JPS6074133A - Optical information recording carrier - Google Patents

Abstract

PURPOSE:To obtain a recording carrier which has a long life in high-humidity and high- temp. environment and has excellent trasfer efficiency by depositing a radiation polymerized and cured material layer consisting of a monomer reactive with radiant ray and a specific reactive oligomer on a base plate and inscribing optical signal pits on the surface of said cured material layer. CONSTITUTION:A radiation polymerized and cured material layer of a monomer reactive with radiant ray and a reactive oligomer which is the acrylic acid-or methacrylic acid-modified matter of the compd. bound with liquid epoxide at both terminals of a polybutadiene chain is deposited on a base plate and optical signal pits are inscribed on the surface of such radiation polymerized and cured material layer, by which a recording carrier is obtd. The adhesion to the base plate, transfer efficiency and releasability from a die for transfer are improved by using the reactive oligomer. An example of the basic constitutional formula of the reactive oligomer is expressed by the formula. Said oligomer is the mixture composed of the monoacrylate or monomethacrylate of which the ester chain of the reactive monomer has a hydrogen bondable functional group and the polyhydric acrylate or polyhydric methacrylate having non hydrogen bondable functional group. The weight ratio of the reactive monomer and the reactive oligomer is made 30:70-95:5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention can be used as a digital audio disc, a video disc, or a disc memory cap.

For more details regarding the optical information recording carrier, please refer to
Optical information recording carriers (ζ-related) that have excellent adhesion to the plate, can faithfully transfer signals engraved on the master disk or transfer matrix such as Sukun Riichi, and have excellent productivity.

[Technical background of the invention and its problems]

Generally, an information recording carrier for a digital audio disc or video disc is one in which optical information is imprinted on the disc surface as a large number of minute signal bits.

Also, recording/reproducing optical information, A2. Yes, delete it fji4
The information recording carrier 1 for a disk memory is usually not one in which the optical information itself is engraved in bits on the disk surface, but a guide groove (f groove) for high-definition tracking of the optical head. ) is engraved on the surface of the optical disc.

Conventionally, the method for mass-producing optical information recording carriers with these fine signal bits and guide grooves is to first create a transfer master mold with signal bits or guide grooves, and then mold this into a mold. As the mold, injection molding or compression molding of plastics is used.

However, the injection molding method or the compression molding method has disadvantages in that the molding machine is large and the transfer accuracy is low.

In order to improve these points, a transfer method in which signal bits are formed in a single layer of radiation-curable lacquer was researched by Polydulum Co., Ltd. and Filligs Co., Ltd., and the details were published in JP-A-51
-140601 (Polydarum), JP-A-53-116
105 (Philips), JP-A-54-130902 (
(Philips), JP-A-54-138'406 (Philips), JP-A-5J-4793 (Philips), etc.

This method involves applying a thin layer of liquid radiation-curable lacquer on the surface of a master mold for transfer, such as a metal mold that has been transferred from the master master (electroforming method).
A colorless and transparent plastic substrate is placed on top of this single layer of lacquer, and while the single layer of lacquer is held in place, radiation is irradiated to harden the single layer of lacquer.

Next, the single layer of cured lacquer onto which the signal bits have been transferred and the plastic substrate integrally bonded thereto are peeled off from the transfer matrix to produce an information recording carrier.

However, in conventional information recording carriers, a relatively low molecular weight, colorless and transparent material with a viscosity of 100 CP or less and an average molecular weight of at most 500 is used as a radiation-curable lacquer. board)
Poor adhesion. Therefore, when the information recording carrier is used for a long time, especially when used at high temperatures or in a high-temperature environment, there is a problem in that the radiation-cured lacquer layer gradually peels off from the interface with the support substrate. In addition, conventional radiation-curable lacquers shrink considerably during curing, making it impossible to achieve a 1:1 bit transfer from the transfer mold, resulting in insufficient transfer efficiency, and poor releasability from the transfer mold. There were problems such as poor productivity due to poor quality.

[Purpose of the invention]

The present invention has been made in view of the above points, and even when used for a long period of time in a high humidity and high temperature environment, the adhesion between the radiation cured lacquer layer on which signal bits are formed and the support substrate is maintained, resulting in a long service life. It is an object of the present invention to provide an information recording carrier which can be used for various purposes, has excellent transfer efficiency of signal bits and guide grooves, and has improved productivity.

[Summary of the invention]

In order to achieve the above object, the present inventors produced optical information recording carriers by radiation polymerizing various radiation-curable lacquers between a transfer mold and a support substrate, and as a result of studying their characteristics, they found that Optical information recording carriers obtained from radiation-curable lacquers have poor adhesion to the support substrate, transfer efficiency,
The present invention was completed based on the discovery that productivity is extremely good.

That is, the optical information recording carrier of the present invention is provided on a support substrate; a radiation-reactive monomer; and a reactive oligomer which is an acrylic acid or methacrylic acid modified product of a compound in which liquid I oxide is bonded to both ends of a polybutadiene chain. A layer of radiation-polymerized cured material is deposited; and an optical signal bit is engraved on the surface of the radiation-polymerized cured material layer.

The support base material used is an essential element for reinforcing and protecting the radiation polymerized cured product layer, which has low mechanical strength.

Examples of the support base material include acrylic, acetate,
Polymer materials such as phenol and epoxy resin, glass, S
10. , etc. Ceramics, At, Zn.

Examples include plates, disks, sheets, and films of metal such as Cu.

In the present invention, the use of the reactive oligomer is an essential element for improving the adhesion to the support substrate, transfer efficiency, and releasability from the transfer mold.

This reactive oligomer is a compound of acrylic acid or methacrylic acid in which liquid epoxide is bonded to both ends of a polybutadiene chain [hereinafter, "acrylic acid or methacrylic acid" is simply referred to as "(meth)acrylic acid". ] It is a metamorphosed product.

An example of the basic structural formula of a reactive oligomer is as follows.

. =0-1N
This is an example of acrylic acid modification of a compound bound to a liquid epoxide.

The polybutadiene preferably has a sitatsuene structural unit repeating number n of 5 to 70. On the other hand, if n is less than 5, transfer efficiency and mold release properties will decrease.

This is because if n exceeds 60, the adhesion to the support substrate will be insufficient.

Liquid epoxide is a bisphenol A type compound like the above formula. It is not limited to oxides, and may be of aliphatic type.

A compound in which a liquid epoxide is bonded to both ends of a polybutadiene chain, which is a raw material for the reactive oligomer,
Examples of liquid epoxides that are bisphenol A type epoxides include Nl5SO epoxin gPB-12B (epoxy equivalent: 450 to 600, manufactured by Nippon Soda).
), gpn13 (epoxy equivalent 600-780
), EPB14 (epoxy equivalent weight 400-550
), EPB17 (English equivalent: 300-38
0) etc., and the liquid epoxide is an aliphatic epoxide, for example, gPB2 manufactured by Nippon Soda
3 (epoxy equivalent 750-900), gPB27
(epoxy equivalent: 200 to 300).

The reactive oligomers contained in the radiation-curable lacquer of the present invention are those oligomers further modified with (meth)acrylic acid to make them capable of radical polymerization.

The present inventors had previously proposed radiation-curable polygetatsuene as a reactive oligomer suitable for these uses, but this reactive oligomer was only soluble in nonpolar reactive monomers and lacked versatility. .

However, as in the present invention, the acrylic-modified reactive oligomer whose main skeleton is made by adding liquid epoxy to polygetatsuene is soluble in almost all reactive monomers, so it can be prepared into a lacquer suitable for the application. easy. I cut it,
The cured film of the lacquer containing this reactive meligomer is transparent to laser light.

These reactive oligomers are monoesters of (meth)acrylic acid, which are called reactive monomers because of their high viscosity.
It is used after being diluted with diester, triester, tetraester, etc. Examples of reactive monomers include ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, n-butyl (meth)acrylate, hexyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, queethylene glycol di(meth)acrylate, Examples include triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, trimethylolgloin triacrylate, inkyrythritol triacrylate, pentaerythritol tetraacrylate, etc. Preferably, the ester chain has a hydrogen-bonding function. It is used as a mixture of a mono(meth)acrylate having a group and a poly(meth)acrylate having no hydrogen-bonding functional group.

This is because by using such a mixture of reactive monomers, the adhesion and releasability between the support substrate and the radiation-polymerized cured material layer can be improved, and moreover, the radiation-curable lacquer can be made odorless. . From the viewpoint of improving adhesion, mold releasability, and odorlessness, the weight mixing ratio of mono(meth)acrylate having a hydrogen-bonding functional group and polyhydric (meth)acrylate having no hydrogen-bonding functional group in this mixture is The ratio is preferably 5:95 to 60:40.

Further, the weight mixing ratio of the reactive monomer and the reactive oligomer in the radiation-curable lacquer is 30:70 to 95:5.
It is wise to set the ratio to be 50:50 to 95, more preferably 50:50 to 95.
:5. If the reactive oligomer content exceeds 70% by weight, the viscosity of the lacquer liquid will become too high, making it difficult to apply a thin layer onto the transfer mold, and air bubbles may form in the lacquer liquid during application. On the other hand, if the content is less than 5% by weight, the transfer efficiency, the adhesion between the support substrate and the cured material layer, the mold releasability, etc. will deteriorate.

Next, a method for manufacturing an optical information recording carrier according to the present invention will be explained with reference to the accompanying drawings.

The figure is an explanatory diagram showing an example of the method for manufacturing an optical information recording carrier of the present invention.

In order to obtain the optical information recording carrier of the present invention, first, a transfer mold 2 is prepared.
is prepared, and the radiation-curable lacquer layer 3 is provided on the optical information recording surface of the mold 2 by, for example, a wet coating method.

A transparent support substrate 4, for example, is then placed on top of this lacquer layer 3. At that time, when a glass plate or a 5102 plate is used as the transparent support substrate 4, it is preferable to subject the surfaces thereof to a surface treatment with a silane cassilling agent, a keran coupling agent, or the like.

With the lacquer layer 3 sandwiched between the substrate 4 and the transfer screen 2, an electron beam, r
Irradiate with radiation 5 such as X-rays, X-rays, and ultraviolet rays, and apply a layer of lacquer 5.
harden. If the radiation used is ultraviolet radiation, it is preferred to add a number of photoinitiators to the radiation-curable lacquer beforehand. Such photoinitiators include e.g.
oy-2-(o-ethoxycarvinyl)oxime,
Examples include 2.2-dimethoxy-2-thenylacetophenone and benzoin isobutyl ether.

Finally, the cured lacquer layer 5 onto which the signal bits 1 have been transferred is released from the transfer mold 2 together with the substrate 4, to obtain the optical information recording carrier of the present invention.

[Sounding adverse effect]

As is clear from the above description, the optical information recording carrier of the present invention has excellent adhesion to the support substrate, and the signals engraved on the transfer mold are faithfully transferred, and the radiation-curable lacquer used Since it is odorless and has good releasability from the p1 transfer mold, it has the effect of improving productivity, and its industrial applicability is extremely large.

[Embodiments of the invention]

Hereinafter, the optical information recording carrier of the present invention will be explained along with examples.

In addition, all "parts" described in the examples shall represent heavy parts.

Example reactive oligomer: acrylic-modified EPB14
(manufactured by Nippon Soda), 70 parts of triethylene glycol diacrylate, 20 parts of hydroxyethyl methacrylate, and 2 parts of 2,2-dimethoxy-2-phenylacetophenone as a photoinitiator were mixed to prepare a radiation-curable lacquer. did.

Apply this lacquer liquid to a nickel skunk mold, which is a transfer mold.
After filling the gap between the acrylic resin and the acrylic support substrate, ultraviolet rays were irradiated. After the lacquer liquid had hardened, the substrate was peeled off from the interface with the single layer of lacquer and the nickel stanoxide layer to produce an information recording carrier. At this time, the mold separation between the cured lacquer layer and the nickel stamper and the signal transferability were good.

In addition, cross-cutting improves the adhesion between the cured lacquer layer and the acrylic board! Test (ASTMD-3359-76)
When examined, none of the 100 samples showed peeling.

Application Example When a metal reflective film is provided on the lacquer hardened layer of the information recording carrier of the present invention, a video disc that can be optically read by changing the reflectance can be obtained. Still, using the present invention, it is possible to create a disk memory that can be optically written and read by not only transferring signal pits but also transferring 6 guide grooves in a circular pattern.

[Brief explanation of drawings]

The figure is an explanatory diagram showing an example of the method for manufacturing an optical information recording carrier of the present invention. DESCRIPTION OF SYMBOLS 1... Signal bit, 2... Transfer mold, 3... One layer of radiation-curable lacquer, 4... Transparent support substrate, 5...
·radiation.

Claims (1)

[Claims] 1. On a support substrate: a radiation-reactive monomer and a radiation-reactive oligomer that is an acrylic acid or methacrylic acid modified product of a compound in which a liquid epoxide is bonded to both ends of a polybutyl diene chain. A layer of polymerized cured material is deposited; optical signal pits are engraved on the surface of the layer of radiation-polymerized cured material. Optical information recording carrier to save the day. 2. The ester chain of the reactive mono-1-- is! ! ,
J [The relationship between a monoacrylic l/-1- or monomethacrylate having a functional group and a polyvalent acrylate or polyvalent methacrylate-1 having no hydrogen-bonding functional group. The optical information storage carrier according to claim 1, which is a composite. 36 Claims centering around χ
1 top ga ρ rust) -) V74 Yoi Takune 3 - Feng Sobushiichi 4,
The weight ratio of the reactive monomer to the reactive oligomer is 5.
0:50~95:5! 1￥Claims No. 1
A collection of 16 optical reports listed in the section.