheet into a disc shape, and leaving the other release sheet as it is. ;
I do.

2) After performing the step (4), further (5) a stamper having irregularities as recording pits and / or grooves on the surface of the photocurable transfer layer from which the release sheet of the laminate has been removed, step uneven surface is the mounting location so as to contact the surface of the transfer layer, to form a these are pressed laminate surface of the photocurable transfer sheet is in close contact along the uneven surface;
(6) A step of providing irregularities on the surface of the photocurable transfer layer by curing the photocurable transfer layer of the laminate having the stamper by ultraviolet irradiation and then removing the stamper;
including.

3) The ultraviolet ray irradiation of (6) is performed at at least 300 mJ / cm ² . Curing in a short time is possible.

  4) The glass transition temperature of the photocurable transfer layer obtained in the above (6) is 65 ° C. or higher.

5) After performing the steps (5) to (6), (7) a step of providing a reflective layer on the uneven surface of the photocurable transfer layer;
including.

  Furthermore, the present invention also resides in an optical information recording medium obtained by the above manufacturing method.

Furthermore, the present invention is also in the following optical information recording medium:
That is, the reflection is formed on the reflective layer of the substrate having irregularities as recording pits and / or grooves on the surface and further provided with a reflective layer (including a semitransparent reflective layer) along the irregularities of the irregular surface. An optical information recording medium comprising a cured layer of a photocurable composition provided so as to contact the uneven surface of the layer,
An optical information recording medium, wherein the photocurable composition is a composition of the photocurable sheet;
On the surface of the optical information recording substrate having irregularities as recording pits and / or grooves and further having a reflective layer formed on the irregular surface, irregularities as recording pits and / or grooves are formed on the surface. An intermediate resin layer having a reflective layer formed on the uneven surface, the surface of the intermediate resin layer having no unevenness facing the reflective layer on the substrate surface, An optical information recording medium provided along the unevenness,
An optical information recording medium, wherein the intermediate resin layer is a cured layer of the photocurable transfer layer of the photocurable transfer sheet; and the surface has irregularities as recording pits and / or grooves, and Intermediate resin having an irregular surface as recording pits and / or grooves on the reflective layer of the optical information recording substrate having a reflective layer formed on the irregular surface, and further having a reflective layer formed on the irregular surface A layer is provided on the reflective layer of the substrate surface with the surface having no irregularities of the intermediate resin layer facing the reflective layer of the substrate surface along the irregularities, and further having an irregular surface and a reflective layer Another intermediate resin layer as described above is provided on the reflective layer of the intermediate resin layer already provided on the reflective layer of the intermediate resin layer so that the surface having no irregularities of the intermediate resin layer faces the reflective layer of the intermediate resin layer already provided. Provided along An optical information recording medium,
An optical information recording medium, wherein the intermediate resin layer is a cured layer of a photocurable transfer layer of the photocurable transfer sheet.

  The photocurable transfer sheet of the present invention is a photocurable transfer sheet that is advantageous for the production of a high capacity optical information recording medium, such as a DVD, and has a pit or the like when the optical information recording medium is produced. Excellent in transferability and curability, and when this transfer sheet is cured, the transfer layer of the cured transfer sheet is excellent in adhesiveness with a reflective layer such as a silver alloy and is easily peeled off from the stamper. Therefore, it is easy to obtain an accurate shape of the uneven signal surface such as a pit. Furthermore, the adhesion between the transfer layer of the obtained optical information recording medium and the reflective layer such as a silver alloy is extremely good, and the transfer layer can be used regardless of whether the medium is used under severe conditions or for a long period of time. No peeling between reflective layers.

  Therefore, in the obtained optical information recording medium of the present invention, a part of the cured transfer layer is not peeled off from the reflective layer such as a silver alloy, and does not adhere to the stamper. In a state where the corresponding shape is accurately transferred, it is left on the surface of the reflective layer, and the adhesion between the reflective layer and the transfer layer is particularly excellent. For this reason, the optical information recording medium thus obtained has almost no reading error and is excellent in durability when a signal is read with a laser beam.

  In addition, since the rapid processing can be performed as described above by using the photocurable transfer sheet of the present invention, an optical information recording medium with high accuracy can be manufactured at high speed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of a photocurable transfer sheet 10 used in the present invention. The photocurable transfer layer 11 has release sheets 12a and 12b on both sides. The release sheet may be either one or not. It is set as appropriate according to the usage.

  The photocurable transfer layer 11 is a layer that is easily deformed by pressure so that it can be accurately transferred by pressing the uneven surface of the stamper, and has good adhesion to a reflective layer such as a silver alloy after curing. Thus, it is a layer excellent in the peelability of the stamper. That is, the photocurable transfer layer 11 is composed of a photocurable composition (generally containing a polymer and a reactive diluent having a photopolymerizable functional group), and the photocurable composition is represented by the formula (1). Or a specific thiouracil derivative represented by (2). By using this specific triazine derivative, the transfer layer of the photocurable transfer sheet photocured in a state where the stamper is in close contact with the silver alloy (AgX (preferably Ag · Cu · Pd (97.4: 0.9: 1.7 (mass)). Ratio)) [for example, APC manufactured by Furuya Metal Co., Ltd.] or Ag · Cu · Nd (98.4: 0.7: 0.9 (mass ratio)) [eg ANC manufactured by Kobelco Research Institute, Inc.])) In addition to exhibiting excellent adhesiveness, the surface of the cured transfer layer is easily peeled off from the stamper (generally nickel). For this reason, a part of the cured transfer layer is hardly peeled off from the reflective layer and attached to the stamper. Therefore, since the uneven portion on the surface of the cured transfer layer, which is the recording surface, remains accurately on the reflective layer while being transferred, it is possible to read a signal with a laser beam without error. Further, since the adhesion between the cured transfer layer and the reflective layer is extremely excellent, the durability of the obtained optical information recording medium is also excellent. The excellent adhesion of the transfer layer thus cured to the reflective layer is that the specific thiouracil derivative of the present invention has a higher affinity for the silver alloy of the reflective layer than Ni as the stamper material. It is considered that. In other words, since Ni is a base metal, it is in various stable oxidation states on the surface, but Ag exists because it is a precious metal and is hardly oxidized. The specific thiouracil derivative of the present invention has an affinity for such Ag. It is considered that it exhibits excellent adhesion with Ag because of its high properties.

  In the present invention, the photocurable composition preferably contains a polymer having a glass transition temperature of 80 ° C. or higher as the polymer. Accordingly, the uneven shape on the stamper or the substrate can be easily transferred, and the subsequent curing can be performed at a high speed. Further, since the cured shape also has a high Tg, the shape can be maintained for a long time without changing. As a polymer having a glass transition temperature of 80 ° C. or more, having a photopolymerizable functional group is advantageous in speeding up curing because it can react with a reactive diluent. In addition, by including a diisocyanate in the transfer layer 11 by having a hydroxyl group, it is possible to slightly crosslink the polymer, and in particular, a layer in which the transfer layer oozes out and the layer thickness fluctuation is greatly suppressed can be obtained. It is advantageous. Diisocyanates are effective to some extent even in polymers without hydroxyl groups.

  The photocurable transfer sheet preferably has a light transmittance of 70% or more in a wavelength region of 380 to 420 nm so that the information can be read with a reproducing laser in order to increase the density of information. In particular, the light transmittance in the wavelength region of 380 to 420 nm is preferably 80% or more. Therefore, the optical information recording medium of the present invention produced using this transfer sheet can be advantageously used in a method of reproducing a pit signal using a laser having a wavelength of 380 to 420 nm.

  Using the photocurable transfer sheet 10, the optical information recording medium of the present invention can be produced, for example, as shown in FIG.

  The photocurable transfer sheet 10 is first punched into a disk shape. At this time, when the photocurable transfer layer 11 and all of the release sheets 12a and 12b on both sides are punched out (generally in the case of full edge), the photocurable transfer layer 11 and one release sheet 12b are punched into a disk shape, and the other There is a case where the release sheet 12a is left as it is (generally a dry edge), which is appropriately selected (1). As described above, the punching operation in advance can be performed with good workability without using the photocurable transfer sheet of the present invention without causing the transfer layer to ooze out or protrude.

  Next, the release sheet 12a is removed from the photocurable transfer sheet 10, and a photocurable transfer layer with the release sheet 12b is prepared (2). Photo-curing with the side without the release sheet facing the translucent reflective layer 23a (generally a reflective layer having a relatively low reflectance such as AgX) of the irregular surface of the substrate 21 having irregularities as recording pits on the surface. The transfer sheet 10 is pressed (3). This forms a laminate (11, 23a, 21) in which the surface of the photocurable transfer sheet is in close contact with the uneven surface of the translucent reflective layer 23a. When used as an optical information recording medium with this configuration, the photocurable transfer sheet 11 is cured by ultraviolet irradiation, and the release sheet 12b is removed (4).

Next, a stamper 24 having irregularities as recording pits on the surface is pressed against the surface of the uncured photocurable transfer layer 11 (the surface not in contact with the substrate) by removing the release sheet 12b from the laminate. (5). A laminate (21, 23a, 11, 24) in which the surface of the photocurable transfer layer 11 is in close contact with the uneven surface of the stamper 24 is formed, and the photocurable transfer sheet of the laminate is irradiated with ultraviolet rays (generally, (6) After curing (300 mJ / cm ² or more), the stamper 24 is removed to provide irregularities such as recording pits on the surface of the cured sheet. As a result, a laminate (optical information recording medium) including the substrate 11, the reflective layer 23a, and the cured photocurable transfer layer 11a is obtained. In the present invention, when the stamper is removed, the cured transfer layer remains on the reflective layer without adhering to the stamper, and an uneven shape corresponding to the unevenness of the stamper is accurately formed on the surface of the transfer layer. Usually, a reflective layer (generally a reflective layer having a high reflectivity such as Al) 23b is provided on the unevenness (surface of the cured sheet) (7), and an organic polymer film (cover layer) 26 is further provided thereon as an adhesive layer. (8). As a result, the optical information recording medium shown in FIG. 3 is obtained. A photocurable transfer sheet may be further pressed on the surface of the cured sheet having recording pits, and cured by ultraviolet irradiation (generally 300 mJ / cm ² or more). Alternatively, an ultraviolet curable resin may be applied and cured on the surface of the cured sheet. The translucent reflective layer may be a normal reflective layer such as Al (for double-sided readout). Alternatively, the semitransparent reflective layer 23 may be a high reflectance reflective layer, and the high reflectance reflective layer 26 may be a semitransparent reflective layer. Furthermore, the stamper may be a substrate having irregularities.

  Further, by providing a translucent reflective layer instead of the highly reflective layer in the step (7) and repeating the steps (2) to (7), three or more recording pits can be formed. For example, an optical information recording medium having a four-layer structure as shown in FIG. 4 can be formed. This configuration is particularly attracting attention as the next-generation Blu-ray disc. That is, a substrate 21 having an uneven surface, a reflective layer 23a having an uneven surface, a photocurable transfer layer (intermediate resin layer) 11a cured on the reflective layer 23a having an uneven surface, Reflective layer (in general, a reflective layer having a higher reflectance than the previous reflective layer 13a) 23b provided on the irregularities, and a cured photocurable transfer layer (intermediate resin layer) having irregularities on the surface provided on the reflective layer 23b 11b, a reflective layer 23c formed thereon (a reflective layer having a higher reflectance than the previous reflective layer 23b), a cured photocurable transfer layer (intermediate resin layer) having irregularities on the surface provided on the reflective layer 23c ) 11c, and a reflective layer 23d formed thereon (a reflective layer having a higher reflectance than the previous reflective layer 23c). On the reflective layer 23d, an organic polymer film (cover layer) 26 or the like is attached as described above.

  In the above method, the read-only optical information recording medium has been described. However, the same can be applied to a recordable optical information recording medium. In the case of a recordable medium, it has a groove or a groove and a prepit. In this case, instead of the reflective layer and the translucent reflective layer, a metal recording layer (in the case of a dye recording layer or when the reflectance of the metal recording layer is low, In general, a recording layer and a reflective layer) and other functional layers (eg, an enhancement layer) are provided. Otherwise, the optical information recording medium can be manufactured in the same manner as described above.

  In the present invention, the concavo-convex shape which is a recording pit and / or a groove is pressed against the photocurable transfer layer 11 and the substrate 21 at a relatively low temperature (preferably normal temperature) of 100 ° C. or less (preferably under reduced pressure). The photo-curable transfer sheet is designed so that it can be transferred more accurately. Superposition of the substrate 21 and the photocurable transfer layer 11 is generally performed with a pressure roll or a simple press (preferably under reduced pressure). Further, the cured layer of the photocurable transfer layer 11 has a good adhesive force with the metal used for the reflective layer on the surface of the substrate 21 and does not peel off. If necessary, an adhesion promoting layer may be provided on the reflective layer.

  In the present invention, the concave and convex shapes that are recording pits and / or grooves are accurately determined by pressing the photocurable transfer layer 11 and the stamper 24 at a low temperature (preferably normal temperature) of 100 ° C. or less (preferably under reduced pressure). A photo-curable transfer sheet is designed to be transferred to the sheet. The stacking of the stamper 21 and the photocurable transfer sheet 11 is generally performed by a pressure roll or a simple press (preferably under reduced pressure). Further, the cured layer of the photocurable transfer layer 11 is generally a layer having a Tg of 65 ° C. or higher (particularly 80 ° C. or higher), and has a very weak adhesive force with a metal such as nickel used for a stamper. The photosensitive transfer sheet can be easily peeled from the stamper.

  Since the substrate 21 is generally a thick plate (usually about 0.3 to 1.5 mm, particularly about 1.1 mm), it is generally produced by a conventional injection molding method. However, you may manufacture using a photocurable transfer sheet and a stamper. Since the photocurable transfer sheet of the present invention can be thinned to 300 μm or less (preferably 150 μm or less), the other substrate can be produced by a conventional method, and the thickness of the substrate can be increased. Transfer accuracy can be increased.

  In the above step, when pressing the photocurable transfer layer against the substrate or when pressing the stamper against the photocurable transfer layer, it is preferable to press under reduced pressure. Thereby, the removal of bubbles and the like are performed smoothly.

  The pressing under reduced pressure may be performed, for example, by passing a photocurable transfer sheet and a stamper between two rolls under reduced pressure, or using a vacuum forming machine, placing the stamper in a mold and reducing the pressure. Examples thereof include a method in which a photocurable transfer sheet is pressure-bonded to a stamper.

  In addition, pressing under reduced pressure can be performed using a double vacuum chamber type apparatus. This will be described with reference to FIG. FIG. 5 shows an example of a double vacuum chamber type laminator. The laminator includes a lower chamber 54, an upper chamber 52, a silicone rubber sheet 53, and a heater 55. In the lower chamber 54 in the laminator, a laminate 59 of a substrate having unevenness and a photocurable transfer sheet or a laminate 59 of a substrate, a photocurable transfer sheet and a stamper is placed. Both the upper chamber 52 and the lower chamber 54 are evacuated (depressurized). The laminated body 59 is heated by the heater 55, and then the upper chamber 52 is returned to atmospheric pressure while the lower chamber 54 is exhausted, and the laminated body is pressure-bonded. Cool and take out the laminate and move to the next step. Thereby, defoaming is sufficiently performed at the time of exhaust, and the stamper or the substrate and the photocurable transfer sheet can be pressure-bonded without any bubbles.

The photocurable transfer sheet used in the present invention has a photocurable transfer layer made of a photocurable composition containing the above-mentioned specific organic thiourea compound and deformable by pressurization.
The photocurable composition of the present invention generally comprises a specific thiouracil derivative of the above formula (1) or (2), a polymer (preferably a polymer having a glass transition temperature of 80 ° C. or higher), a photopolymerizable functional group (generally It comprises a reactive diluent (monomer and oligomer) having a carbon-carbon double bond group (preferably a (meth) acryloyl group), a photopolymerization initiator, and optionally other additives.

  The characteristic requirement of the present invention is that the photocurable composition has the following formula (1) or (2):

[However, R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms , and at least one of R ¹ and R ² is a hydrogen atom,
R ³ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms ,
R ⁴ represents an alkylene group having 1 to 20 carbon atoms , or an alkylene group having 2 to 20 carbon atoms having an ether bond, ester bond, siloxane bond or phenylene group in the middle , and Z represents methacryloyloxy Represents a group, acryloyloxy group, 4-vinylbenzyloxy group, styryl group, allyloxy group or allyl group . ]
The thiouracil derivative represented by these is included.
Preferred examples of carbon atom number 1-12 alkyl groups, methylation, ethyl, n- propyl, isopropyl, n-butyl, i- butyl, t- butyl, n- pentyl, isopentyl, neopentyl, n- Hexyl can be mentioned. Further, an alkyl group having 1 to 4 carbon atoms is preferred, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, i-butyl and t-butyl.

Preferred examples of R ⁴ include

を挙げることができる。

Can be mentioned.

Among the above, R ⁴ is preferably (a), (b), (e), (f), or (j), particularly preferably (a).

Z is especially, methacryloyloxy group, acryloyloxy group is preferred in view of such polymerizable and easy handling.

  The thiouracil derivative is represented by the following formula (3) or (4):

[However, R ⁵ and R ⁶ each represent a hydrogen atom or an alkyl group, and at least one of R ⁵ and R ⁶ is a hydrogen atom,
R ⁷ represents a hydrogen atom, an alkyl group or a phenyl group,
R ⁸ is a divalent saturated hydrocarbon group having 2 to 12 carbon atoms, —CH ₂ —C ₆ H ₄ —CH ₂ — or — (CH ₂ ) _O —Si (CH ₃ ) ₂ OSi (CH ₃ ) ₂ — (CH ₂ ) _P — (wherein o and p are each independently an integer of 1 to 5),
Y represents —COO—, —CH ₂ O— or —C ₆ H ₄ —CH ₂ O—, and R ⁹ represents a hydrogen atom or a methyl group. ]
It is preferable that it is a compound represented by these.

In the above formula (3) or (4),
R ⁵ , R ⁶ and R ⁷ are preferably hydrogen atoms,
R ⁸ is preferably a divalent saturated hydrocarbon group having 2 to 12 carbon atoms, and R ⁹ is preferably a hydrogen atom or a methyl group.

  Preferred examples of the thiouracil derivative represented by the above formula (3) or (4) include the following:

The manufacturing method of the thiouracil derivative shown by the said General formula (1)-(4) can be manufactured by a well-known method. For example, it can be performed roughly as follows.
A carboureothiouracil derivative is obtained by condensation reaction of a thiourea derivative and a malonic acid derivative, and then a carboxythiouracil derivative is obtained by a deesterification reaction, followed by reaction with an alcohol having a polymerizable unsaturated bond. Thus, a thiouracil derivative having a polymerizable unsaturated bond represented by the general formula (3) can be obtained. Details of the production method are described in paragraph Nos. 0028 to 0149 in the specification of Japanese Patent No. 3296476.

  The content of the thiouracil derivative of the above formula (1) or (2) is generally 0.1 to 20% by mass, 0.2 to 10% by mass, particularly 0.5 to 8% by mass with respect to the polymer (solid content). % Is preferred.

  By using the thiouracil derivative of (1) or (2) of the present invention, the transfer layer of the photocurable transfer sheet photocured in a state where the stamper is in close contact with the silver alloy (AgX (X: preferably Cu · Excellent adhesion to reflective layers such as Pd or Cu · Nd)), and good release from the stamper, so part of the cured transfer layer peels off the reflective layer and adheres to the stamper There is little to do. The excellent adhesion of the cured transfer layer to the reflective layer is that the specific triazine derivative of the present invention has a higher affinity for the silver alloy of the reflective layer than Ni as the stamper material. it is conceivable that. That is, the triazine derivative of the present invention is incorporated into a cured product formed from the photocurable composition, and the S group and / or amino group of the thiouracil derivative of (1) or (2) is directed to the reflective layer side. It is presumed that the state is well maintained.

  Therefore, the optical information recording medium of the present invention accurately remains on the reflective layer in a state where the stamper shape (uneven portion) on the surface of the cured transfer layer, which is the recording surface, has been transferred. Can be carried out without error, and the adhesiveness between the surface of the cured transfer layer and the reflective layer is greatly improved, so that it can be said to be an optical disc having excellent durability. Therefore, such an optical disc can be used stably over a long period of time.

As the reactive diluent having a photopolymerizable functional group, which is a general constituent requirement of the photocurable composition of the present invention, for example, as a (meth) acrylic monomer, 2-hydroxyethyl (meth) acrylate, 2 -Hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylhexyl polyethoxy (meth) acrylate, benzyl (Meth) acrylate, isobornyl (meth) acrylate, phenyloxyethyl (meth) acrylate, tricyclodecane mono (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acrylic Yl morpholine, N- vinylcaprolactam, o- phenylphenyl oxyethyl (meth) acrylate,
Neopentyl glycol di (meth) acrylate, neopentyl glycol dipropoxy di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, 1,6-hexanediol di (Meth) acrylate, nonanediol di (meth) acrylate,
Glycerin diacrylate, glycerin acrylate methacrylate, glycerin dimethacrylate, trimethylolpropane diacrylate, trimethylolpropane acrylate methacrylate, trimethylolpropane dimethacrylate,
(Meth) such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tris [(meth) acryloxyethyl] isocyanurate, ditrimethylolpropane tetra (meth) acrylate Acrylate monomers;
Polyol compounds (for example, ethylene glycol, propylene glycol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butyl-1, Polyols such as 3-propanediol, trimethylolpropane, diethylene glycol, dipropylene glycol, polypropylene glycol, 1,4-dimethylolcyclohexane, bisphenol A polyethoxydiol, polytetramethylene glycol, the polyols and succinic acid, maleic acid Polyester polyols which are reaction products of polybasic acids such as itaconic acid, adipic acid, hydrogenated dimer acid, phthalic acid, isophthalic acid, terephthalic acid, etc., or their acid anhydrides, and the above-mentioned polyols and ε-capro Polycaprolactone polyols which are reaction products with kuton, reaction products of the above-mentioned polyols with ε-caprolactone of polybasic acids or anhydrides thereof, polycarbonate polyols, polymer polyols, etc.) and organic polyisocyanates ( For example, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane-4,4′-diisocyanate, dicyclopentanyl diisocyanate, hexamethylene diisocyanate, 2,4,4′-trimethylhexamethylene diisocyanate, 2,2 ′, 4 -Trimethylhexamethylene diisocyanate and the like) and hydroxyl group-containing (meth) acrylate (for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxy Roxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, cyclohexane-1,4-dimethylol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, glycerin di (meth) acrylate, etc.) Polyurethane (meth) acrylate, which is a reaction product of
Examples thereof include (meth) acrylate oligomers such as bisphenol type epoxy (meth) acrylate, which is a reaction product of bisphenol type epoxy resin such as bisphenol A type epoxy resin and bisphenol F type epoxy resin, and (meth) acrylic acid. These compounds having a photopolymerizable functional group can be used alone or in combination of two or more.

  In the present invention, it is preferable to use a compound having a hydroxyl group and an acryloyl group and / or a methacryloyl group as the reactive diluent. Such compounds are generally represented by the following formula (II):

[However, R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and may be the same or different from each other;
R ² represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a hydroxyalkyl group having 1 to 5 carbon atoms,
R ³ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and may be the same or different from each other;
R ⁴ represents an alkylene group having 1 to 5 carbon atoms,
X and Y each independently represents an acryloyloxy group or a methacryloyloxy group, and n represents 0 or 1. ]
It is represented by

In the general formula (II), R ¹ represents a hydrogen atom, R ² represents a hydrogen atom, methyl, ethyl or hydroxymethyl group, R ³ represents a hydrogen atom, R ⁴ represents a methylene group, It is preferable that X and Y each independently represent an acryloyloxy group or a methacryloyloxy group, and n represents 0 or 1. In particular, in the general formula (II), R ¹ represents a hydrogen atom, R ² represents hydrogen, R ⁴ represents hydrogen, and X and Y are each independently an acryloyloxy group or a methacryloyloxy group. And n preferably represents 0.

  Preferred examples of the compound of the general formula (II) include glycerin diacrylate (particularly 1,3-diacryloyl-propanetriol), glycerin acrylate methacrylate (particularly 1-acryloyl-3-methacryloyl-propanetriol (trade name G- 201P; manufactured by Kyoeisha Chemical Co., Ltd.)), glycerol dimethacrylate (particularly 1,3-dimethacryloyl-propanetriol (trade name G-101P; manufactured by Kyoeisha Chemical Co., Ltd.)), trimethylolpropane diacrylate, trimethylol. Examples thereof include propane acrylate methacrylate and trimethylol propane dimethacrylate, and glycerol acrylate methacrylate and glycerol dimethacrylate are particularly preferable. In this invention, what has both acrylate and a methacrylate in a polyhydric alcohol is preferable.

  Such a specific compound is generally contained in a proportion of 5 to 70% by mass, preferably 5 to 50% by mass, particularly preferably 5 to 30% by mass, based on the reactive diluent. This makes it easy to obtain the above good adhesiveness and stamper peelability.

  Examples of the polymer (preferably having a glass transition temperature of 80 ° C. or higher) include acrylic resins, polyvinyl acetate, vinyl acetate / (meth) acrylate copolymers, ethylene / vinyl acetate copolymers, polystyrene and copolymers thereof, poly Vinyl chloride and its copolymer, butadiene / acrylonitrile copolymer, acrylonitrile / butadiene / styrene copolymer, methacrylate / acrylonitrile / butadiene / styrene copolymer, 2-chlorobutadiene-1,3-polymer, chlorinated rubber, Styrene / butadiene / styrene copolymer, styrene / isoprene / styrene block copolymer, epoxy resin, polyamide, polyester, polyurethane, cellulose ester, cellulose ether, polycarbonate, polyvinyl acetal, etc. Can.

  In the present invention, an acrylic resin is preferable from the viewpoint of good transferability and excellent curability. As described above, the acrylic resin is particularly preferably an acrylic resin having a photopolymerizable functional group or an acrylic resin having a hydroxyl group. In addition, when the acrylic resin contains at least 50% by mass (especially 60 to 90% by mass) of methyl methacrylate repeating units, it is easy to obtain an acrylic resin having a Tg of 80 ° C. or more, and good transferability and high-speed curability are also obtained. It is easy and preferable.

  The acrylic resin having a photopolymerizable functional group is generally an acrylic resin having a photopolymerizable functional group, wherein at least methyl methacrylate and an alkyl (meth) acrylate having an alcohol residue of 2 to 10 carbon atoms. A copolymer of one kind and glycidyl (meth) acrylate, in which a carboxylic acid having a photopolymerizable functional group is reacted with the glycidyl group, or methyl methacrylate and an alcohol residue having 2 to 10 carbon atoms. It is a copolymer of at least one alkyl (meth) acrylic acid ester and a carboxylic acid having a photopolymerizable functional group, and the carboxylic acid group is reacted with glycidyl (meth) acrylate. Appropriate combination with the reactive diluent makes it easy to achieve both good transferability and excellent curability.

  Alkyl (meth) acrylic acid ester having 2 to 10 carbon atoms (especially 3 to 5 carbon atoms) as an alcohol residue includes ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, Examples thereof include n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like. n-butyl (meth) acrylate, isobutyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are preferred. Further, such a (meth) acrylic acid ester is preferably contained in the polymer as a repeating unit in general in an amount of 5 to 30% by mass, particularly 10 to 30% by mass. The glycidyl (meth) acrylate or carboxylic acid having a photopolymerizable functional group is preferably contained in the polymer in an amount of generally 5 to 25% by mass, particularly 5 to 20% by mass as the repeating unit. The glycidyl group or carboxylic acid group of the obtained copolymer is reacted with a carboxylic acid or glycidyl (meth) acrylate having a photopolymerizable functional group, respectively.

  The hydroxyl group-containing acrylic resin generally includes methyl methacrylate, at least one kind of alkyl (meth) acrylic acid ester having 2 to 10 (particularly 3 to 5) carbon atoms, and alcohol residues. Is a copolymer with at least one alkyl (meth) acrylic acid ester having 2 to 4 carbon atoms having a hydroxyl group. Methyl methacrylate is preferably contained as a repeating unit in an amount of 50% by mass or more (particularly 60 to 90% by mass) in the polymer. Appropriate combination with the reactive diluent makes it easy to achieve both good transferability and excellent curability. Alkyl (meth) acrylic acid ester having 2 to 10 carbon atoms (especially 3 to 5 carbon atoms) as an alcohol residue includes ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, Examples thereof include n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like. n-butyl (meth) acrylate, isobutyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are preferred. Further, such a (meth) acrylic acid ester is preferably contained in the polymer as a repeating unit in general in an amount of 5 to 30% by mass, particularly 10 to 30% by mass. Examples of the alkyl (meth) acrylic acid ester having 2 to 4 carbon atoms in which the alcohol residue has a hydroxyl group include 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate. In general, it is preferably contained in an amount of 5 to 25% by mass, particularly 5 to 20% by mass.

  The acrylic resin having the photopolymerizable functional group can be produced, for example, as follows.

  One or a plurality of (meth) acrylic monomers (preferably methyl methacrylate, at least one (meth) acrylic acid ester having an alcohol residue of 2 to 10 carbon atoms, and a glycidyl group). A solution polymerization method of a compound having 1 photopolymerizable functional group (preferably glycidyl (meth) acrylate) or a carboxylic acid having a photopolymerizable functional group in the presence of a radical polymerization initiator and an organic solvent. The glycidyl group-containing acrylic resin (a) or the carboxyl group-containing acrylic resin (b) which is a copolymer is obtained by reacting by a known method of 1. The blending ratio of monomers such as (meth) acrylic monomer is glycidyl group-containing. It is set as 10-45 mass% with respect to solid content conversion total amount of an acrylic resin (a) or a carboxyl group-containing acrylic resin (b). Door is preferable.

  Subsequently, a carboxylic acid having a photopolymerizable functional group is added to the obtained glycidyl group-containing acrylic resin (a), or one glycidyl group and a photopolymerizable functional group are added to the obtained carboxyl group-containing acrylic resin (b). An acrylic photocurable resin (A) or an acrylic photocurable resin (B) is obtained by adding one compound (preferably glycidyl methacrylate) and heating as necessary. This blending ratio is preferably blended so that the molar ratio of glycidyl group to carboxyl group is 1 / 0.9 to 1/1, and more preferably 1/1. If the glycidyl group is excessive, viscosity and gelation may occur in long-term stability, and if the carboxyl group is excessive, skin irritation increases and workability decreases. Further, in the case of 1/1, there is no residual glycidyl group, and the storage stability is remarkably improved. The reaction can be carried out by a known method in the presence of a basic catalyst, a phosphorus catalyst or the like.

  The (meth) acrylic monomer that can be used as a main component constituting the acrylic resin that can be used in the present invention, including the acrylic resin having the OH or photopolymerizable functional group, includes acrylic acid or methacrylic acid. Various esters can be mentioned. Examples of various esters of acrylic acid or methacrylic acid include methyl (meth) acrylate ((meth) acrylate means acrylate and methacrylate; the same applies hereinafter), ethyl (meth) acrylate, n-propyl (meth) acrylate, n- Alkyl (meta) such as butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, and tridecyl (meth) acrylate ) Acrylate, ethoxyethyl (meth) acrylate, alkoxyalkyl (meth) acrylate such as butoxyethyl (meth) acrylate, 2-methoxyethoxyethyl (meth) acrylate, 2-ethoxyethoxyethyl Alkoxyalkoxyalkyl (meth) acrylates such as meth) acrylate, methoxydiethylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, butoxytriethylene glycol (meth) acrylate, methoxydipropylene glycol ( Dialkylamino such as alkoxy (poly) alkylene glycol (meth) acrylate such as (meth) acrylate, pyrenoxide adduct (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate An alkyl (meth) acrylate etc. can be mentioned. Further, an aromatic compound containing an unsaturated group (eg, styrene) may be used.

  In the present invention, as described above, as the main component of the acrylic monomer, at least one of methyl methacrylate and an alkyl (meth) acrylate having 2 to 10 carbon atoms as an alcohol residue is used. Is preferred.

  The polymer of the present invention (preferably having a glass transition temperature of 80 ° C. or higher) preferably has a number average molecular weight of 100,000 or more, particularly 100,000 to 300,000, and a weight average molecular weight of 100,000 or more, particularly 100,000 to 300,000.

  Furthermore, in the present invention, a polymer having both a functional group having an active hydrogen such as a hydroxyl group and a photopolymerizable functional group can also be used as the polymer (preferably having a glass transition temperature of 80 ° C. or higher). As such a reactive polymer, for example, a homopolymer or a copolymer (that is, an acrylic resin) mainly obtained from the acrylic monomer, and a photopolymerizable functional group and active hydrogen are present in the main chain or side chain. It has a functional group. Therefore, such a reactive polymer includes, for example, methyl methacrylate, the one or more (meth) acrylates, and a (meth) acrylate having a functional group such as a hydroxyl group (eg, 2-hydroxyethyl (meth) acrylate). ) And the resulting polymer reacts with a functional group of the polymer and a compound having a photopolymerizable group, such as isocyanatoalkyl (meth) acrylate. In that case, the polymer which has a hydroxyl group and a photopolymerizable functional group as a functional group which has active hydrogen is obtained by adjusting and using the amount of isocyanatoalkyl (meth) acrylate so that a hydroxyl group may remain.

  Alternatively, in the above, a photopolymerizable functional group having an amino group as a functional group having active hydrogen by using a (meth) acrylate having an amino group instead of a hydroxyl group (eg, 2-aminoethyl (meth) acrylate) A containing polymer can be obtained. Similarly, a photopolymerizable functional group-containing polymer having a carboxyl group or the like as a functional group having active hydrogen can also be obtained.

  In the present invention, an acrylic resin having the photopolymerizable functional group via a urethane bond is also preferable.

  The polymer having a photopolymerizable functional group and a functional group having active hydrogen generally contains 1 to 50 mol%, particularly 5 to 30 mol% of the photopolymerizable functional group. As this photopolymerizable functional group, an acryloyl group, a methacryloyl group, and a vinyl group are preferable, and an acryloyl group and a methacryloyl group are particularly preferable.

  Diisocyanates that can be added to the photocurable composition of the present invention include tolylene diisocyanate (TDI), isophorone diisocyanate, xylylene diisocyanate, diphenylmethane-4,4-diisocyanate, dicyclopentanyl diisocyanate, hexamethylene diisocyanate, 2 4,4'-trimethylhexamethylene diisocyanate and 2,2 ', 4-trimethylhexamethylene diisocyanate. Polyisocyanate cyanates such as trifunctional or higher functional isocyanate compounds such as a TDI adduct of trimethylolpropane can also be used. Of these, a hexamethylene diisocyanate adduct of trimethylolpropane is preferred.

It is preferable that the diisocyanate of this invention is contained in 0.2-4 mass% in the photocurable composition (nonvolatile content), especially 0.2-2 mass%. Appropriate crosslinking is provided to prevent the transfer layer from seeping out, and good transferability of the unevenness of the substrate and stamper is also maintained. The reaction between the compound and the polymer proceeds gradually after the transfer layer is formed, and reacts considerably at room temperature (generally 25 ° C.) at 24 hours. It is considered that the reaction proceeds after the coating solution for forming the transfer layer is prepared and before the coating solution is applied. After forming the transfer layer, it is preferable to cure to a certain extent before winding it in the roll state. If necessary, the reaction is promoted by heating during the formation of the transfer layer or before winding in the roll state. You may let them.
As described above, the photocurable composition of the present invention generally contains the specific thiouracil derivative of the present invention, a polymer having a glass transition temperature of 80 ° C. or higher, and a photopolymerizable functional group (preferably a (meth) acryloyl group). It comprises a reactive diluent (monomers and oligomers), a photopolymerizable initiator, and optionally other additives. The mass ratio of polymer to reactive diluent is preferably in the range of 20:80 to 80:20, particularly 30:70 to 70:30.

The storage elastic modulus at a frequency of 1 Hz of the photocurable transfer layer of the present invention is preferably 1 × 10 ⁷ Pa or less at 25 ° C., and particularly preferably in the range of 1 × 10 ^{4 to} 6 × 10 ⁵ Pa. . Moreover, it is preferable that it is 8 * 10 < ⁴ > Pa or less in 80 degreeC, and it is especially preferable that it is the range of 1 * 10 < ⁴ > -5 * 10 < ⁵ > Pa. This enables accurate and quick transfer. Furthermore, the photocurable transfer layer of the present invention preferably has a glass transition temperature of 20 ° C. or lower. Thereby, when the obtained photocurable transfer layer is pressure-bonded to the uneven surface of the stamper, it can have flexibility that can closely follow the uneven surface even at room temperature. In particular, when the glass transition temperature is in the range of 15 ° C. to −50 ° C., particularly 15 ° C. to −10 ° C., the following property is obtained. If the glass transition temperature is too high, a high pressure and a high pressure are required at the time of attachment, leading to a decrease in workability. If it is too low, a sufficient altitude after curing cannot be obtained.

The photocurable transfer layer made of the photocurable composition is preferably designed so that the glass transition temperature after irradiation with 300 mJ / cm ² of ultraviolet light is 65 ° C. or higher. By irradiating with ultraviolet rays for a short time, it is easy to prevent the occurrence of sagging such as a pit shape that is likely to occur due to residual stress during transfer, and the transferred pit shape can be retained. The photocurable transfer layer comprising the photocurable composition of the present invention can be advantageously obtained mainly by using the above preferred polymer and the following reactive diluent.

  As the photopolymerization initiator, any known photopolymerization initiator can be used, but one having good storage stability after blending is desirable. Examples of such photopolymerization initiators include benzoin series such as acetophenone series and benzyldimethyl ketal, thiophenone series such as benzophenone series, isopropylthioxanthone, and 2-4-diethylthioxanthone, and other special types include methylphenylglycol. Oxylate can be used. Particularly preferably, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1, Examples include benzophenone. These photopolymerization initiators may contain one or two or more kinds of known and commonly used photopolymerization accelerators such as benzoic acid-based or tertiary amine-based compounds such as 4-dimethylaminobenzoic acid as required. Can be mixed and used. Moreover, it can be used by 1 type, or 2 or more types of mixture of only a photoinitiator. In general, the photocurable initiator (all components) preferably contains a photopolymerization initiator in an amount of 0.1 to 20% by mass, particularly 1 to 10% by mass.

  Among the photopolymerization initiators, examples of the acetophenone-based polymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, and 2-hydroxy-2. -Methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methyl Propan-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2 As benzophenone polymerization initiators such as morpholinopropane-1, Benzophenone, benzoyl benzoate, methyl benzoyl benzoate, 4-phenyl benzophenone, hydroxybenzophenone, 4-Benzzoiru 4'-methyl diphenyl sulfide, etc. 3,3'-dimethyl-4-methoxybenzophenone may be used.

  As the acetophenone-based polymerization initiator, in particular, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2 -Morpholinopropane-1 is preferred. As the benzophenone polymerization initiator, benzophenone, benzoylbenzoic acid, and methyl benzoylbenzoate are preferable. Tertiary amine photopolymerization accelerators include triethanolamine, methyldiethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, ethyl 2-dimethylaminobenzoate. , Ethyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate and the like can be used. Particularly preferably, as the photopolymerization accelerator, ethyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, etc. Is mentioned.

  In the present invention, in addition to the reactive diluent having a photopolymerizable functional group and the photopolymerization initiator, it is preferable to add the following thermoplastic resin and other additives as required.

  As another additive, a silane coupling agent (adhesion promoter) can be added. As this silane coupling agent, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy Propyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-chloropropylmethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β There are (aminoethyl) -γ-aminopropyltrimethoxysilane and the like, and one of these can be used alone or two or more of them can be used in combination. As for the addition amount of these silane coupling agents, 0.01-5 mass parts is sufficient normally with respect to 100 mass parts of said polymers (solid content).

  Similarly, an epoxy group-containing compound can be added for the purpose of improving adhesiveness. Examples of the epoxy group-containing compound include triglycidyl tris (2-hydroxyethyl) isocyanurate; neopentyl glycol diglycidyl ether; 1,6-hexanediol diglycidyl ether; acrylic glycidyl ether; 2-ethylhexyl glycidyl ether; Examples thereof include phenol glycidyl ether; pt-butylphenyl glycidyl ether; adipic acid diglycidyl ester; o-phthalic acid diglycidyl ester; glycidyl methacrylate; Further, the same effect can be obtained by adding an oligomer containing an epoxy group having a molecular weight of several hundred to several thousand or a polymer having a weight average molecular weight of several thousand to several hundred thousand. The addition amount of these epoxy group-containing compounds is sufficient to be 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer (solid content), and at least one of the epoxy group-containing compounds is added alone or in combination. Can do.

  As another additive, a hydrocarbon resin can be added for the purpose of improving workability such as workability and bonding. In this case, the added hydrocarbon resin may be either a natural resin type or a synthetic resin type. In natural resin systems, rosin, rosin derivatives, and terpene resins are preferably used. For rosin, gum-based resins, tall oil-based resins, and wood-based resins can be used. As the rosin derivative, rosin obtained by hydrogenation, heterogeneity, polymerization, esterification, or metal chloride can be used. As the terpene resin, a terpene phenol resin can be used in addition to a terpene resin such as α-pinene and β-pinene. In addition, dammar, corbal and shellac may be used as other natural resins. On the other hand, in the synthetic resin system, petroleum resin, phenol resin, and xylene resin are preferably used. As the petroleum resin, aliphatic petroleum resin, aromatic petroleum resin, alicyclic petroleum resin, copolymer petroleum resin, hydrogenated petroleum resin, pure monomer petroleum resin, and coumarone indene resin can be used. As the phenol resin, an alkyl phenol resin or a modified phenol resin can be used. As the xylene-based resin, a xylene resin or a modified xylene resin can be used.

  Although the addition amount of polymers, such as the said hydrocarbon resin, is selected suitably, 1-20 mass parts is preferable with respect to 100 mass parts of said polymers (solid content), More preferably, it is 5-15 mass parts.

  In addition to the above additives, the photocurable composition of the present invention may contain a small amount of an ultraviolet absorber, an antioxidant, a dye, a processing aid and the like. In some cases, additives such as silica gel, calcium carbonate, and fine particles of silicone copolymer may be included in a small amount.

  The photocurable transfer sheet comprising the photocurable composition of the present invention includes a thiouracil derivative of the present invention, a polymer (preferably Tg of 80 ° C. or higher), a reactive diluent (monomer and oligomer) having a photopolymerizable functional group, desired After mixing with diisocyanate cyanate and other additives as desired, kneading with an extruder, roll, etc., and forming into a predetermined shape by a film forming method such as calendar, roll, T-die extrusion, inflation, etc. Can be used. When using a support, it is necessary to form a film on the support. More preferably, the photocurable adhesive film-forming method of the present invention is obtained by uniformly mixing and dissolving each constituent component in a good solvent, and then applying this solution to a separator precisely coated with silicone or fluororesin. , A gravure roll method, a Myer bar method, a lip die coating method or the like, and a method of forming a film by drying a solvent.

  The thickness of the photocurable transfer sheet is preferably 1 to 1200 μm, particularly preferably 5 to 500 μm. Particularly preferred is 5 to 300 μm (preferably 150 μm or less). If it is thinner than 1 μm, the sealing performance is poor, and the unevenness of the transparent resin substrate may not be filled. On the other hand, if the thickness is larger than 1000 μm, the thickness of the recording medium increases, which may cause problems in the storage and assembly of the recording medium, and may also affect the light transmission.

  It is preferable that release sheets are attached to both sides of the photocurable transfer sheet.

  As a material for the release sheet, a transparent organic resin having a glass transition temperature of 50 ° C. or higher is preferable. As such a material, polyester resins such as polyethylene terephthalate, polycyclohexylene terephthalate, polyethylene naphthalate, nylon 46, modified In addition to polyamide resins such as nylon 6T, nylon MXD6, polyphthalamide, ketone resins such as polyphenylene sulfide and polythioether sulfone, and sulfone resins such as polysulfone and polyether sulfone, polyether nitrile, polyarylate, Use a transparent resin substrate mainly composed of an organic resin such as polyetherimide, polyamideimide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polystyrene, polyvinyl chloride, etc. Can. Of these, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, and polyethylene terephthalate can be suitably used. The thickness is preferably 10 to 200 μm, particularly preferably 30 to 100 μm.

  As a material for the substrate 21 having irregularities on the surface, a transparent organic resin having a glass transition temperature of 50 ° C. or higher is preferable. Examples of such a support include polyethylene terephthalate, polycyclohexylene terephthalate, and polyethylene naphthalate. In addition to polyester resins, nylon 46, modified nylon 6T, nylon MXD6, polyamide resins such as polyphthalamide, ketone resins such as polyphenylene sulfide and polythioether sulfone, and sulfone resins such as polysulfone and polyether sulfone Organic resin such as polyether nitrile, polyarylate, polyether imide, polyamide imide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polystyrene, polyvinyl chloride It can be used transparent resin substrate that. Among these, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, and polyethylene terephthalate are excellent in terms of transferability and birefringence, and can be suitably used. The thickness is preferably 200 to 2000 μm, particularly preferably 500 to 1500 μm.

  The organic polymer film material 26 is preferably a transparent organic resin having a glass transition temperature of 50 ° C. or higher. Examples of such a support include polyester resins such as polyethylene terephthalate, polycyclohexylene terephthalate, and polyethylene naphthalate, and nylon. 46, modified nylon 6T, nylon MXD6, polyamide resins such as polyphthalamide, ketone resins such as polyphenylene sulfide and polythioether sulfone, polysulfone, sulfone resins such as polyether sulfone, polyether nitrile, Transparent tree mainly composed of organic resins such as polyarylate, polyetherimide, polyamideimide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polystyrene, polyvinyl chloride Substrate can be used. Among these, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, and polyethylene terephthalate are excellent in terms of transferability and birefringence, and can be suitably used. The thickness is preferably 10 to 200 μm, particularly preferably 50 to 100 μm.

  In the photocurable transfer sheet thus obtained in the present invention, it is preferable that the light transmittance in the wavelength region of 380 to 420 nm of the photocurable transfer layer is 70% or more.

  The photocurable transfer sheet has a light transmittance of 70% or more in a wavelength region of 380 to 420 nm (preferably 380 to 800 nm), in order to prevent a decrease in intensity of a read signal by a laser. Furthermore, the light transmittance in the wavelength region of 380 to 420 nm is preferably 80% or more.

  Since the photocurable transfer sheet of the present invention can be provided in the form of a film whose film thickness accuracy is precisely controlled, it is possible to easily and accurately bond the substrate and the stamper. In addition, this bonding can be carried out at 20 to 100 ° C. by a simple method such as a pressure roll or a simple press, and then cured by light at room temperature for 1 to several tens of seconds. Since it is difficult for displacement and peeling to occur in the laminate, it has a feature that it can be handled freely until photocuring.

When the photocurable transfer sheet of the present invention is cured, many light sources that emit light in the ultraviolet to visible region can be used as the light source, for example, ultrahigh pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, Mercury halogen. A lamp, a carbon arc lamp, an incandescent lamp, a laser beam, etc. are mentioned. The irradiation time is not generally determined depending on the type of the lamp and the intensity of the light source, but is about 0.1 to several tens of seconds, preferably 0.5 to several seconds. The ultraviolet irradiation amount is preferably 300 mJ / cm ² or more.

  In order to accelerate curing, the laminate may be preheated to 30 to 80 ° C. and irradiated with ultraviolet rays.

  The obtained reflective layer on the uneven surface of the substrate of the present invention is formed by metal deposition (for example, sputtering, vacuum deposition, ion plating, etc.) of the reflective layer on the substrate. Examples of the metal include aluminum, gold, silver, and alloys thereof. A silver alloy is preferable, and AgX (X is preferably Cu · Pd or Cu · Nd) is particularly preferable. In general, the translucent reflective layer on the substrate is formed using silver or the like as a metal. That is, on the cured layer of the transfer layer, it is necessary to provide a reflective layer having a higher reflectance than the reflective layer, and the components, layer thickness, and the like are changed. For example, since the reflectance can be changed by changing the layer thickness of the silver alloy reflective layer, a plurality of reflective layers (from the low reflective layer to the high reflective layer) can be changed by changing the thickness of the silver alloy reflective layer. Can be provided.

When an organic polymer film is pasted on the reflective layer of the cured sheet, an adhesive is applied on one side, and the other is stacked thereon and cured. When the adhesive is a UV curable resin, it is obtained by UV irradiation, and when it is a hot melt adhesive, it is obtained by applying and cooling under heating.
The production of the optical information recording medium of the present invention is usually processed in a disc shape as described above, but it may be made continuously in a sheet shape and finally in a disc shape.

  The following examples further illustrate the present invention.

[Example 1]
<Preparation of photocurable transfer sheet>
(Preparation of polymer 1 having a hydroxyl group)
Polymer blend 1
Methyl methacrylate 74.6 parts by mass n-butyl methacrylate 13.2 parts by mass 2-hydroxyethyl methacrylate 12.1 parts by mass AIBN 1.2 parts by mass Toluene 70 parts by mass Ethyl acetate 30 parts by mass While stirring, the mixture was heated to 70 ° C. to initiate polymerization, and stirred at this temperature for 8 hours to obtain Polymer 1 (acrylic resin) having a hydroxyl group having a hydroxyl group in the side chain. The solid content was adjusted to 36% by mass (polymer solution 1).

  The obtained polymer 1 had a Tg of 90 ° C. and a weight average molecular weight of 110,000.

Composition formulation 1
100 parts by mass of polymer solution 1 having a hydroxyl group (solid content)
Hexanediol diacrylate 100 parts by mass (KS-HDDA; manufactured by Kyoeisha Chemical Co., Ltd.)
Trimethylolpropane triacrylate (TMP-A; manufactured by Kyoeisha Chemical Co., Ltd.) 20 parts by mass ^* Thiouracil compound (1) having the following structure 5 parts by mass Diisocyanate (BXX5627, manufactured by Toyo Ink Co., Ltd.) 1 part by mass Irgacure 184
(Ciba Specialty Chemicals Co., Ltd.) 1 part by mass
^* Thiouracil compound (1)

  The mixture having the above composition was uniformly dissolved and kneaded, and applied onto the entire surface of a release sheet (width 140 mm, length 300 m, thickness 75 μm; trade name No. 23, manufactured by Fujimori Kogyo Co., Ltd.), and a dry thickness of 25 μm. A photocurable transfer layer was formed, and the same release sheet as above was attached to the opposite side of the sheet and rolled up into a roll to obtain a full edge type roll (diameter 260 mm) of the photocurable transfer sheet.

  The storage elastic modulus of the photocurable transfer layer of the obtained photocurable transfer sheet was as shown in Table 1, and Tg was −20 ° C.

[Example 2]
In Example 1, the following thiouracil compound (2) instead of the thiouracil compound (1) in composition 1 was:

を使用した以外は、同様にして光硬化性転写シートを得た。

A photocurable transfer sheet was obtained in the same manner except that was used.

[Example 3]
In Example 1, the following thiouracil compound (3) instead of the thiouracil compound (1) in composition 1 was:

を使用した以外は、同様にして光硬化性転写シートを得た。

A photocurable transfer sheet was obtained in the same manner except that was used.

[Example 4]
A photocurable transfer sheet was obtained in the same manner as in Example 1 except that the composition 1 was used as the composition 2 below.
Composition formulation 2
100 parts by mass of polymer solution 1 having a hydroxyl group (solid content)
Hexanediol diacrylate (KS-HDDA) 100 parts by mass Trimethylolpropane triacrylate (TMP-A; manufactured by Kyoeisha Chemical Co., Ltd.) 20 parts by mass 2-hydroxy-3-acryloyloxypropyl methacrylate (G-201P; Kyoeisha Chemical) 20 parts by mass The thiouracil compound (1) 5 parts by mass Diisocyanate (BXX5627, manufactured by Toyo Ink Co., Ltd.) 1 part by mass Irgacure 651
(Ciba Specialty Chemicals Co., Ltd.) 1 part by mass Hydroquinone monomethyl ether (MEHQ) 0.05 part by mass The storage modulus of the photocurable transfer layer of the obtained photocurable transfer sheet is as shown in Table 1. Yes, Tg was −20 ° C.

[Example 5]
In Example 4, the photocurable transfer sheet was obtained similarly except having used the said thiouracil compound (2) instead of the thiouracil compound (1) of the composition mixing | blending 2.

[Example 6]
In Example 4, the photocurable transfer sheet was obtained similarly except having used the said thiouracil compound (3) instead of the thiouracil compound (1) of the composition mixing | blending 1. FIG.

[Comparative Example 1]
In Example 1, a photocurable transfer sheet was obtained in the same manner except that the thiouracil compound (1) was not used for the preparation of the composition.

(1) Evaluation of photocurable transfer sheet (1-1) Measurement of glass transition temperature (Tg) The release sheets on both sides were removed from the obtained photocurable transfer sheet, and the length was 20 mm and the width was 4 mm (thickness 25 μm). ) To obtain a sample.

Using a TMA (Thermal Mechanical Analysis) apparatus SS6100 (manufactured by SII Nanotechnology Co., Ltd.), Tg of the sample was sample temperature: 30 to 120 ° C., temperature rising rate: 5 ° C./min, tensile tension: 4.9 × The measurement was performed at 10 ⁵ Pa.

  When the test was performed under the above conditions, the graph shown in FIG. 6 was obtained, and the intersection of the tangent line of the stable region and the tangent line from the maximum slope of the stretch region was defined as the glass transition temperature.

(1-2) Measurement of storage elastic modulus of transfer sheet The storage elastic modulus of the transfer layer of the obtained transfer sheet was measured using Rheo Stress RS300 (manufactured by HAAKE) as a viscoelasticity measuring device. At that time, using a parallel plate jig of φ = 8 mm, measurement was performed at a measurement thickness of 400 μm (used by laminating a transfer layer), measurement temperatures of 25 ° C. and 80 ° C., and a frequency of 1 Hz.

(2) Production and Evaluation of Optical Information Recording Medium (2-1) Production of Laminate (Optical Information Recording Medium) of Substrate, Reflective Layer, and Cured Transfer Layer After punching the roll of the photocurable transfer sheet into a disk shape, Thickness provided on the uneven surface of a polycarbonate substrate (thickness: 1.1 mm) having a concavo-convex surface as a pit formed by injection molding the disk-shaped photocurable transfer sheet obtained by removing one release sheet Arranged on a semi-transmissive reflective layer of a 40 nm silver alloy (Ag.Cu.Nd (composition ratio 98.4: 0.7: 0.9 (mass))) so that the transfer sheet surface and the reflective layer are in contact with each other. The photocurable transfer sheet was pressed with a load of 2 kg using a silicone rubber roller to form a laminate (corresponding to (3) in FIG. 2).

  The other release sheet of the photocurable transfer sheet of the laminate was removed, and a nickel stamper having an uneven surface as a pit was temperature-controlled at 50 ° C. on the surface of the removed transfer sheet. Place the surface so that the surface of the sheet is in contact, press the stamper with a load of 2 kg using a roller made of silicone rubber, form a laminate, and transfer the uneven shape of the nickel stamper to the transfer sheet surface did.

Next, from the photo-curable transfer sheet side, using a metal halide lamp (600 mW / cm), the semi-transmissive reflective layer of the reflective layer (Ag / Cu / Nd) is used under the condition of an integrated light quantity of 300 mJ / cm ² . The transfer sheet was cured by UV irradiation (irradiation distance 20 cm, irradiation time 1.0 second).

  The stamper was peeled and removed from the laminate by pushing up the obtained laminate. Thereby, the laminated body of the hardening transfer layer in which the board | substrate, the reflection layer, and the uneven | corrugated shape were transcribe | transferred was obtained.

Subsequent steps such as formation of the reflective layer were omitted.
(2-2) Adhesiveness of cured transfer layer to reflective layer (Ag / Cu / Nd) in laminate (and releasability of stamper)
The laminate was manufactured five times (until the stamper was peeled off), and the degree of transfer of the obtained cured transfer layer to the stamper and the degree of peeling of the cured transfer layer were observed.

  After the stamper was removed, the case where all the cured transfer layer remained on the reflective layer was regarded as acceptable. The number of tests is shown in the denominator, and the number of passes is shown in the numerator (for example, 5/5 if all passes).

(2-3) Measurement of glass transition temperature (Tg) A sample obtained in the same manner as in (1-1) was irradiated with UV under the condition of an integrated light quantity of 300 mJ / cm ² , and as in (1-1). Tg was measured.

The integrated light quantity (300 mJ / cm ² ) was measured on the surface of the layer using UV Power Pack (UV-A band measurement) manufactured by Fusion UV Systems Japan Co., Ltd.

  The test results obtained are shown in Table 1.

  The photocurable transfer sheets obtained in Examples 1 to 6 are excellent in adhesion of the cured transfer layer to the reflective layer (the stamper was also excellent in peelability), whereas in Comparative Example 1, The adhesiveness was inferior. This is presumed to be because the specific thiouracil derivative of the present invention is not used.

It is sectional drawing which shows an example of embodiment of the photocurable transfer sheet according to this invention. It is sectional drawing which shows an example of the manufacturing method of the optical information recording medium according to this invention. It is sectional drawing which shows an example of the optical information recording medium according to this invention. It is sectional drawing which shows another example of the optical information recording medium according to this invention. It is this schematic for demonstrating the press method using the apparatus of a double vacuum chamber system. It is a graph used for determination of glass transition temperature (Tg). It is sectional drawing which shows the procedure of the manufacturing method of the optical information recording medium as described in Nikkei Electronics.

Explanation of symbols

11 Photocurable transfer layer 12a, 12b Release sheet 21 Substrate 23a, 23b, 23c, 23d Reflective layer 11a, 11b, 11c Cured photocurable transfer layer 24 Stamper 26 Organic polymer film (cover layer)

Claims (32)

A photocurable transfer sheet having a photocurable transfer layer made of a photocurable composition that can be deformed by pressurization,
The photocurable composition has the following formula (1) or (2):

[However, R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms , and at least one of R ¹ and R ² is a hydrogen atom,
R ³ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms ,
R ⁴ represents an alkylene group having 1 to 20 carbon atoms , or an alkylene group having 2 to 20 carbon atoms having an ether bond, ester bond, siloxane bond or phenylene group in the middle , and Z represents methacryloyloxy Represents a group, acryloyloxy group, 4-vinylbenzyloxy group, styryl group, allyloxy group or allyl group . ]
The photocurable transfer sheet characterized by including the thiouracil derivative represented by these.   The photocurable transfer sheet according to claim 1, wherein the photocurable composition contains a polymer and a reactive diluent having a photopolymerizable functional group. The thiouracil derivative is represented by the following formula (3) or (4):

[However, R ⁵ and R ⁶ each represent a hydrogen atom or an alkyl group, and at least one of R ⁵ and R ⁶ is a hydrogen atom,
R ⁷ represents a hydrogen atom, an alkyl group or a phenyl group,
R ⁸ is a divalent saturated hydrocarbon group having 2 to 12 carbon atoms, —CH ₂ —C ₆ H ₄ —CH ₂ — or — (CH ₂ ) _O —Si (CH ₃ ) ₂ OSi (CH ₃ ) ₂ — (CH ₂ ) _P — (wherein o and p are each independently an integer of 1 to 5),
Y represents —COO—, —CH ₂ O— or —C ₆ H ₄ —CH ₂ O—, and R ⁹ represents a hydrogen atom or a methyl group. ]
The photocurable transfer sheet of Claim 1 or 2 represented by these. R ⁵ , R ⁶ and R ⁷ represent a hydrogen atom,
R ⁸ represents a divalent saturated hydrocarbon group having 2 to 12 carbon atoms,
Y is, -COO -, - CH ₂ O- or -C ₆ H ₄ -CH ₂ O- and represent, and R ⁹ is, the photocurable transfer sheet according to claim 3 representing a hydrogen atom or a methyl group. The glass transition temperature of a polymer is 80 degreeC or more, The photocurable transfer sheet of any one of Claims 3-4 which cites Claim 2 and Claim 2 . The photocurable transfer sheet according to any one of claims 1 to 5 , wherein the photocurable transfer layer has a glass transition temperature of 65 ° C or higher after irradiation with 300 mJ / cm ² of ultraviolet rays. The photocurable transfer sheet according to any one of claims 1 to 6 , wherein the photocurable composition has a glass transition temperature of less than 20 ° C. The photocurable transfer sheet according to any one of claims 3 to 7 , wherein the polymer is an acrylic resin. The photocurable transfer sheet according to claim 8 , wherein the acrylic resin is an acrylic resin containing at least 50% by mass of repeating units of methyl methacrylate. The photocurable transfer sheet according to claim 8 or 9 , wherein the acrylic resin is an acrylic resin having a photopolymerizable functional group. The acrylic resin is a copolymer of methyl methacrylate, at least one kind of (meth) acrylic acid ester having an alcohol residue of 2 to 10 carbon atoms and glycidyl (meth) acrylate, and the glycidyl group The photocurable transfer sheet according to any one of claims 8 to 10 , which is obtained by reacting a carboxylic acid having a polymerizable functional group. The acrylic resin is a copolymer of methyl methacrylate, at least one kind of alkyl (meth) acrylic acid ester having an alcohol residue of 2 to 10 carbon atoms, and a carboxylic acid having a polymerizable functional group; and The photocurable transfer sheet according to any one of claims 8 to 10 , which is obtained by reacting the carboxylic acid group with glycidyl (meth) acrylate. The photocurable transfer sheet according to claim 8 or 9 , wherein the acrylic resin is an acrylic resin having a hydroxyl group. The acrylic resin is methyl methacrylate, at least one kind of alkyl (meth) acrylic acid ester having 2 to 10 carbon atoms in the alcohol residue, and 2 to 4 carbon atoms in which the alcohol residue has a hydroxyl group. The photocurable transfer sheet according to claim 8, 9 or 13 , which is a copolymer with at least one alkyl (meth) acrylate. The photocurable transfer sheet according to any one of claims 1 to 14 , wherein the photocurable composition further contains a diisocyanate. The photocurable transfer sheet according to any one of claims 2 and 3, wherein the polymer has a weight average molecular weight of 100,000 or more.   The photocurable transfer sheet according to any one of claims 1 to 16, wherein the photocurable composition contains 0.1 to 10% by mass of a photopolymerization initiator. The photocurable transfer sheet according to any one of claims 1 to 17 , wherein the light transmittance in a wavelength region of 380 to 420 nm is 70% or more. The photocurable transfer sheet according to any one of claims 1 to 18 , wherein the light transmittance in a wavelength region of 380 to 800 nm is 70% or more. The photocurable transfer sheet according to any one of claims 1 to 19 , wherein the photocurable transfer layer has a thickness of 5 to 300 µm. The photocurable transfer sheet according to any one of claims 1 to 20 , wherein a release sheet is provided on one or both surfaces of the photocurable transfer layer. The photocurable transfer sheet according to claim 21 , wherein the photocurable transfer sheet is long, and the photocurable transfer layer and the release sheet have substantially the same width. The following steps (2) to (4):
(2) When the photocurable transfer sheet according to claim 21 or 22 has a release sheet on both sides, the step of removing one of the release sheets;
(3) Photocuring of the photocurable transfer sheet on the reflective layer of the substrate having irregularities as recording pits and / or grooves on the surface and further provided with a reflective layer along the irregularities of the irregular surface. and mounting location so that the surface of sexual transfer layer in contact with the uneven surface of the reflective layer, those the presses laminate surface of the photocurable transfer sheet is in close contact along the uneven surface of the reflective layer A step of forming; and (4) a step of removing the other release sheet from the laminate.
The manufacturing method of the optical information recording medium characterized by the above-mentioned. Before the step (2),
(1) A step of punching out a photocurable transfer sheet into a disc shape; or (1) A step of punching out a photocurable transfer layer and one release sheet of a photocurable transfer sheet into a disc shape and leaving the other release sheet as it is. ;
24. The method for manufacturing an optical information recording medium according to claim 23 . After performing the step (4), (5) the uneven surface has a stamper having unevenness as recording pits and / or grooves on the surface of the photocurable transfer layer from which the release sheet of the laminate has been removed. step by mounting location so as to contact the surface of the transfer layer, these presses the surface of the photocurable transfer sheet to form a laminate in close contact along the uneven surface;
(6) A step of providing irregularities on the surface of the photocurable transfer layer by curing the photocurable transfer layer of the laminate having the stamper by ultraviolet irradiation and then removing the stamper;
The method for producing an optical information recording medium according to claim 23 or 24 . 26. The method of manufacturing an optical information recording medium according to claim 25 , wherein the ultraviolet irradiation of (6) is performed with an irradiation energy of at least 300 mJ / cm < ² >. 27. The method for producing an optical information recording medium according to claim 25 or 26 , wherein the glass transition temperature of the photocurable transfer layer obtained in (6) is 65 ° C. or higher. After performing the steps (5) to (6), (7) a step of providing a reflective layer on the uneven surface of the photocurable transfer layer;
The manufacturing method of the optical information recording medium of any one of Claims 25-27 containing this. An optical information recording medium obtained by the production method according to claim 23 . Has unevenness of the recording pits and / or grooves on the surface, the more the optical information recording substrate of the reflective layer having a reflective layer formed on the uneven surface, one of the claims 1 to 22 along the unevenness An optical information recording medium comprising a cured layer of a photocurable transfer layer of the photocurable transfer sheet according to claim 1. On the surface of the optical information recording substrate having irregularities as recording pits and / or grooves and further having a reflective layer formed on the irregular surface, irregularities as recording pits and / or grooves are formed on the surface. An intermediate resin layer having a reflective layer formed on the uneven surface, the surface of the intermediate resin layer having no unevenness facing the reflective layer on the substrate surface, An optical information recording medium provided along the unevenness,
An optical information recording medium, wherein the intermediate resin layer is a cured layer of the photocurable transfer layer of the photocurable transfer sheet according to any one of claims 1 to 22 . On the surface of the optical information recording substrate having irregularities as recording pits and / or grooves and further having a reflective layer formed on the irregular surface, irregularities as recording pits and / or grooves are formed on the surface. An intermediate resin layer having a reflective layer formed on the uneven surface, the surface of the intermediate resin layer having no unevenness facing the reflective layer on the substrate surface, One or more other intermediate resin layers that are provided along the unevenness and further have an uneven surface and a reflective layer are arranged so that the surface without the unevenness of the intermediate resin layer faces the reflective layer of the already provided intermediate resin layer. An optical information recording medium provided on the reflective layer of the intermediate resin layer already provided along the unevenness thereof,
An optical information recording medium, wherein the intermediate resin layer is a cured layer of the photocurable transfer layer of the photocurable transfer sheet according to any one of claims 1 to 22 .

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