JP2590304B2 - Information recording disk - Google Patents
Information recording diskInfo
- Publication number
- JP2590304B2 JP2590304B2 JP60054135A JP5413585A JP2590304B2 JP 2590304 B2 JP2590304 B2 JP 2590304B2 JP 60054135 A JP60054135 A JP 60054135A JP 5413585 A JP5413585 A JP 5413585A JP 2590304 B2 JP2590304 B2 JP 2590304B2
- Authority
- JP
- Japan
- Prior art keywords
- disk
- spacer
- information recording
- recording disk
- disk substrate
- 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.)
- Expired - Fee Related
Links
- 125000006850 spacer group Chemical group 0.000 claims description 38
- 239000000758 substrate Substances 0.000 claims description 38
- 230000002093 peripheral effect Effects 0.000 claims description 16
- 239000012790 adhesive layer Substances 0.000 claims description 8
- 239000010410 layer Substances 0.000 claims description 7
- 238000009423 ventilation Methods 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000000428 dust Substances 0.000 description 5
- 239000003822 epoxy resin Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000004925 Acrylic resin Substances 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 2
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229920005668 polycarbonate resin Polymers 0.000 description 2
- 239000004431 polycarbonate resin Substances 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000002990 reinforced plastic Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
Landscapes
- Optical Record Carriers And Manufacture Thereof (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は情報を記録し、又は記録した情報を再生する
情報記録用デイスクに係り、特に気圧変動によるデイス
ク基板などの変形を防止することができる情報記録用デ
イスクに関するものである。Description: BACKGROUND OF THE INVENTION The present invention relates to an information recording disk for recording information or reproducing the recorded information, and in particular, to preventing deformation of a disk substrate or the like due to atmospheric pressure fluctuation. The present invention relates to a possible information recording disk.
情報記録用デイスクは一般に記録容量が大きいために
一枚のデイスクに対する使用頻度が高く、記録再生装置
のスピンドルとの係合で内周スペーサの耐久性、耐磨耗
性が問題になる。In general, information recording disks have a large recording capacity and are frequently used for one disk. The engagement with the spindle of the recording / reproducing apparatus causes a problem in durability and abrasion resistance of the inner peripheral spacer.
そこで内周スペーサとデイスク基板を別部材で製作
し、内周スペーサは使用頻度に耐えられる耐磨耗性、耐
久性に優れた材料で作られている。Therefore, the inner peripheral spacer and the disk substrate are manufactured by separate members, and the inner peripheral spacer is made of a material having excellent wear resistance and durability that can withstand the frequency of use.
第３図は、従来の情報記録用デイスクの断面図であ
る。同図において１はステンレスなどの金属、強化プラ
スチツクなどの耐磨耗性、耐久性に優れた材料で形成さ
れた内周スペーサ、2,3は内側に記録層4,5を有するデイ
スク基板で、このデイスク基板2,3はアクリル樹脂、ポ
リカーボネート樹脂、塩化ビニル樹脂、エポキシ樹脂、
ガラスなどの透明体で構成されている。６は外周スペー
サ、７はエアギヤツプである。FIG. 3 is a sectional view of a conventional information recording disk. In FIG. 1, reference numeral 1 denotes an inner peripheral spacer formed of a metal such as stainless steel, a material having excellent wear resistance and durability such as reinforced plastic, and reference numerals 2 and 3 denote disk substrates having recording layers 4 and 5 on the inside. The disk substrates 2 and 3 are made of acrylic resin, polycarbonate resin, vinyl chloride resin, epoxy resin,
It is composed of a transparent body such as glass. Reference numeral 6 denotes an outer peripheral spacer, and reference numeral 7 denotes an air gap.
この様な構造において、デイスク基板2,3と内周スペ
ーサ１の接面、デイスク基板2,3と外周スペーサ６の接
面は紫外線硬化樹脂、エポキシ樹脂、超音波融着、レー
ザ融着などによつて一体に接着される。In such a structure, the contact surfaces of the disk substrates 2, 3 and the inner peripheral spacer 1 and the contact surfaces of the disk substrates 2, 3 and the outer peripheral spacer 6 are made of ultraviolet curable resin, epoxy resin, ultrasonic fusion, laser fusion, or the like. Are bonded together.
ところが、この種の情報記録用デイスクは内部がほぼ
完全密閉式であるため、飛行機などによる輸送中、ある
いは高度の高い地域での使用時などの様に大気圧の変動
によつて、エアギヤツプ７内の内圧と大気の外圧とに圧
力差が生じ、この圧力差によつてデイスク基板2,3など
に反りや変形が生じてオートフオーカス、トラツキング
などの光学系へ支障をきたす欠点があつた。However, since the information recording disk of this type is almost completely closed, the air gap in the air gap 7 may be affected by fluctuations in the atmospheric pressure, such as during transportation by airplane or when used in high altitude areas. A pressure difference is generated between the internal pressure and the external pressure of the atmosphere, and the pressure difference causes warpage and deformation of the disk substrates 2, 3 and the like, which has a drawback that an optical system such as an auto-focus or tracking is hindered.
特にデイスク基板2,3がアクリル樹脂、ポリカーボネ
ート樹脂、塩化ビニル樹脂、エポキシ樹脂などのプラス
チツク製の場合には、ガラスに比べてその反りや変形が
数倍大きく、そのために記録層4,5へクラツクが生じる
欠点があつた。In particular, when the disk substrates 2 and 3 are made of plastic such as acrylic resin, polycarbonate resin, vinyl chloride resin, and epoxy resin, the warpage and deformation are several times larger than that of glass, so that the recording layers 4 and 5 are cracked. There is a disadvantage that occurs.
このような欠点を解消するため、実開昭58−105042号
公報（従来技術１）、実開昭55−11613号公報（従来技
術２）ならびに実開昭57−149535号公報（従来技術３）
に記載されているような情報記録用デイスクがそれぞれ
提案されている。In order to solve such disadvantages, Japanese Utility Model Laid-Open No. 58-100502 (Prior Art 1), Japanese Utility Model Laid-Open No. 55-11613 (Prior Art 2) and Japanese Utility Model Laid-Open No. 57-149535 (Prior Art 3) have been proposed.
Have been proposed, respectively.
前記従来技術１の情報記録用デイスクは、デイスク基
板の厚さ方向に通気孔を形成し、その通気孔を外側から
プラグなどで塞ぐ構造になつている。The information recording disk of the prior art 1 has a structure in which a ventilation hole is formed in the thickness direction of the disk substrate, and the ventilation hole is closed from outside with a plug or the like.
前記従来技術２の情報記録用デイスクは、同じように
デイスク基板の厚さ方向に通気孔を形成し、その通気孔
をデイスク基板の内側からフイルタで覆う構造になつて
いる。Similarly, the information recording disk of the prior art 2 has a structure in which a ventilation hole is formed in the thickness direction of the disk substrate, and the ventilation hole is covered with a filter from the inside of the disk substrate.
前記従来技術３の情報記録用デイスクは、内周スペー
サあるいは外周スペーサのいずれか一方において、スペ
ーサの厚さ方向の中間位置に通気孔を形成したり、ある
いはスペーサのデイスク基板と接する表面に溝状の連通
孔を形成した構造である。The information recording disk according to the prior art 3 has a ventilation hole formed at an intermediate position in the thickness direction of the spacer in one of the inner peripheral spacer and the outer peripheral spacer, or has a groove-like shape on the surface of the spacer in contact with the disk substrate. This is a structure in which a communication hole is formed.
ところが前記従来技術１の情報記録用デイスクの場
合、通気孔がプラグで塞がれて密閉状態になっている
と、従来と同じように気圧変動によつてデイスク基板が
反ることがある。このようなことが起こらないようにす
るためには、時々プラグを外してデイスク内部を通気す
る必要があり、そのためにメンテナンスが煩雑になるば
かりでなく、通気後のプラグの装着を忘れたり、プラグ
が紛失することがある。However, in the case of the information recording disk according to the prior art 1, if the vent hole is closed by a plug and is in a hermetically sealed state, the disk substrate may warp due to atmospheric pressure fluctuation as in the related art. In order to prevent this from happening, it is necessary to remove the plug from time to time and ventilate the inside of the disk, which not only complicates maintenance, but also makes it difficult to forget to attach the plug after ventilation, May be lost.
また前記従来技術２の情報記録用デイスクの場合、通
気孔にフイルタを貼着する作業が必要であり、フイルタ
が外れるとそれがデイスク内部で動いて記録層に損傷を
与え、情報の記録再生に悪影響を及ぼす。In the case of the information recording disk of the prior art 2, it is necessary to attach a filter to the air hole, and when the filter comes off, it moves inside the disk and damages the recording layer, which makes it difficult to record and reproduce information. Adversely affect.
またこれら従来技術１、２の情報記録用デイスクと
も、通気孔の開口がデイスク基板の厚さ方向、すなわち
記録用デイスクを置いた状態で垂直方向に孔が形成され
ている。そのため前記プラグやフイルタが外れた状態で
記録用デイスクを放置していると、埃や水などが記録用
デイスクの上に落ちたとき通気孔を通つて直接デイスク
内に入り、情報の記録再生に悪影響を及ぼす危険性があ
る。In each of the information recording disks of the prior arts 1 and 2, the opening of the ventilation hole is formed in the thickness direction of the disk substrate, that is, in the vertical direction with the recording disk placed. Therefore, if the recording disk is left with the plug or filter removed, if dust or water falls on the recording disk, the dust or water directly enters the disk through the air holes, and is used for recording and reproducing information. Risk of adverse effects.
さらに前記従来技術３の情報記録用デイスクの場合、
実際のスペーサの厚さは0.5mm程度の極く薄いものであ
るから、その薄いスペーサの厚さ方向の中間位置に透孔
を形成することは非常に困難であり、歩留りが悪く、生
産コストが高くつく。Further, in the case of the information recording disk of the prior art 3,
Since the actual spacer thickness is as thin as about 0.5 mm, it is very difficult to form a through hole at the middle position in the thickness direction of the thin spacer, resulting in low yield and low production cost. Expensive.
また、スペーサの表面に溝を形成する方法において
も、前述のようにスペーサは極薄であるため射出成形に
よつて形成することは難しいから、薄いシート状の素材
をリング状に打抜いてスペーサを作り、その表面に溝を
切削加工などによつて形成する手段がとられる。しかし
この方法においてもスペーサは極薄であるから切削工程
での取り扱い、溝の形成が難しく、そのために歩留りが
悪く、作業効率が低いなどの欠点を有している。Also, in the method of forming a groove on the surface of the spacer, it is difficult to form the groove by injection molding because the spacer is extremely thin as described above. And a means for forming a groove on the surface by cutting or the like. However, even in this method, since the spacer is extremely thin, it is difficult to handle and form a groove in a cutting process, and therefore has a drawback such as low yield and low work efficiency.
そのためスペーサを厚くして、孔や溝を形成し易くす
ることも考えられるが、そうすると情報記録用デイスク
のトータルの厚さが厚くなり、薄形化や軽量化に障害に
なるとともに、大きく形成された通気孔を通つて埃や水
の進入が生じ易くなる。Therefore, it is conceivable to increase the thickness of the spacer to facilitate the formation of holes and grooves.However, doing so increases the total thickness of the information recording disk, which hinders thinning and weight reduction, and increases the size of the disk. Dust and water easily enter through the vent holes.
本発明の目的は、このような従来技術１〜３が有して
いる欠点を解消し、簡単な構造で埃や水などが直接デイ
スク内に入る危険性が非常に少なく、しかも生産効率の
良い情報記録用デイスクを提供するものである。An object of the present invention is to eliminate the drawbacks of the prior arts 1 to 3, and to reduce the risk of dust or water directly entering the disk with a simple structure, and to improve the production efficiency. This is to provide an information recording disk.
この目的を達成するため、本発明は、 内面に記録層を有するデイスク基板同志を間に内周ス
ペーサと外周スペーサを配置して一体に接着するととも
に、デイスク基板間のエアギヤツプと大気を通気孔で連
通した情報記録用デイスクにおいて、前記通気孔を、内
周スペーサとデイスク基板、外周スペーサとデイスク基
板の少なくとも一方の接着剤層中に形成された空洞によ
つて構成して、前記エアギヤツプと大気をその空洞で連
通したことを特徴とするものである。In order to achieve this object, the present invention provides a disk substrate having a recording layer on the inner surface, an inner spacer and an outer spacer arranged therebetween and integrally bonded together, and an air gap between the disk substrates and the atmosphere is provided by a vent. In the communicating information recording disk, the air hole is formed by a cavity formed in an adhesive layer of at least one of an inner spacer and a disk substrate, and an outer spacer and a disk substrate, and the air gap and the atmosphere are formed. It is characterized by communicating with the cavity.
次に本発明の実施例について図面とともに説明する。 Next, embodiments of the present invention will be described with reference to the drawings.
第１図は実施例に係る情報記録用デイスクの上側のデ
イスク基板を貼着する前の状態を示す平面図、第２図は
デイスク基板を貼着した後の第１図VIII−VIII線上の横
断面図である。FIG. 1 is a plan view showing a state before the disk substrate on the upper side of the information recording disk according to the embodiment is attached, and FIG. 2 is a cross-section taken along the line VIII-VIII of FIG. 1 after the disk substrate is attached. FIG.
内面に記録層4,5を有するデイスク基板2,3同志を間に
内周スペーサ１と外周スペーサ６を配置して一体に接着
して、デイスク基板2,3間にエアギヤツプ７を形成する
情報記録用デイスクの全体的な構造は、第３図に示した
従来のものと同様であるので重複する説明は省略する。Information recording for forming an air gap 7 between the disk substrates 2 and 3 by disposing the disk substrates 2 and 3 having the recording layers 4 and 5 on the inner surface and integrally bonding the inner and outer spacers 1 and 6 therebetween. The overall structure of the disk is the same as that of the conventional disk shown in FIG.
第１図、第２図において10は内周スペーサ１および外
周スペーサ６の表面に0.01mlずつ円周方向に沿つてスポ
ツト状に塗布した接着剤、11は第２図に示すように内周
スペーサ１および外周スペーサ６を介してデイスク基板
2,3を貼り合わせた時に形成される接着剤層、12はその
接着剤層11中に形成された空洞で、これによつてデイス
ク基板2,3とスペーサ1,6の間にデイスク基板2,3の径方
向に開口した通気孔８が形成される。1 and 2, reference numeral 10 denotes an adhesive applied to the surface of the inner peripheral spacer 1 and the outer peripheral spacer 6 in the form of a spot along the circumferential direction by 0.01 ml, and 11 denotes an inner peripheral spacer as shown in FIG. 1 and a disk substrate via the outer spacer 6
The adhesive layer 12 formed when the substrates 2 and 3 are bonded to each other is a cavity formed in the adhesive layer 11, whereby the disk substrate 2 is located between the disk substrates 2 and 3 and the spacers 1 and 6. , 3 are formed in the radial direction.
なお、空洞12は内周スペーサ１あるいは外周スペーサ
６の何れか一方に形成してもよい。The cavity 12 may be formed in either the inner spacer 1 or the outer spacer 6.
本発明者の実験によれば、前記実施例の情報記録用デ
イスクを1.5kg/cm2から0.5kg/cm2の圧力変動のサイクル
を10000回繰り返しても、デイスク基板2,3の反りなどの
変形が全く発生しないことが確認された。According to the experiment of the present inventor, even if the information recording disk of the above-described embodiment is subjected to a pressure fluctuation cycle of 1.5 kg / cm 2 to 0.5 kg / cm 2 10,000 times, even if the disk substrates 2 and 3 are warped. It was confirmed that no deformation occurred.
本発明は前述したように、デイスク基板間のエアギヤ
ツプと大気を連通させる通気孔の開口がデイスク基板の
径方向を向いているため、すなわち情報記録用デイスク
の内周面あるいは（ならびに）外周面に開口が形成され
ているため、情報記録用デイスクの放置中に埃や水など
が落ちても直接デイスク内部に入ることはほとんどな
く、前記従来技術1,2で提案されたようなプラグやフイ
ルタは不要である。As described above, according to the present invention, since the opening of the air gap between the disc substrates and the air hole for communicating the atmosphere is oriented in the radial direction of the disc substrate, that is, on the inner peripheral surface and / or outer peripheral surface of the information recording disk. Since the opening is formed, even if dust or water falls while the information recording disk is left, it hardly enters the disk directly, and the plugs and filters as proposed in the prior arts 1 and 2 are not used. Not required.
また本発明はスペーサとデイスク基板を接着する接着
剤層中の空洞によつて通気孔を構成するのであるから、
前記従来技術３のように極薄のスペーサに孔や溝を形成
する必要がなく、歩留りが高く、生産効率の向上が図れ
る。Further, in the present invention, since the air holes are formed by the cavities in the adhesive layer for bonding the spacer and the disk substrate,
There is no need to form holes or grooves in an ultra-thin spacer as in the above-described prior art 3, so that the yield is high and the production efficiency can be improved.
スペーサとデイスク基板はある一定の圧力をかけて接
着するため、接着剤層の厚さは極薄いものとなり、従つ
て接着剤層中の空洞（通気孔）も極薄に形成されるか
ら、埃や水の進入防止に効果的であり、通気孔の機能を
十分に果たし、信頼性の高い情報記録用デイスクを提供
することができる。Since the spacer and the disk substrate are bonded by applying a certain pressure, the thickness of the adhesive layer is extremely thin, and accordingly, the cavities (vents) in the adhesive layer are also formed extremely thin. It is effective in preventing the entry of water and water, sufficiently fulfills the function of a vent, and can provide a highly reliable information recording disk.
第１図は本発明の実施例に係る情報記録用デイスクの上
側のデイスク基板を貼着する前の状態を示す平面図、第
２図はデイスク基板を貼着した後の第１図VIII−VIII線
上の横断面図、第３図は従来の情報記録用デイスクの断
面図である。 １……内周スペーサ、2,3……デイスク基板、4,5……記
録層、６……外周スペーサ、７……エアギヤツプ、８…
…通気孔、10……接着剤、11……接着剤層、12……空
洞。FIG. 1 is a plan view showing a state before the disc substrate on the upper side of the information recording disc according to the embodiment of the present invention is attached, and FIG. 2 is a plan view after attaching the disc substrate. FIG. 3 is a cross-sectional view of a conventional information recording disk. 1 inner spacer, 2,3 disk substrate, 4,5 recording layer, 6 outer spacer, 7 air gap, 8
... vent holes, 10 ... adhesive, 11 ... adhesive layer, 12 ... cavities.
Claims (1)
間に内周スペーサと外周スペーサを配置して一体に接着
するとともに、デイスク基板間のエアギヤツプと大気を
通気孔で連通した情報記録用デイスクにおいて、前記通
気孔を、内周スペーサとデイスク基板、外周スペーサと
デイスク基板の少なくとも一方の接着剤層中に形成され
た空洞によつて構成して、前記エアギヤツプと大気をそ
の空洞で連通したことを特徴とする情報記録用デイス
ク。An information recording disk in which a disk substrate having a recording layer on its inner surface is provided with an inner peripheral spacer and an outer peripheral spacer disposed therebetween and adhered together, and an air gap between the disk substrates and the atmosphere are communicated by a vent hole. Wherein the air hole is constituted by a cavity formed in an adhesive layer of at least one of the inner spacer and the disk substrate, and the outer spacer and the disk substrate, and the air gap communicates with the atmosphere through the cavity. An information recording disk characterized by the following.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60054135A JP2590304B2 (en) | 1985-03-20 | 1985-03-20 | Information recording disk |
| US06/840,863 US4720826A (en) | 1985-03-20 | 1986-03-18 | Ventilation arrangement for use in an optical recording disc |
| EP19860400577 EP0195720B1 (en) | 1985-03-20 | 1986-03-19 | Ventilation arrangement for use in an optical recording disc |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60054135A JP2590304B2 (en) | 1985-03-20 | 1985-03-20 | Information recording disk |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61214157A JPS61214157A (en) | 1986-09-24 |
| JP2590304B2 true JP2590304B2 (en) | 1997-03-12 |
Family
ID=12962132
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60054135A Expired - Fee Related JP2590304B2 (en) | 1985-03-20 | 1985-03-20 | Information recording disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2590304B2 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5511613U (en) * | 1978-06-30 | 1980-01-25 | ||
| JPS58105042U (en) * | 1982-01-13 | 1983-07-16 | 富士通株式会社 | recoding media |
-
1985
- 1985-03-20 JP JP60054135A patent/JP2590304B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61214157A (en) | 1986-09-24 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |