JPH01232552A - Optical disk substrate - Google Patents
Optical disk substrateInfo
- Publication number
- JPH01232552A JPH01232552A JP63057692A JP5769288A JPH01232552A JP H01232552 A JPH01232552 A JP H01232552A JP 63057692 A JP63057692 A JP 63057692A JP 5769288 A JP5769288 A JP 5769288A JP H01232552 A JPH01232552 A JP H01232552A
- Authority
- JP
- Japan
- Prior art keywords
- substrate
- resin
- recording
- silicone resin
- film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000758 substrate Substances 0.000 title claims abstract description 35
- 230000003287 optical effect Effects 0.000 title claims abstract description 29
- 229920005989 resin Polymers 0.000 claims abstract description 18
- 239000011347 resin Substances 0.000 claims abstract description 18
- 229920002050 silicone resin Polymers 0.000 claims abstract description 17
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 claims abstract description 8
- 229920001187 thermosetting polymer Polymers 0.000 claims abstract description 6
- 230000037303 wrinkles Effects 0.000 abstract description 13
- 239000011521 glass Substances 0.000 abstract description 7
- 229920002554 vinyl polymer Polymers 0.000 abstract 2
- 239000011248 coating agent Substances 0.000 abstract 1
- 238000000576 coating method Methods 0.000 abstract 1
- 238000005336 cracking Methods 0.000 abstract 1
- 238000004544 sputter deposition Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000006866 deterioration Effects 0.000 description 4
- 238000001746 injection moulding Methods 0.000 description 4
- 229920000178 Acrylic resin Polymers 0.000 description 3
- 239000004925 Acrylic resin Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000006082 mold release agent Substances 0.000 description 3
- 229920005668 polycarbonate resin Polymers 0.000 description 3
- 239000004431 polycarbonate resin Substances 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 239000006087 Silane Coupling Agent Substances 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- FWDBOZPQNFPOLF-UHFFFAOYSA-N ethenyl(triethoxy)silane Chemical compound CCO[Si](OCC)(OCC)C=C FWDBOZPQNFPOLF-UHFFFAOYSA-N 0.000 description 2
- 229910010272 inorganic material Inorganic materials 0.000 description 2
- 239000011147 inorganic material Substances 0.000 description 2
- 230000001678 irradiating effect Effects 0.000 description 2
- 238000010030 laminating Methods 0.000 description 2
- 229920005672 polyolefin resin Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000007822 coupling agent Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 229920003217 poly(methylsilsesquioxane) Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- -1 siloxane skeleton Chemical group 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は情報記録などに用いられる光ディスク基板に関
する。Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to an optical disc substrate used for information recording and the like.
（従来の技術）
従来より光学的記録媒体（光ディスク）の基板材料とし
ては、ガラス、アクリル樹脂、ポリカーボネート樹脂、
エポキシ樹脂、ポリオレフィン樹脂などが用いられてい
る。こうした光ディスクでは、高密度な記録を達成する
ために、その基板−ヒに光学的案内溝やビットなどが形
成される。そして、このような基板上に下地層、記録膜
、反射膜などが形成される。(Prior Art) Conventionally, substrate materials for optical recording media (optical disks) include glass, acrylic resin, polycarbonate resin,
Epoxy resin, polyolefin resin, etc. are used. In such optical discs, optical guide grooves, bits, etc. are formed on the substrate in order to achieve high-density recording. Then, a base layer, a recording film, a reflective film, etc. are formed on such a substrate.
上記のような基板としては従来、おおまかに分類して以
下の３通りの方法により作製されたものが知られており
、長所もあるがそれぞれ欠点がある。Conventionally, the above-mentioned substrates have been roughly classified and manufactured by the following three methods, each of which has advantages but also has disadvantages.
■案内溝などの形状に対応する凹凸が刻設されたスタン
パを含む金型内に、溶融した樹脂を射出して固化させ、
案内溝などを転写する方法、この射出成形による方法で
は、例えばアクリル樹脂、ポリカーボネート樹脂、ポリ
オレフィン樹脂などの熱硬化性樹脂が用いられる。■ Molten resin is injected into a mold containing a stamper that is engraved with unevenness that corresponds to the shape of the guide groove, etc., and then solidified.
In the injection molding method of transferring guide grooves and the like, thermosetting resins such as acrylic resins, polycarbonate resins, and polyolefin resins are used.
この射出成形による方法は量産性に優れている。その反
面、光学特性である複屈折の均一性が悪い、基板が変形
する、通気性であることから記録膜の腐食を招くなどの
問題がある。また、スパッタリングで記録膜などを形成
する際、上記のような耐熱性の低い樹脂からなる基板が
軟化するため、記録膜などとの密着性が悪く、記Ｑ膜に
シワやクラックが発生しやすい、しかも、スタンパなど
との剥離性の改みを目的として、内部離型剤を添加する
ため、記録膜などとの密着性が一層悪くなる。This injection molding method is excellent in mass production. On the other hand, there are problems such as poor uniformity of birefringence, which is an optical property, deformation of the substrate, and corrosion of the recording film due to its air permeability. In addition, when forming a recording film etc. by sputtering, the substrate made of resin with low heat resistance as mentioned above becomes soft, resulting in poor adhesion to the recording film etc., making the Q film prone to wrinkles and cracks. Moreover, since an internal mold release agent is added for the purpose of improving the releasability with a stamper etc., the adhesion with the recording film etc. becomes worse.
（２）ガラスなどの透明基板とスタンパとの間に紫外線
硬化型樹脂を流し込み、紫外線を照射して樹脂を硬化さ
せ、基板に固着させて案内溝などを有する硬化型樹脂層
を形成する、ｚＰ法と呼ばれる方法、上記紫外線硬化型
樹脂としては、例えばアクリル系樹脂、エポキシ系樹脂
などがある。(2) Injecting an ultraviolet curable resin between a transparent substrate such as glass and a stamper, curing the resin by irradiating it with ultraviolet rays, and fixing it to the substrate to form a curable resin layer having guide grooves, etc., zP. Examples of the ultraviolet curable resin include acrylic resin and epoxy resin.
この２Ｐ法は射出成形法よりも量産性に劣る。This 2P method is inferior to the injection molding method in terms of mass productivity.
また、未露光部に未反応物（モノマーなどの低分子成分
）が残留するため、これを洗浄により除去しなければな
らず、しかも洗浄後に汚れが残りやすい、そして、スパ
ッタリングで記録膜などを形成する際、未反応物が蒸発
し、膜付きが困難である。また、樹脂の耐熱性が低い場
合には、上記と同様に記録膜などにシワやクラックが発
生しやすい、なお、２Ｐ法で作製した基板を注意深く取
り扱えば、膜付は時には記録膜などのシワやクラックの
発生を防止することもできるが、長期間経過するとシワ
やクランクが発生してしまうことがある。In addition, unreacted substances (low-molecular components such as monomers) remain in the unexposed areas, which must be removed by cleaning, and dirt tends to remain after cleaning, and recording films are formed by sputtering. When doing so, unreacted substances evaporate, making it difficult to form a film. In addition, if the heat resistance of the resin is low, wrinkles and cracks are likely to occur in the recording film, etc., as mentioned above.In addition, if you handle the substrate made by the 2P method carefully, sometimes the recording film, etc. will wrinkle when the film is attached. Although it is possible to prevent the occurrence of cracks and scratches, wrinkles and cracks may occur over a long period of time.
■スタンパを含む金型内に１例えばエポキシ系樹脂など
の反応性樹脂を注型し、反応させて硬化する方法。■A method in which reactive resin, such as epoxy resin, is poured into a mold containing a stamper and cured by reaction.
この注型法では反応時に生じる内部歪の発生による光学
特性の低下を防ぐため、場合によっては数時間にも及ぶ
長時間の硬化時間を要し、量産性に劣る。また、スタン
パなどとの剥離性の改善を目的として、樹脂中の極性基
を減少させたり、内部離型剤を添加するため、記Ｑ膜な
どとの密着性が悪くなるという欠点を有する。また、樹
脂の耐熱性が低い場合には、上記と同様に記録膜などに
シワやクラックが発生しやすい。This casting method requires a long curing time, sometimes up to several hours, in order to prevent deterioration of optical properties due to internal strain generated during reaction, and is poor in mass production. In addition, since the polar groups in the resin are reduced or an internal mold release agent is added for the purpose of improving the releasability from the stamper, etc., there is a drawback that the adhesion with the Q film etc. is deteriorated. Furthermore, when the heat resistance of the resin is low, wrinkles and cracks are likely to occur in the recording film, etc., as described above.
（発明が解決しようとする課題）
以上のように従来の光ディスク基板には種々の問題があ
り、特に記録膜などにシワやクラックが発生しやすく、
記録特性が劣化することが最大の問題となっている。(Problems to be Solved by the Invention) As mentioned above, conventional optical disc substrates have various problems, and in particular, wrinkles and cracks are likely to occur in the recording film, etc.
The biggest problem is that recording characteristics deteriorate.
本発明は上記課題を解決するためになされたものであり
、膜付けされる記録膜などにシワやクラックを発生させ
ることのない光ディスク基板を提供することを目的とす
る。The present invention has been made to solve the above problems, and an object of the present invention is to provide an optical disc substrate that does not cause wrinkles or cracks in the recording film or the like on which the film is attached.
［発明の構成］
（課題を解決するための手段と作用）
本発明の光ディスク基板は、透明基板上に設けた樹脂層
に案内溝、ビットなどの凹凸形状を転写した光ディスク
基板において、上記樹脂層が熱硬化性のビニル基含有シ
リコーン樹脂からなることを特徴とするものである。[Structure of the Invention] (Means and Effects for Solving the Problems) The optical disc substrate of the present invention is an optical disc substrate in which uneven shapes such as guide grooves and bits are transferred to a resin layer provided on a transparent substrate. is characterized in that it is made of a thermosetting vinyl group-containing silicone resin.
本発明に係る光ディスク基板は、ガラスなどの透明基板
先にビニル基含有シリコーン樹脂をスピンナなどで塗布
し、乾燥した後、スタンパなどの原盤を加勢圧着して、
透明基板上のシリコーン樹脂に案内溝やビットなどの凹
凸を転写するとともに硬化させ、原盤から剥離すること
により作製することができる。なお、ガラスなどの透明
基板とシリコーン樹脂との密着性を向上させるために。The optical disc substrate according to the present invention is produced by applying a vinyl group-containing silicone resin onto a transparent substrate such as glass using a spinner, drying it, and then applying force and pressure to a master such as a stamper.
It can be produced by transferring unevenness such as guide grooves and bits onto a silicone resin on a transparent substrate, curing it, and peeling it off from the master. In addition, to improve the adhesion between a transparent substrate such as glass and silicone resin.
透明基板をシランカップリング剤で処理してもよい、同
様に、シリコーン樹脂°と記録膜などとの密着性を向上
させるために、シランカップリング剤の蒸気中でシリコ
ーン樹脂を加熱処理したり適当な波長の光を照射するこ
とにより、その表面にカップリング剤を反応させてもよ
い。The transparent substrate may be treated with a silane coupling agent.Similarly, in order to improve the adhesion between the silicone resin and the recording film, the silicone resin may be heated in the vapor of the silane coupling agent or treated with an appropriate treatment. A coupling agent may be reacted on the surface by irradiating light with a certain wavelength.
本発明の光ディスク基板を構成するシリコーン樹脂は、
スタンパなどとの剥離性が良好であるので、内部離型剤
を用いる必要はない、また、シリコーン樹脂は耐熱性が
高いので、スパッタリングで記録膜を形成する際に軟化
することはない、更に、シリコーン樹脂のシロキサン骨
格は、記録膜などの無機材料との親和性がよい、したが
って、スパッタリングで記録膜などを形成しても、シワ
やクラックが発生しにくい、その他、上記のように工程
が簡単であるうえ、ビニル基含有シリコーン樹脂に対し
て用いられる過酸化物などの反応開始剤として適当なも
のを選択することにより、反応温度や反応待間をある程
度自由に設定することができるので、量産性に関しても
有利性がある。The silicone resin constituting the optical disc substrate of the present invention is
There is no need to use an internal mold release agent because it has good releasability with stampers, etc. Also, silicone resin has high heat resistance, so it will not soften when forming a recording film by sputtering. The siloxane skeleton of silicone resin has good affinity with inorganic materials such as recording films.Therefore, even when recording films are formed by sputtering, wrinkles and cracks are less likely to occur, and the process is simple as described above. In addition, by selecting an appropriate reaction initiator such as peroxide used for vinyl group-containing silicone resin, the reaction temperature and reaction waiting time can be set to a certain degree, making mass production possible. There are also advantages in terms of sex.
なお、耐熱性だけに着目すれば、通常の熱硬化性樹脂を
用いることも考えられる。しかし１通常の熱硬化性樹脂
は極性基のためにスタンパなどとの剥離性が悪く、また
記録膜などの無機材料とのの親和性が悪いものが多いた
め、上記のような効果を得ることは困難である。In addition, if attention is paid only to heat resistance, it is also possible to use a normal thermosetting resin. However, 1. Because ordinary thermosetting resins have polar groups, they have poor releasability from stampers, etc., and many have poor compatibility with inorganic materials such as recording films, so it is difficult to obtain the above effects. It is difficult.
（実施例） 以下、本発明の詳細な説明する。(Example) The present invention will be explained in detail below.
実施例１
直径 １３０ｓ層、厚さ １．２ｍ鳳の強化ガラス基板
上に、スピンナでビニル基含有シリコーン樹脂（東芝シ
リコーン製、ＹＲ３２２４）を塗布した後、１００℃で
１０分間乾燥した０次に、ガラス基板上のビニル基含有
シリコーン樹脂に、案内溝が形成されたスタンパを圧着
し、１７０℃で１５分間加熱してシリコーン樹脂を硬化
させた後、スタンパを剥離して光ディスク基板を得た０
次いで、スパッタ法によりＳｉ３Ｎ４の下地層、ＴｂＣ
ｏの記録膜、Ａ文の反射膜を順次積層して光ディスクを
作製した。Example 1 A vinyl group-containing silicone resin (manufactured by Toshiba Silicone, YR3224) was coated on a reinforced glass substrate with a diameter of 130s and a thickness of 1.2m using a spinner, and then dried at 100°C for 10 minutes. A stamper with a guide groove formed therein was pressure-bonded to a vinyl group-containing silicone resin on a glass substrate, and after heating at 170° C. for 15 minutes to harden the silicone resin, the stamper was peeled off to obtain an optical disk substrate.
Next, by sputtering, a Si3N4 underlayer, a TbC
An optical disc was fabricated by sequentially laminating a recording film (o) and a reflective film (a).
実施例２
実施例１と同様な方法で作製された光ディスク基板をビ
ニルトリエトキシシラン蒸気中、２００℃で１時間加熱
処理した。その後、実施例１と同様にスパッタ法により
下地層、記録膜、反射膜を順次積層して光ディスクを作
製した。Example 2 An optical disk substrate prepared in the same manner as in Example 1 was heat-treated at 200° C. for 1 hour in vinyltriethoxysilane vapor. Thereafter, in the same manner as in Example 1, a base layer, a recording film, and a reflective film were sequentially laminated by sputtering to produce an optical disc.
実施例３
実施例１と同様な方法で作製された光ディスク基板にビ
ニルトリエトキシシラン蒸気中で紫外線を１０分間照射
する処理を行った。その後、実施例１と同様にスパッタ
法により下地層、記録膜、反射膜を順次積層して光ディ
スクを作製した。Example 3 An optical disk substrate prepared in the same manner as in Example 1 was treated with ultraviolet rays for 10 minutes in vinyltriethoxysilane vapor. Thereafter, in the same manner as in Example 1, a base layer, a recording film, and a reflective film were sequentially laminated by sputtering to produce an optical disc.
比較例
ポリカーボネート樹脂を用いて射出成形により作製され
た光ディスク基板上に、実施例１と同様にスパッタ法に
より下地層、記録膜１反射膜を順次積層して光ディスク
を作製した。Comparative Example An optical disc was manufactured by sequentially laminating a base layer and a recording film 1 reflective film by sputtering in the same manner as in Example 1 on an optical disc substrate manufactured by injection molding using a polycarbonate resin.
以上のようにして作製された実施例１〜３及び比較例の
光ディスクについて、膜付は直後の記録膜などを顕微鏡
で観察した。また、各光ディスクを８０℃ ９０％ＲＨ
で２４時間保持した後、室温で１時間保持する操作を４
サイクル繰り返し、更に８０％ＲＨで９６時間保持する
加速劣化試験を行った後、記録膜などを“顕微鏡で観察
した。Regarding the optical discs of Examples 1 to 3 and Comparative Example produced as described above, the recording film and the like immediately after being coated with the film were observed using a microscope. In addition, each optical disc was heated at 80°C and 90%RH.
After holding for 24 hours at room temperature, hold at room temperature for 1 hour.
After repeated cycles and an accelerated deterioration test in which the film was held at 80% RH for 96 hours, the recording film and other parts were observed under a microscope.
その結果、比較例の光ディスクでは、膜付は直後に記録
膜の一部にシワ、クラックが発生しており、加速劣化試
験後には記録膜の全面にシワ、クラ７りが発生していた
。これに対し、実施例１〜３の光ディスクでは膜付は直
後も、加速劣化試験後にも記録膜にシワやクラックの発
生は全く認められなかった。As a result, in the optical disc of the comparative example, wrinkles and cracks occurred in a part of the recording film immediately after the film was attached, and wrinkles and cracks occurred on the entire surface of the recording film after the accelerated deterioration test. On the other hand, in the optical discs of Examples 1 to 3, no wrinkles or cracks were observed in the recording film either immediately after the film was attached or after the accelerated deterioration test.
［発明の効果］
以−Ｌ詳述したように本発明の光ディスク基板を用いれ
ば、その表面に形成される記録膜には長期間にわたって
シワやクラックが発生することがなく、良好な記録特性
を維持することができる。[Effects of the Invention] As described in detail below, if the optical disc substrate of the present invention is used, the recording film formed on its surface will not develop wrinkles or cracks over a long period of time, and will have good recording characteristics. can be maintained.
出願人代理人 弁理士 鈴江武彦Applicant's agent: Patent attorney Takehiko Suzue
Claims (1)
スク基板において、上記樹脂層が熱硬化性のビニル基含
有シリコーン樹脂からなることを特徴とする光ディスク
基板。1. An optical disc substrate in which an uneven shape is transferred to a resin layer provided on a transparent substrate, wherein the resin layer is made of a thermosetting vinyl group-containing silicone resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63057692A JP2538972B2 (en) | 1988-03-11 | 1988-03-11 | Optical disc substrate manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63057692A JP2538972B2 (en) | 1988-03-11 | 1988-03-11 | Optical disc substrate manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01232552A true JPH01232552A (en) | 1989-09-18 |
| JP2538972B2 JP2538972B2 (en) | 1996-10-02 |
Family
ID=13062996
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63057692A Expired - Fee Related JP2538972B2 (en) | 1988-03-11 | 1988-03-11 | Optical disc substrate manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2538972B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04232629A (en) * | 1990-08-17 | 1992-08-20 | Internatl Business Mach Corp <Ibm> | Manufacture of grooved substrate and multilayer structure |
| US5242731A (en) * | 1990-03-29 | 1993-09-07 | Kabushiki Kaisha Toshiba | Resin composition for an optical disc and an optical disc using it |
| EP0668584B1 (en) * | 1994-02-21 | 2002-07-03 | OTB Group B.V. | Method of manufacture of a master disk or optical disk |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6414082A (en) * | 1987-07-08 | 1989-01-18 | Nippon Sheet Glass Co Ltd | Grooved substrate |
-
1988
- 1988-03-11 JP JP63057692A patent/JP2538972B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6414082A (en) * | 1987-07-08 | 1989-01-18 | Nippon Sheet Glass Co Ltd | Grooved substrate |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5242731A (en) * | 1990-03-29 | 1993-09-07 | Kabushiki Kaisha Toshiba | Resin composition for an optical disc and an optical disc using it |
| JPH04232629A (en) * | 1990-08-17 | 1992-08-20 | Internatl Business Mach Corp <Ibm> | Manufacture of grooved substrate and multilayer structure |
| EP0668584B1 (en) * | 1994-02-21 | 2002-07-03 | OTB Group B.V. | Method of manufacture of a master disk or optical disk |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2538972B2 (en) | 1996-10-02 |
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| LAPS | Cancellation because of no payment of annual fees |