JPH01169755A - Production of optical information recording carrier - Google Patents

Abstract

PURPOSE:To obtain a recording carrier of smooth surface which is excellently heat-resistant and humidity-resistant by packing an ultraviolet curing resin solution including an organic peroxide between a metal mold having projecting and recessing part in its surface and a transparent plate processed with mold releasing treatment to process the hardening of the solution. CONSTITUTION:A forming cell is formed with the metal mold 1 having projecting and recessing part in its surface, the transparent plate 4, and a gasket 3. The transparent plate 4 is processed with mold release treatment or made of such a material that has itself property of mold releasing and lets ultraviolet rays transmit through itself. Then, in the cavity of the forming cell, the ultraviolet curing resin solution 2 including an organic peroxide into epoxyvinyl ester resin or unsaturated polyester, etc., is packed. And the resin solution 2 is irradiated by ultraviolet rays coming through the transparent plate 4 to harden, then it is separated from the mold 1 and the plate 4, and further, is made thermopolymerized by heating. As a result, a recording carrier highly heat- resistant, free from deforming due to absorption of water whose surface is smooth can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention applies to recording layers and reflective layers of optical information recording media such as optical disks and optical cards that enable information reproduction, recording, erasure, etc. using semiconductor laser light. Alternatively, the present invention relates to a molding method for an optical information recording carrier that supports a protective layer or the like.

[Problems with conventional technology]

In the past, methods of writing and reading information using magnetism have been widely used as a method for recording and reproducing information, but recently, a method of recording and reading high-density information using narrow beams such as laser light has been widely used. Optical information recording media such as optical disks and optical cards have been invented, some of which have already been put into practical use, and are attracting attention. This method makes it possible to record several thousand times more information on a medium of the same size than conventional magnetic methods, making it an extremely useful recording medium in an information-oriented society. There are various types of optical information recording carriers such as optical cards, CD-ROMs, optical disks, and magneto-optical disks. In addition, the required dimensions, shapes, etc. are also diverse. In order to meet these demands, it is necessary to manufacture optical information recording carriers suitable for the required dimensions, shapes, and recording methods. In addition, in the production of optical information recording carriers, tracking sensors? Is the formation of a guide groove (hereinafter referred to as pre-group) for this purpose the key? Becomes India. Among the resin materials used for the optical information recording carrier, thermoplastic resins can be used to form a plastic loop by injection molding. On the other hand, in thermosetting resins, pregroups are generally formed by a method called the 2P method. The 2P method is a method of forming a pre-group transfer layer made of an ultraviolet curable resin layer on a flat resin plate, and its contents are disclosed in Japanese Patent Application Laid-Open No. 51-1-1.
40601 (Polydarum), JP-A-53-116105
(Philips), JP-A-54-130902 (Philips), JP-A-54-138406 (Philips), JP-A-55-4793 (Philips), etc. However, the adhesion between the thermosetting resin flat plate and the ultraviolet curable resin layer is generally poor, which tends to cause defects during molding, and defects such as decreased adhesion, peeling, and blistering after a heat and humidity test. These defects make it unusable as an optical information recording carrier.

In order to solve the problems of the above-mentioned complicated 2P method, a radiation-curable resin is injected between a mold with an uneven surface and an opposing flat plate, and after curing the radiation-curable resin with radiation, the above-mentioned A method of manufacturing an optical information recording carrier having an uneven surface by removing a mold and a flat plate has been researched and disclosed in Japanese Patent Application Laid-Open No. 13307/1983.

However, since this method involves only curing by radiation, the radiation-curable resin cannot be cured by light, and the resulting optical information recording carrier has low heat resistance.

Significant deformation due to moisture absorption. Furthermore, in vacuum treatment for forming a recording layer or a reflective layer, unreacted monomers evaporate and the surface becomes rough, resulting in poor recording properties.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above points, and it has high heat resistance, less deformation due to moisture absorption, and has excellent recording characteristics without roughening of the substrate surface due to less evaporation of unreacted monomers during vacuum processing. The present invention provides a method for manufacturing an optical information recording carrier. Furthermore, the optical information recording carrier obtained here has an integral structure, and of course there is no problem such as peeling between two layers, which is the case with optical information recording carriers produced by the 2P method.

[Means for solving problems]

In order to achieve the above object, the present inventors manufactured optical disk substrates using various manufacturing methods and studied their characteristics. As a result, the inventors of the present invention discovered that after a specific UV-curable 411 fat liquid was cooled in the mold and then removed from the mold. The optical information recording carrier obtained by demolding and then performing Calo heat treatment has excellent heat resistance, is less deformed due to moisture absorption, and has less evaporation of unreacted monomers during vacuum treatment, so the surface of the substrate is less rough. The present invention was completed by discovering the fact that it has excellent recording properties.

That is, in order to solve the above-mentioned problems, the present invention fills an ultraviolet curable resin liquid between a mold having an uneven surface and a transparent plate facing the mold at a constant interval, and cures it by irradiating ultraviolet rays. After that, the cured resin plate having irregularities on one side is removed from the mold and the transparent plate, and then heat treated, in which a resin liquid containing an organic peroxide is used as the ultraviolet curable resin liquid, The present invention provides a method for producing an optical information recording carrier, characterized in that a transparent plate whose surface is treated with a release agent is used, which does not adhere to ultraviolet resin.

The mold having an uneven surface used in the present invention is made of Cr, F,
*, it can be made of any material such as Ni.

The transparent plate used in the present invention is a material that transmits ultraviolet rays, such as glass or transparent plastic, and the surface thereof has been subjected to a mold release treatment by applying a mold release agent or forming a mold release thin film by vapor deposition, or Any material, such as transparent polyolefin resin, which has better mold release properties than ultraviolet curing resins and which transmits ultraviolet rays, can be used.

Examples of the ultraviolet curing resin used in the present invention include epoxy vinyl ester resin, acrylic acid and/or methacrylic acid ester of polyester resin, acrylic acid and/or methacrylic acid ester of polyether resin, and acrylic acid and/or methacrylic acid ester of polybutadiene resin. These include methacrylic acid esters, polyurethane resins having an acrylic group and/or methacrylic group at the end of the molecule, and unsaturated polyester resins having 7 malic acid residues in the molecule.

Among these, epoxy vinyl ester resins with excellent heat resistance and low water absorption, and unsaturated polyesters are preferred. Since these ultraviolet curable resins have high viscosity, they are used after being diluted with a monomer reactive to ultraviolet rays, if necessary.

Reactive monomers include 1, for example, ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, n
-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,
Phenyl (meth)acrylate, phenylcelonorb (
Monofunctional monomers such as meth)acrylate, n-vinylpyrrolidone, inbornyl(meth)acrylate, nonclope/tazoenoxyethyl(meth)acrylatestyrene, diethylene glycolno(meth)acrylate, neobentylglycolno(meth)acrylate, 1
, 6-hexanezoolno(meth)acrylate, polyethylene glycolno(meth)acrylate, 2,2-
Bis(4-(meth)acryloyloxy, +?lyethyleneoxyphenyl)zolo/4'7,2+2-bis(
Bifunctional monomers such as 4-(meth)acryloyloxyphoriteropyleneoxyphenyl)propane, trifunctional monomers such as trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol tetra( Examples include tetrafunctional monomers such as meth)acrylate.

Photopolymerization initiators used in the present invention include Penzles,
Benzoins such as hentzuin, benzoin ethyl ether, benzoin isopropyl ether, pentwin isobutyl ether, benzophenones such as 1-hydroxycyclohexylbenzophenone, acetophenones, thioxanthones such as 2-chlorothioquinanthone, 2-methylthioxanthone, 2- Anthraquinones such as ethylanthraquinone and 2-methylanthraquinone,
These include benzyl ketals such as benzyl methyl ketal. The blending ratio of the photopolymerization initiator is preferably 0.1 to 10% by weight based on the ultraviolet curable resin liquid.

Examples of the organic peroxides used in the present invention include methyl ethyl ketone oxide, cyclohexanone oxide, 3,3,5-1-limethylcyclohexanone oxide, methylcyclohexanone oxide, and acetylaceto oxide. Ketone peroxides such as -oxide, 1,1-bis(t-butylperoxy): L3,5-trimethylcyclohexane, 1
, 1-bis(1-butylperoxy)cyclohexane,
Peroxyketals such as n-butyl 4,4-bis(t-butylno-9-oxy)noyalelate, 2,2-bis(t-butylperoxy)butane, t-butylhydroxide, cumene hydroperoxide , no isopropylbenzene hydro/ya monooxide, p
- Menthane Hydrono! -oxide, 2,5-trimethylhexane 2,5-cybidrobar oxide, 1,
Hydroveroxides such as 1,3.3-tetramethylbutyl hydroperoxide, t-butyl-4-oxide, t-butylcumyl/? - oxide,
Dicumyl peroxide, α,α'-bis(t-butylperoxyisopropyl)benzene, 2,5-methyl-2,5-zo(1-butylno-9-OΦsi)hexane, 2
．． Noalkyl/IP-oxides such as 5-dimethyl-2,5-zo(t-butylperoxy)hexyne-3, acetyl peroxide, imbutyryl peroxide, octanoyl/4'-oxide, decanoylno-9
-Oxide, lauroyl/'P -OxaiP, 3,
5.5- Trimethylhexanoyl monooxide,
benzoyl peroxide s2,4-) ri o o benzoyl peroxide, m-) noacylno-9-oxides such as luoyl peroxide, zoindelopyl peroxyno cartilinate, cy 2-ethylhexyl oxydicalde No-n-probyloxydicarbonate, 2-ethoxyethyl-9-oxydicargenate, nomethoxyisoglobyl-oxysocardenate, di(3-methyl-3-methoxygtyl)peroxy Dicarnate, acetylcyclohexylsulfonyl 4-oxide, etc.! -Oxydicaldenates, t-butyl luster-oxyacetate, t
-butylperoxyinzotyrate, t-butylperoxypinozylate, t-butylperoxy 2-ethylhexanoate, t-butylno-9-oxylaurate, t
- Pucirno! -oxybenzoate, 2.5-・dimethyl-L5-・zo(pen!ylnot-t-oxy)hexane (7) ``-oxyesters, azobis compounds such as α,α′-asohisisoptylonitrile, etc. It is.

The blending ratio of organic peroxide is 0 to the ultraviolet curing resin liquid.
．． 5 to 5% by weight is preferred.

In addition, a defoaming agent for the liquid resin, a surfactant to improve wetting with Stan A-, and a non-reactive thermoplastic resin to reduce curing shrinkage may be added to this ultraviolet curable resin liquid. Of course.

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

FIG. 1 is an explanatory diagram showing an example of the method for manufacturing an optical information recording carrier of the present invention. To obtain the optical information recording carrier of the present invention,
First, a molding cell as shown in FIG. 1(a) is formed using a mold l having an uneven surface, a transparent plate 4, and a gasket 3, and an ultraviolet curing resin liquid 2 is poured into the cavity of the resulting molding cell. Fill.

Next, ultraviolet rays are irradiated through the transparent plate 4 to cure the ultraviolet curable resin liquid.

Next, the ultraviolet curing resin plate 2 with the unevenness transferred to the surface
is released from the mold and the transparent plate (Fig. 1(b)).

Finally, the obtained ultraviolet curable resin plate is thermally polymerized by heating. The heat treatment is usually performed at a temperature range of 80°C or higher and 150°C or lower. If the heating temperature is 80° C. or lower, curing will be insufficient and the heat resistance and water resistance of the final product will decrease. If the heating temperature is 150° C. or higher, the ultraviolet curable resin plate will be deformed during the heat treatment.

〔Example〕

Hereinafter, a method for manufacturing an optical information recording carrier of the present invention will be explained with reference to Examples.

[Examples 1 to 7] A 0.3 m thick disokel mold with spiral irregularities on the surface and a 5 mm thick glass whose surface was treated with a fluorine-based mold release agent. 1. Form a board made of vinyl chloride facing a square with a spacing of 1.2-1. The ultraviolet curing resin liquid shown in Table 1 was injected into the molded cell. In this state, a No. 80 No. 1 high-pressure mercury lamp was irradiated for 40 seconds through the glass plate. Next, the ultraviolet curable resin plate was removed from the mold and the glass plate.

Seven optical information recording carriers were produced by heating at the temperatures shown in Table 1 for the times shown in Table 1. − of each optical information recording carrier obtained
The if-las transition point and water absorption rate were evaluated.

Further, a magneto-optical recording layer and a protective layer were formed on the obtained optical information recording carrier by magnetron sputtering under the following conditions.

Tb-Fe-Co based magneto-optical recording layer film formation conditions film thickness
800X Film forming method High frequency magnetron Rita method Chamber vacuum level 5X10'Torr introduction Ar
Voltage 3X10 Torr high frequency power
250W Target composition Tb 27” F @ 6
a ” CO5 (IL L%) S i , N4-based protective layer film formation conditions Film thickness 700X Film formation method High frequency magnetron-ritter method Chamber vacuum level 5X10 Torr introduction A
r/N 2 pressure lXl0 Torr(to
/10) High frequency power: 600W Target composition: 513X4 The characteristics of the magneto-optical recording medium obtained as described above were evaluated. A signal with a disk rotation speed of 1 MHz of 1800 rpm was written with a laser light intensity of 6 mW and reproduced with 1 mW.

-Y light quantity signal was reproduced, and the CN ratio was measured using a spectrum analyzer under the condition of a band width of 30 kHz.

[Comparative Examples 1 to 6] The same molding process as in Examples 1 to 7 was performed using the ultraviolet curing resin shown in Table 2, and heating was performed at the temperature shown in Table 2 for the time shown in Table 2 to produce optical information recording carriers. . However, comparative example 6
A glass plate whose surface was not treated with a release agent was used as a transparent plate. The glass transition point and water absorption rate of the obtained optical information recording carrier were evaluated. Further, a magneto-optical recording layer was formed in the same manner as in Examples 1 to 7, and the C of the obtained magneto-optical recording medium was
The N ratio was measured.

(Evaluation) Examples 1 to 4 showed sufficient heat resistance and low water absorption, and
The recording characteristics are also good. In Example 5, a long heat treatment was required to obtain sufficient heat resistance, but this was not a problem. Examples 6 and 7 are somewhat inferior in heat resistance and water absorption, but are at a level that causes no problems under normal usage conditions.

Comparative Examples 1 to 3 were either not subjected to heat treatment or the treatment temperature was too low, resulting in extremely poor heat resistance, water absorption, and recording properties, making them unsuitable for practical use. Comparative Example 4 was deformed during the heat treatment because the heat treatment temperature was too high. Comparative Example 5 does not contain an organic peroxide in the ultraviolet curable resin, so even after heat treatment, the heat resistance and water absorption rate are poor and it cannot be put to practical use. In Comparative Example 6, after curing the ultraviolet curing resin liquid, when the resin plate was removed from the mold and the glass plate, it was impossible to remove it from the lath plate.

・Di/7゛'' village 30 parts of acrylic acid ester of bifunctional resin with epoxy equivalent weight 300, 2,2-bis(4-methacryloyloxy zopropyleneoxyphenylene) fronoyane 3 o parts, 30 parts of 1.6-hexanediol noacrylate, 10 parts of styrene, 0.5 parts of Irgacure 651 (manufactured by Chipaga Iggy), 1 part of Perbutyl 0 (manufactured by NOF Corporation)*2 Unsaturated polyester resin 7 Parilight FG-38
7 (manufactured by Dainippon Ink and Chemicals Co., Ltd.) 100 parts, Ilga Cure 184 (manufactured by Ciba Geigy) 1 part, Percure SA (manufactured by Nippon Oil & Fats Co., Ltd.) 1 part. Acrylic acid ester 60 parts, trimethyyl 0-lua' 6
/f 10 parts of triacrylate, 30 parts of styrene, 1 part of ILGA CURE 184 (manufactured by CHIPAGAII Co., Ltd.), NOJ? −
Cure 5A1i Tei 4 30 parts of polytetramethionone glycol noacrylate with a number average molecular weight of 111,000, 20 parts of trimethylolnoropane triacrylate, 50 parts of neo-4-entyl glycol diacrylate, Il I Cure 6
510.5 parts, Nof-Kair SAI Department Vehicle 5, 30 parts of bifunctional urethane acrylate with a number average molecular weight of 2000, 30 parts of trimethylol glono 1/triacrylate, 1,
20 parts of 6-hexanolnoacrylate, 20 parts of styrene, 6510.5 parts of 6-hexane air, 1 part of nokuki air SA 6. A test piece measuring 75 cm x 5 mm was prepared using the DSC method and placed in boiling water for 24 hours. Measured by immersion *8 Ultraviolet curing resin 1 minus reverbbutyl O [Effects of the invention] As is clear from the above explanation, the manufacturing method of the present invention has high heat resistance, less deformation due to moisture absorption, and , provides a method for producing an optical information recording carrier that can obtain excellent recording properties without roughening the substrate surface due to less evaporation of unreacted monomers during vacuum processing, and its industrial applicability is extremely high. It is.

[Brief explanation of the drawing]

FIGS. 1(,) and 1(b) are process explanatory diagrams for carrying out the method of the present invention.

Claims (3)

[Claims] (1) A method for manufacturing an optical information recording carrier used in an optical information recording medium such as an optical disk or an optical card, in which a mold having an uneven surface and a transparent plate placed opposite the mold at a constant interval are provided. In this method, the UV-curable resin liquid is filled into a mold, the resin plate having unevenness on one side is removed from the mold and the transparent plate, and then heat-treated. A method for manufacturing an optical information recording carrier, characterized in that a resin liquid containing an organic peroxide is used as the transparent plate, and a transparent plate whose surface has been subjected to mold release treatment or a transparent plate that does not adhere to ultraviolet resin is used. (2) The method for producing an optical information recording carrier according to claim 1, characterized in that the heat treatment temperature is 80°C or more and 150°C or less. (3) The method for producing an optical information recording carrier according to claim 1, characterized in that the ultraviolet curing resin is an epoxy vinyl ester resin and/or an unsaturated polyester resin.