JP2002100037A - Method and device for manufacturing floppy (registered trademark) disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a floppy disk which as a small curvature or deformation with high productivity. SOLUTION: In a vacuum chamber 11, the outer peripheral part of a floppy disk base 1 is fixed by a fixing means 2. The fixing means 2 where the floppy disk base 1 is fixed is transferred to a filming chamber 12 adjacent to the inside of the vacuum chamber 11, where a magnetic film is formed by sputtering on the floppy disk base 1. The floppy disk base having the magnetic film formed is then transferred into the vacuum chamber 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a high-density floppy disk used for recording information.

[0002]

2. Description of the Related Art A magnetic recording medium such as a magnetic tape, a floppy disk or a hard disk is generally manufactured by forming a magnetic layer and a protective layer on a non-magnetic support. In such a magnetic recording medium, a magnetic recording medium such as a vapor-deposited tape or a thin-film hard disk having a recording layer of a ferromagnetic metal thin film formed by a vacuum film forming method such as a sputtering method or a vapor deposition method has been put to practical use. In the magnetic recording medium as described above, high magnetic energy can be easily obtained, and smooth surface properties can be easily achieved by smoothing the surface of the non-magnetic substrate (support).
It has a small spacing loss, can obtain high electromagnetic conversion characteristics, and is suitable for high-density recording materials. In particular, a magnetic layer obtained by a sputtering method can increase the magnetic energy as compared with a magnetic layer obtained by a vapor deposition method, and thus is used for a medium requiring a high recording density such as a hard disk.

On the other hand, a floppy disk type magnetic recording medium has been widely used because of its excellent impact resistance and low cost as compared with a hard disk. Further, the present applicant has disclosed that a 3.5-inch floppy disk can be formed by using a lower magnetic layer formed on a substrate or a coating type magnetic recording medium in which a thin magnetic layer is formed on the lower magnetic layer by applying a magnetic paint. It offers media with a large capacity of over 200 MB.

[0004] However, the recording density of a floppy disk is still 1/10 or less of that of a high-performance hard disk. This is largely because although many attempts have been made to produce a magnetic film by a sputtering method like a hard disk, it has not yet been put to practical use.

There are various reasons for this. One of the major reasons is that it is difficult to manufacture a floppy disk with little warpage or deformation. To increase transfer speed, high-density floppy disks slide at a very low flying height in contact with or close to contact with the magnetic head while rotating at a high speed like a hard disk, but at this time, if the floppy disk It comes into strong contact with the head, and the sliding becomes unstable, leading to a decrease in running durability and reliability. Therefore, it is necessary to keep the surface deviation of the floppy disk to 50 μm or less.
Such run-out is strongly affected by the warpage of the floppy disk in a static state.
It is necessary to suppress the warpage to 1 mm or less in a state where the disk is punched into a 5-inch disk shape. This warpage may be caused by a difference in stress between the front and back surfaces of the magnetic recording medium during the manufacturing process of the magnetic recording medium, when the support itself is originally provided, and it is not easy to suppress surface runout.

[0006] Generally, a film forming apparatus used for manufacturing a hard disk or an optical disk includes an apparatus called a sheet type and an apparatus called a pass type. In a single-plate type film forming apparatus, a plurality of process chambers are provided independently of a main chamber by a shutter, and a disk is moved between the process chambers, and a film is formed in each chamber by baking or sputtering.
On the other hand, in a pass-through type film forming apparatus, a disk passes through a plurality of connected process chambers, and a film is formed by baking or sputtering during the passage.

In the case of a hard disk or an optical disk, since the disk is a rigid substrate, by holding a part of the disk, it is possible to transfer the film between process chambers without deforming the disk and form a film. But,
In the case of a floppy disk, since the disk is a flexible substrate, there is a problem that the disk is deformed at the time of film formation if only a part is fixed like a hard disk. Therefore, when manufacturing a floppy disk using such a single-plate or pass-through film forming apparatus,
As disclosed in Japanese Patent Application No. 11-303544,
It is necessary to simultaneously form the magnetic film and the base film to be formed by sputtering on both sides of the substrate, and to fix the support with a highly rigid frame so that the support is not distorted during the transfer between the process chambers and the film formation.

[0008]

SUMMARY OF THE INVENTION However, Japanese Patent Application No.
The method of attaching and detaching the frame around the entirety of the flexible support as described in No. 303544 is complicated and does not improve production. Further, it is conceivable that the frame for fixing the support is large, and the frame is worn due to collision or friction when fixing or detaching the frame to or from the transporting means.

In general, when a frame on which a support is mounted moves back and forth between vacuum and the atmosphere, sputter debris adhered to the frame is likely to be peeled off in the atmosphere under the influence of oxidation or the like, thereby causing contamination. There's a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a method of manufacturing a floppy disk with little warpage or deformation with high productivity using a sheet-type or pass-through type sputtering apparatus and a method used in such a method. It is intended to provide a device.

[0011]

According to a method of manufacturing a floppy disk of the present invention, an outer peripheral portion of a floppy disk support is fixed in a vacuum chamber by a fixing means, and the fixing means to which the floppy disk support is fixed is connected to the fixing means. Moving to a film forming chamber adjacent to the vacuum chamber, forming a magnetic film on the floppy disk support by sputtering in the film forming chamber, and moving the floppy disk support on which the magnetic film is formed into the vacuum chamber. It is characterized by the following.

An apparatus for manufacturing a floppy disk according to the present invention comprises: a vacuum chamber in which a floppy disk support can be taken in and out; a film forming chamber adjacent to the vacuum chamber for forming a magnetic film on the floppy disk support by a sputtering method; A fixing means for detachably fixing an outer periphery of the floppy disk support; and a conveying means for conveying the fixing means between the vacuum chamber and the film forming chamber. is there.

[0013] The sputtering method for forming the magnetic film on the floppy disk support may be any of a sheet type and a pass type.

The floppy disk support means a support having substantially the same size as the shape of the product floppy disk. For example, a donut shape having a hole such as a circle at the center, or a circular or polygonal shape. There is no particular limitation as long as the shape is used as a floppy disk.

If the vacuum chamber is adjacent to the film forming chamber,
It may be provided on one side of the film forming chamber or on both sides. That is, the vacuum chamber in which the outer peripheral portion of the floppy disk support is fixed by the fixing means and the vacuum chamber in which the floppy disk support moves after the magnetic film is formed may be the same or different. Good.

The film forming chamber is a chamber for forming a magnetic film,
This means a chamber for forming each layer such as a base film, a seed layer, a protective layer, and a lubricating layer, and a baking chamber before film formation is also included in the film forming chamber.

The fixing means is not particularly limited as long as it fixes the outer peripheral portion of the floppy disk support. Even if the fixing means fixes the entire outer peripheral portion, it fixes only a part. You may. In general, since the floppy disk support is a flexible substrate, it is preferable that the fixing means has a function of maintaining tension uniformly in the peripheral direction of the floppy disk support.

It is preferable that the fixing means comprises two peripheral jigs having a semicircular grip for gripping a peripheral portion of the floppy disk support.

[0019]

According to the method and apparatus for manufacturing a floppy disk of the present invention, since the outer peripheral portion of the floppy disk support is fixed in the vacuum chamber by the fixing means, it is possible to manufacture a floppy disk with less warpage and deformation. It is.

In the method and apparatus for manufacturing a floppy disk according to the present invention, the fixing means is moved to a film forming chamber adjacent to a vacuum chamber, and a magnetic film is formed on a floppy disk support in the film forming chamber by sputtering. Since the floppy disk support on which the magnetic film is formed is moved into the vacuum chamber, the fixing means and the transport means do not move in the atmosphere. For this reason, the sputter debris adhered to the fixing means and the transporting means are peeled off by the influence of oxidation and the like, so that they do not cause contamination and almost no minute dust in the air is brought into the film formation chamber. Thus, a floppy disk capable of achieving reliable reproduction can be manufactured.

According to the method and apparatus for manufacturing a floppy disk of the present invention, the floppy disk support has substantially the same shape as the product floppy disk, so that the floppy disk support can be fixed to or removed from the fixing means. When fixing or removing the fixing means to or from the transporting means, no spatters are peeled off from the fixing means due to collision or friction, so that contamination is not generated, and the fixing means is fixed to the floppy disk support. Since the outer periphery of the floppy disk can be detachably fixed, the step of attaching and detaching the floppy disk support to and from the fixing means is not troublesome, and productivity can be improved.

If the fixing means is a two-peripheral jig having a semicircular grip for gripping the peripheral portion of the floppy disk support, reliable reproduction with less warpage or deformation can be achieved. Floppy disks can be manufactured with higher productivity.

[0023]

Embodiments of the present invention will be described below in more detail with reference to the drawings. FIG. 1 is a schematic diagram of a floppy disk manufacturing apparatus according to the first embodiment of the present invention, which is a sheet-type sputtering method. FIG. 2 is a front view of a floppy disk support fixing means according to the first embodiment. 3 is a side view of FIG. 2, and FIG. 4 is a front view of a floppy disk support fixing means according to the second embodiment.

As shown in FIG. 1, a floppy disk manufacturing apparatus 10 according to the present invention includes a loading vacuum chamber 11 into which a floppy disk support 1 can be loaded from a loading port 15 and a loading vacuum chamber 11 adjacent to the loading vacuum chamber 11. Film forming chambers 12a, 12b, 12c, and 1 for forming a magnetic film and the like by sputtering.
2d; fixing means 2 for detachably fixing the support 1;
A transporting means 14 for transporting the fixing means 2 from the loading vacuum chamber 11 to the deposition chamber 12 according to the arrow to an unloading vacuum chamber 13, and an unloading vacuum chamber 13 capable of unloading the support 1 on which the magnetic film or the like is formed from the unloading port 16 And The number of process film forming chambers is not particularly limited, and a baking chamber or the like may be provided.

The support 1 is a floppy disk manufacturing apparatus 1
Until it is introduced to zero, it is temporarily stored in a stock case (not shown) provided with a gap. Manufacturing equipment 1
At the time of introduction into the storage case, the center hole of the support 1 is held from the stock case by an automatic transfer device or the like, and is carried in from the carry-in entrance 15, and is set in the fixing means 2 in the carry-in vacuum chamber 11.

As shown in FIG. 2 and FIG.
Has a support periphery fixing jig 6 for gripping a part of the outer periphery of the support 1 and a connection portion 5 for connecting the fixing means 2 to the transport means 14. The fixing jig 6 has a groove 3 slightly larger than the thickness of the support 1, and the support 1 can be fixed by inserting the outer peripheral portion of the support 1 into the groove 3.

The groove 3 is 2 μm to 300 μm thick, preferably 5 μm to 200 μm, more preferably 10 μm to 100 μm thicker than the thickness of the support 1 so that the support 1 can be easily attached and detached.
It is preferable to provide m wide. In order to make the insertion of the support 1 easier, a fixing jig 6 into which the support 1 is inserted is provided.
It is preferable that the insertion portion 4 is chamfered.
With such chamfering, the support 1 can be easily inserted into the groove 3 even if the support 1 has some warpage or vibration. Conversely, in order to prevent the support 1 once inserted from dropping from the fixing jig 6, the tip of the groove 3 is processed to be narrower than the thickness of the support 1,
It is preferable that the support 1 can be fixed with an appropriate holding force.

The support 1 fixed to the fixing means 2 in the loading vacuum chamber 11 is transferred by the transfer means 14 from the main film forming chamber 12 to the process film forming chamber 12a. In each of the process film forming chambers, as shown in FIG. 4, a fixing means 2 ′ having a semicircular support peripheral edge fixing jig 7 for gripping the peripheral portion of the support 1 is provided. Is preferably fixed by two semicircular fixing means 2 and 2 ′.

In FIG. 4, a fixing means 2 ′ is fixed via a chamber connecting portion 8 in each of the process film forming chambers 12 a, 12 b, 12 c, and 12 d, and the support 1 conveyed by the conveying means 14. It has the function of receiving and fixing this. The fixing jig 7 is provided with a groove similar to that of the fixing jig 6, and the outer peripheral portion of the support 1 is weakly fixed along the groove. In this state, a film is formed in the process film forming chamber 12a, and when one process is completed, the support 1 is separated from the fixing jig 7, and the conveying means 14 together with the fixing jig 6 of the fixing means 2 causes the next step. Process deposition chamber 1
2b. In this manner, a magnetic film, a base film, and the like are sequentially formed, and each process is performed. The floppy disk support 1 on which the film is formed in each of the process film forming chambers 12a, 12b, 12c, and 12d is moved to the unloading vacuum chamber 13 and removed from the fixing jig 6 in the reverse method of fixing the first support. And stored in a stock case.

In order to detach the support 1 from the fixing jig 7, the fixing jig 7 preferably has a smaller fixing force than the fixing jig 6. For this reason, the fixing jig 7
Is preferably wider than the groove width of the fixing jig 6.
Specifically, the groove width of the fixing jig 7 is 10 μm to 500 μm, more preferably 30 μm to 300 μm than the thickness of the support 1.
m, more preferably 50 μm to 200 μm. It is preferable that the depth of the groove of the fixing jig 7 be larger than the depth of the groove of the fixing jig 6. The fixing jig 7
It is not necessary to finely design the insertion portion into which the support 1 is inserted unlike the fixing jig 6.

Next, a case where the sputtering method of the floppy disk manufacturing apparatus is a continuous type will be described. FIG. 5 is a schematic diagram of a floppy disk manufacturing apparatus using a continuous sputtering method according to a second embodiment, and FIG. 6 is a schematic diagram of a transfer tray on which a plurality of floppy disks can be set.

As shown in FIG. 5, the floppy disk manufacturing apparatus 50 transfers the floppy disk support
Vacuum chamber 51 which can be loaded from above, a film forming chamber 52 which is adjacent to the loaded vacuum chamber 51 and forms a magnetic film or the like on a support by sputtering, and a transfer tray 57 which can set a plurality of supports.
Transport means 54 for transporting the transport tray 57 from the loading vacuum chamber 51 to the unloading vacuum chamber 53 via the film forming chamber 52, and the unloading vacuum chamber 53 capable of unloading the support on which the magnetic film is formed from the unloading port 56. It is what you have.

As in the case of the single-wafer sputtering method, the support is temporarily stored in a stock case or the like until it is introduced into the manufacturing apparatus 50. The center hole is held by an automatic transfer device or the like, and is carried in from the carry-in port 51, and the carry-in vacuum chamber 5
1 is set on the fixing means 60 in the transport tray 57. The transfer tray 57 on which the support is set is moved to the film forming chamber 52.
And a magnetic film or the like is formed by a sputtering method in each of the film forming chambers 52a, 52b, 52c, and 52d.
The support on which the film is formed is moved to the unloading vacuum chamber 53 while being set on the transfer tray 57, removed from the fixing means 6 in the transfer tray 57 in the unloading vacuum chamber 53, and stored in the stock case.

As shown in FIG. 6, the support 61 is fixed in the transfer tray 57 by fixing means 60. The fixing means 60 includes two support member peripheral jigs 66 having a semicircular grip portion for gripping the peripheral portion of the floppy disk support member 61.
And 67, and transfer tray connecting portions 62 and 63 fixed to the transfer tray, and the support 61 is fixed in the tray 57.

In order to manufacture a desired floppy disk, a process of baking, forming a base film, and forming a magnetic film is generally required. Further, if necessary, a process for forming a seed layer between the support and the underlayer, a protective layer on the magnetic film, and a lubricating layer on the protective layer is required.

The floppy disk stored in the stock case can be formed by forming each layer (for example, a protective layer or a lubricating layer) that has not been formed in the above steps, attaching a center core to a center hole, incorporating the shell into a shell, The process is shifted to the burnishing, servo writing, veri-faying process, and servo writing process.

As described above, the method and apparatus for manufacturing a floppy disk of the present invention are extremely excellent in productivity because a disk-shaped floppy disk support can be manufactured in the same process as a hard disk or an optical disk.
Furthermore, compared to the conventional technology in which the floppy disk support is fixed by a large frame, there is no need to attach or detach the frame, so there is no dust from the frame, and there are excellent advantages such as a reduced number of punching steps. .

Next, the details of the support and each film used for manufacturing the floppy disk of the present invention will be described. The material of the floppy disk support is preferably a heat-resistant resin film such as an aromatic polyimide film or an aromatic polyamide film. In the film forming step, the temperature of the support increases during the baking or sputtering process.If the heat resistance of the support is not sufficient, the support fixed with a weak force may exceed the softening point of the support. This is because there is a risk of deformation. The thickness of the support is preferably from 10 μm to 200 μm, more preferably from 20 μm to 150 μm, further preferably from 30 μm to 10 μm.
It is preferably 0 μm. If the thickness is too thin, the stability at the time of high-speed rotation is not enough, and the surface run-out increases.
If the thickness is too large, the rigidity at the time of rotation is high, resulting in insufficient reliability against impact at the time of contact and jumping of the recording head.

As in the case where the support itself has a large warp or deformation, a case where warpage occurs due to a difference in the coefficient of moisture expansion and thermal expansion between the front and back surfaces, and a case where the surface roughness of the front and back surfaces is different, If the support cannot be used as it is, it is preferable that two supports are laminated and used symmetrically. As the adhesive used at this time, it is preferable to use an adhesive sheet made of a thermosetting resin or a heat-resistant thermoplastic resin from the viewpoint of productivity and uniformity of thickness.

When the surface properties of the support are insufficient,
Before punching the floppy disk support into a predetermined shape, it is preferable to form an undercoat for smoothing on the surface of the heat-resistant resin film. Since the lower coating film is required to have the same heat resistance as the material of the support, it is necessary to use a heat-resistant resin such as a polyimide resin, a polyamide-imide resin, a silicone resin, and a fluorine-based resin. Cannot be used. Above all, it is preferable to use a thermosetting imide resin or a thermosetting silicone resin having a high smoothing effect as a material of the undercoat. The thickness of the undercoat is preferably 0.1 μm to 0.3 μm.

As the thermosetting imide resin, a polyimide resin which is a thermal polymer of an imide monomer having two or more terminal unsaturated groups in the molecule can be preferably exemplified.
Such an imide monomer includes, for example, the following chemical formula 1
And bisallylnadiimide represented by the formula:

[0042]

Embedded image Here, R ¹ and R ² each independently represent a hydrogen or methyl group, and R ³ represents a divalent linking group such as an aliphatic or aromatic hydrocarbon group. More specifically, R ³ is a linear or branched alkylene group and alkenyl group, a cycloalkylene group, a cycloalkylene group having an alkylene group, an aromatic group, an aromatic group having an alkylene group, a polyoxyalkylene group, a carbonyl group. And ether groups. The solvent solubility of the imide monomer and the heat resistance of the polyimide resin as a polymer thereof are mainly determined by the structure of R ³ . Therefore, desired characteristics can be achieved by appropriately selecting the structure of R ³ .

It is preferable that the thermosetting polyimide resin is not polyimide that has already been polymerized, but is polyimide that is prepared by applying an imide monomer to a heat-resistant resin film and thermally polymerizing the same. The imide monomer has already undergone the imide cyclization reaction and has two or more terminal unsaturated groups in the molecule. The polymerization reaction to polyimide proceeds by addition polymerization of a vinyl group by heating or the like. Since this polymerization reaction proceeds at a relatively low temperature, it can be provided on various non-magnetic supports. Further, since the imide monomer is dissolved in a general-purpose organic solvent due to its structure, it is excellent in productivity and workability. Furthermore, the viscosity of the solution is low because the imide monomer has a smaller molecular weight than the polyimide, and therefore, when it is applied on a non-magnetic support, the imide monomer has good wraparound to unevenness and a sufficiently high smoothing effect.

When such an imide ring and a terminal unsaturated bond are
Imide monomer compounds having at least one
No. 0662, JP-A-60-178882, JP-A-61
No. 18761, JP-A-63-170358, and JP-A-7-53516. Such compounds are commercially available from Maruzen Petrochemical as BANI series and ANI series.

In the undercoat, other components, such as a curing agent for accelerating polymerization, heat-resistant fine particles (filler) for forming irregularities on the surface, a coupling agent for improving adhesion, A rust preventive or the like for preventing oxidation of the film may be contained.

For example, as a curing agent, p-toluenesulfonic acid, p-xylenesulfonic acid, methyltoluenesulfonate, pyridinium p-toluenesulfonate, pyridinium m-nitrobenzenesulfonate, methylhydrazine sulfate and the like can be preferably used.

As a coating solvent for the undercoat film,
Although different depending on the type of R ³ , many structures can be dissolved in toluene, xylene, acetonitrile, cyclohexanone, methyl ethyl ketone, acetone, and the like, and some structures can be dissolved in isopropyl alcohol, ethanol, methanol, and the like. Note that these solvents may be used as a mixed solvent.

Preferred examples of the curable silicone resin include silicone resins prepared by a sol-gel method using a silicon compound into which an organic group has been introduced as a raw material. Such a silicon resin has a structure in which a part of the bond of silicon dioxide is substituted with an organic group, and is much more excellent in heat resistance than silicon rubber. In addition, since it is more flexible than a silicon dioxide film, cracking and peeling hardly occur even when the film is formed on a flexible film such as a heat-resistant resin film.

Since the monomer as a raw material is directly applied to the heat-resistant resin film by using a general-purpose solvent and cured, the wraparound to unevenness is good and the smoothing effect is high. Furthermore, since the condensation polymerization reaction proceeds at a relatively low temperature by the addition of a catalyst such as an acid or a chelating agent, curing can be performed in a short time, and production using a general-purpose coating machine is possible.

As a monomer which is a raw material of the thermosetting silicone resin, a silane coupling agent having an aromatic hydrocarbon group, an organic group containing an aliphatic group or an epoxy group, or the like is preferable. Aromatic hydrocarbon groups and aliphatic hydrocarbon groups have the effect of imparting flexibility to the cured resin, and silane coupling agents having aromatic hydrocarbon groups are more heat-resistant than those having aliphatic hydrocarbon groups. Is more preferable because it is excellent. The silane coupling agent containing an epoxy group has an effect of curing a coating film at a relatively low temperature.

Examples of the silane coupling agent containing an aromatic hydrocarbon group include those having a structure represented by the following chemical formula 2.

[0052]

Embedded image Here, R and R ′ are a monovalent organic group such as a methyl group, A is a divalent organic group such as an alkylene group or a benzene ring and Si.
May be directly connected (without A), B is a monovalent group such as an alkoxy group, a halogen, a hydroxyl group, and X + Y +
Z = 4.

A is preferably a direct bond between Si and a methylene group or a benzene ring (A is absent), and B is preferably an alkoxy group in consideration of reactivity and corrosiveness of the magnetic film. Is more preferably an alkoxy group having 4 or less carbon atoms such as a methoxy group. X is preferably 1 or 2, but is more preferably 1 in order to facilitate the polymerization reaction. Y is preferably 0 or 1, but is preferably 0 or 1 to facilitate the polymerization reaction.
Is more preferable. Therefore, Z is more preferably 3. In particular,

Embedded image

Embedded image And so on.

Examples of the silane coupling agent containing an organic group having an epoxy group include those having a structure represented by the following chemical formula 5.

[0055]

Embedded image Here, A is a divalent organic group such as an alkylene group, B is a monovalent organic group such as hydrogen or an alkyl group, R is a monovalent organic group such as an alkyl group, X is an alkoxy group, a hydroxyl group, a halogen, A monovalent group selected from hydrogen, L + M + N = 4
It is.

A is preferably hydrogen, and R is preferably a monovalent organic group such as a methyl group or an ethyl group. X is preferably an alkoxy group in consideration of reactivity and corrosiveness of the magnetic film, and more preferably an alkoxy group having 4 or less carbon atoms such as a methoxy group for facilitating a polymerization reaction. M is preferably 1 or 2, but is more preferably 1 for facilitating the polymerization reaction. L is preferably 0 or 1, but is more preferably 0 to facilitate the polymerization reaction. Therefore, N is more preferably 3. In particular,

Embedded image And so on. These compounds are disclosed in
1-111871 and JP-A-63-232224.

It is to be noted that a silane coupling agent containing a hydrocarbon group such as a methyl group may be mixed and used for heat resistance, cost reduction and polymerization rate adjustment. When a silane coupling agent containing a hydrocarbon is used in combination, the heat resistance of the undercoat film can be further improved. Examples of the silane coupling agent containing a hydrocarbon group include R-Si (OR ') ₃ . However, R and R 'are hydrocarbon groups. In addition, the heat resistance of a lower coating film can be improved more as the carbon number of R is smaller.

The above-mentioned silane coupling agent having an aromatic hydrocarbon group and alkoxysilane as a silane coupling agent containing an organic group having an epoxy group are hydrolyzed and polymerized by coating and drying according to the method described below to form siloxane. Create a bond. On the other hand, the epoxy group undergoes ring-opening polymerization by an acid catalyst or heat. The hydrolysis rate and the polymerization rate can be adjusted by adding an acid such as hydrochloric acid as needed.

In order to start the polymerization from a lower temperature,
It is preferable to use a curing agent in combination, for example, a metal chelate compound,
Various compounds such as organic acids and salts thereof, and perchlorates are known, but are preferably metal chelate compounds in order to prevent the corrosiveness of the magnetic film at a low curing temperature. For example, when aluminum acetylacetonate is added to 3-glycidoxypropyltrimethoxysilane as a curing catalyst, curing can be performed only by heating at about 100 ° C. for a short time. Therefore, using the gravure continuous coating method, the film can be wound without blocking. As such a curing agent, a chelate compound of a metal with a β-diketone such as aluminum acetylacetonate, zirconium acetylacetonate, or titanium acetylacetonate is particularly preferably used. The coating solvent used at this time is determined by the amount of hydrochloric acid added and the structure of the silane coupling agent, but ethanol, methanol, isopropyl alcohol, cyclohexanone and the like can be preferably used.

To prepare an undercoat layer comprising a thermosetting polyimide resin layer or a thermosetting silicone resin layer on a heat-resistant resin film, a monomer to which a curing agent or the like is added as necessary is dissolved in an organic solvent. This coating solution is applied to the wire bar method,
A method of applying the composition on a heat-resistant resin film by a gravure method, a spray method, a dip coating method, a spin coating method or the like and then drying the applied film can be used. Further, after that, if necessary, the undercoating film is baked to accelerate the curing, and the heat resistance, the solvent resistance, the adhesion and the like can be improved. Drying is performed to volatilize the solvent, but curing can be performed simultaneously at this time. As the drying method, hot air drying, infrared drying and the like which are generally performed can be used. The drying temperature at this time is preferably about 60C to 250C.

After the coating film is dried, as a firing method for further promoting the curing, hot air heating, infrared heating, hot roller heating and the like can be used. The heating temperature at this time is
Depending on the thickness of the coating film, the method of forming the magnetic film and the film forming temperature, if the thickness is about 1 μm, the temperature is 100 ° C. to 350 ° C.
C. is preferable, and more preferably 200 to 270C. If the temperature is lower than this, the progress of the polymerization reaction may be insufficient, or a residual gas or a decomposition gas may be generated during the sputtering of the magnetic film, which may hinder the crystal growth of the magnetic film. Conversely, if it is too high, the support may be deformed or productivity may be reduced. Some materials can be polymerized by ultraviolet irradiation, electron beam irradiation, or the like, in addition to polymerization by heating.

Further, by providing minute projections having a very low height on the surface of the undercoating film, the real contact area between the magnetic recording medium and the sliding member can be reduced and the sliding characteristics can be improved. It is preferable to provide a minute projection structure on the surface of the magnetic film of the substrate. This microprojection structure also has the effect of significantly improving the handleability of the support after bonding. As a method for producing such micro projections, a method of applying spherical silica particles dispersed in a solvent, a method of applying an emulsion to form organic projections, and the like can be used.However, in order to ensure heat resistance, Silica particles are more preferred. It is also possible to use a binder to fix the protrusions to the film surface, but it is preferable to use a resin having sufficient heat resistance to ensure heat resistance, and such a material is used as an adhesive. It is preferable to use a thermosetting imide resin or a thermosetting silicone resin.

The height of the microprojections is 5 nm to
60 nm is preferable, and 10 nm to 30 nm is more preferable. The density is preferably in the range of 0.1 pieces / μm ^{2 to} 100 pieces / μm ² , and more preferably in the range of 1 piece / μm ² to 10 / μm ² . The height and the density of the minute projections are both average values. If the height of the minute projections is too high, the electromagnetic conversion characteristics are degraded due to the spacing loss between the recording / reproducing head and the medium, while if too small, the effect of improving the sliding characteristics is reduced. On the other hand, if the density of the fine projections is too low, the effect of improving the sliding characteristics is reduced. Preferably, the thickness of the binder applied is 20 nm or less. If the coating thickness of the binder is too large, adhesion (blocking) to the film back surface may occur after drying.

The support of a floppy disk, particularly an aromatic polyamide or aromatic polyimide, has a high water absorption. If used as it is when forming a magnetic film, the moisture contained in the base is rapidly released at the same time as the heating, so that the magnetic properties are high. May be deteriorated. In such a case, it is effective to use a baking process before forming the magnetic film. The baking temperature is preferably higher than the magnetic film forming temperature, specifically, preferably about 150 ° C. to 400 ° C., and more preferably 200 ° C. to 300 ° C. Baking can be performed using heating means such as lamp heating and an infrared heater.

The ferromagnetic metal thin film serving as a magnetic layer is preferably formed by a sputtering method. As a sputtering method, a known method such as a DC magnetron sputtering method or an RF magnetron sputtering method can be used. As the composition of the magnetic layer, a metal or alloy mainly composed of cobalt or iron can be used. Specifically, Co-C
r, Co-Ni-Cr, Co-Cr-Ta, Co-Cr
-Pt, Co-Cr-Ta-Pt, Co-Cr-Pt-
Si, Co-Cr-Pt-B, Co-O, Fe-Pt and the like are preferable, and Co-Cr-Pt and Co-Cr-Pt-Ta are more preferable from the viewpoint of improving electromagnetic conversion characteristics. The thickness of the magnetic layer is preferably set to 10 nm to 30 nm.

In order to improve the magnetostatic properties of the magnetic layer, it is preferable to provide an underlayer. The composition of the underlayer may be a known metal or alloy such as Cr, V, T
i, Ta, W, Si or the like or an alloy thereof can be used, and particularly, Cr and Cr-Ti are more preferable. The thickness of the underlayer is preferably 5 nm to 100 nm,
More preferably, the thickness is 10 nm to 60 nm. In order to further control the crystal orientation of the underlayer, a seed layer is preferably used under the underlayer. The composition of the seed layer is Ta, Mo, W, V , Zr, Cr, Rh, H
f, Nb, Mn, Ni, Al, Ru, Ti or alloys thereof, more preferably Ta, Cr, Ti, Si or alloys thereof, and the thickness of the seed layer is 5 nm to 6 nm.
It is preferably set to 0 nm. Further, an adhesion layer may be provided to enhance the adhesion between the underlayer and the undercoating or the heat-resistant resin film. The composition of the adhesion layer may be Cr, V, T
It is preferable to use i, Ta, W, Si or the like or an alloy thereof.

When the magnetic layer is formed by the sputtering method, it is preferable to form the film while the support is heated. The higher the temperature, the higher the coercive force and the lower the noise of the floppy disk. . This heating is preferably performed in a baking process prior to the sputtering, and the sputtering process is preferably started before the substrate is cooled.

In order to improve the running durability and corrosion resistance of the floppy disk, it is preferable to provide a protective film and a lubricating film on the ferromagnetic metal thin film. As the material of the protective film, oxides such as silica, alumina, titania, zirconia, cobalt oxide and nickel oxide, titanium nitride, silicon nitride, nitrides such as boron nitride, silicon carbide, chromium carbide, carbides such as boron carbide, Carbon such as graphite and amorphous carbon is preferred. The protective film is more preferably a hard film having a hardness equal to or higher than that of the head material, and more preferably a film which hardly causes seizure during sliding, and its effect is stably maintained. As such a protective film, there is a hard carbon film called a DLC film (diamond-like carbon).

The DLC film is an amorphous carbon film formed by a plasma CVD method, a sputtering method, or the like, and is microscopically a mixture of clusters formed by sp ² bonds and clusters formed by sp ³ bonds. The DLC film preferably has a Vickers hardness of at least 1,000 kg / mm ² ,
More preferably, it is at least 000 kg / mm ² . D
When the structure of the LC film is measured by Raman spectroscopy,
The main peak, so-called G peak near 1540 cm ^-1 is detected shoulder called a D-peak 1390 cm ^-1, whereby it is possible to confirm.

These hard carbon films can be prepared by a sputtering method or a CVD method. However, from the viewpoint that productivity, stability of quality, and good abrasion resistance can be ensured even with an ultrathin film having a thickness of 10 nm or less. It is preferable to make it by a method. In particular, the chemical species generated by decomposing carbon-containing compounds such as alkane such as methane, ethane, propane and butane, or alkene such as ethylene and propylene, or acetylene such as acetylene by a plasma CVD method, It is preferable to apply a negative bias voltage to the mesh provided in front of the mesh and accelerate and deposit the mesh.

Further, nitrogen gas is mixed with the raw material gas,
By using a DLC composed of C, H, and N, the coefficient of friction with respect to the head can be reduced. When the thickness of the protective film is large, the electromagnetic conversion characteristics are deteriorated and the adhesion to the magnetic layer is reduced. When the thickness is small, the abrasion resistance is insufficient.
nm to 30 nm is preferable, and particularly preferably 5 nm to 20 nm.

As the lubricating film, a known hydrocarbon-based lubricant,
Fluorinated lubricants, extreme pressure additives and the like can be used. Examples of the hydrocarbon-based lubricant include carboxylic acids such as stearic acid and oleic acid, esters such as butyl stearate, sulfonic acids such as octadecylsulfonic acid, phosphoric esters such as monooctadecyl phosphate, stearyl alcohol, oleyl alcohol and the like. Alcohols, carboxylic acid amides such as stearamide, amines such as stearylamine, and the like.

Examples of the fluorine-based lubricant include lubricants in which part or all of the alkyl groups of the hydrocarbon-based lubricant are substituted with fluoroalkyl groups or perfluoropolyether groups. Examples of the perfluoropolyether group include a perfluoromethylene oxide polymer, a perfluoroethylene oxide polymer, a perfluoro-n-propylene oxide polymer (CF ₂ CF ₂ CF ₂ O) _n , and a perfluoroisopropylene oxide polymer (CF ( CF ₃ ) CF ₂ O)
_n or a copolymer thereof is preferred. Specifically, a perfluoromethylene-perfluoroethylene copolymer having a hydroxyl group at a molecular terminal (FOMBLIN Z-DO)
L) and the like.

Examples of extreme pressure additives include phosphoric esters such as trilauryl phosphate, phosphites such as trilauryl phosphite, thiophosphites and thiophosphoric esters such as trilauryl trithiophosphite, and the like. Preferred are sulfur-based extreme pressure agents such as dibenzyl sulfide.

The above lubricants can be used alone or in combination of two or more. As a method of applying these lubricants on the magnetic film or the protective film, the lubricant is dissolved in an organic solvent and applied by a wire bar method, a gravure method, a spin coating method, a dip coating method, or the like in a manufacturing apparatus. May be attached by a vacuum evaporation method using the evaporation process chamber provided in the above. The amount of lubricant applied is 1 mg / m
^{2 to} 30 mg / m ² is preferable, and 2 mg / m ^{2 to} 20 m
g / m ² is more preferred.

Examples of the rust preventive include nitrogen-containing heterocycles such as benzotriazole, benzimidazole, purine and pyrimidine, and derivatives having an alkyl side chain introduced into the mother nucleus thereof, benzothiazole, 2-mercaptone benzothiazole, Examples thereof include nitrogen and sulfur-containing heterocycles such as a seindene ring compound and a thiouracil compound, and derivatives thereof. The rust inhibitor may be used as a mixture with the lubricant, or may be used by applying it on the protective film. Before applying the lubricant, apply the rust inhibitor on the protective film and lubricate it An agent may be applied and used. The coating amount of rust preventives is more preferably preferably from ² to 10 mg / m ² about 0.1 mg / m, is 0.5mg / m ² ~5mg / m ² approximately.

Specific examples of the tetrazaindene ring compound usable for the above purpose include those having a structure represented by the following chemical formula 7.

[0078]

Embedded image Here, R is a hydrocarbon group selected from an alkyl group, an alkoxy group, and an alkylamide group, and particularly has 3 to 20 carbon atoms. In the case of an alkoxy group, R ⁴ OCOCH ₂
- (R ⁴ is _{C 3 H 7 -, C 6} H 13 -, phenyl), C ₆ H ₁₃ in the case of the alkyl group _{-, C 9 H 19 -,} C 17 H 35 -, in the case of an alkylamide group Is R ⁵ NHCOCH _2- (R ⁵
Is preferably phenyl, C ₃ H ₇ —).

Further, specific examples of the thiouracil ring compound include those having a structure represented by the following chemical formula 8.

[0080]

Embedded image However, R is selected from the same as those in the above tetrazaindene ring compound.

Hereinafter, examples will be described.

(Example) The maximum protrusion roughness Rmax of the magnetic surface is 80 nm, the average center line roughness Ra is 0, 7 nm, and the thickness is 25.
A heat-resistant resin film made of a μm aromatic polyamide was dried in an oven at 160 ° C. for 1 hour. The two aromatic polyamide films were bonded to each other with a roll laminator using a thermosetting adhesive sheet (00C02 manufactured by Sony Chemical Co., Ltd.) so that the magnetic surface was on the outside. The lamination temperature at this time was 120 ° C.

Next, a thermosetting imide resin (BANI manufactured by Maruzen Petrochemical Co., Ltd.) was applied on both sides of the support by dip coating.
-NB) in ethanol-cyclohexane and dried at room temperature, and then heated at 230 ° C for 30 minutes to obtain a thickness of 1.
An undercoat of 0 μm was prepared. Further, an ethanol-cyclohexane solution of silica particles having a diameter of 18 nm was applied on the undercoating film by a dip coating method, and then dried at 250 ° C. for 5 minutes. The average value of the projection height was about 20 nm, and the projection density was 10 pieces. / μm ² minute projections were formed. The film provided with the undercoat was punched into a 3.7-inch disk shape to prepare a floppy disk support.

Next, the floppy disk support is stored in a stock case, placed in a carry-in vacuum chamber of a sheet type sputtering apparatus, and the floppy disk support is taken out of the stock case and gripped by a fixing jig 6 shown in FIG. I let it.
The fixing jig 6 was transported to the main chamber, and a film was formed in each process chamber in which the fixing jig 7 was installed. The process chamber is a baking chamber at 230 ° C, 200 ° C
Baking chamber, Ar ion cleaning chamber, Ta-Si seed layer sputtering chamber, C
r-Ti undercoat sputter chamber, Co-Cr-Pt
The residence time of each process chamber was set to 10 seconds in the order of a magnetic film sputtering chamber, a 0 ° C. cleaning chamber, and a DLC protective film CVD chamber made of C, H, and N. The floppy disk on which the film formation was completed was stored again in the stock case and taken out to the atmosphere through the preliminary exhaust chamber.

Subsequently, a center core was attached to a floppy disk, and a perfluoropolyether-based lubricant (Fusion made by Ausimont Co., Ltd.) was applied on the protective films on both sides by dip coating.
OMBLIN Z-DOL) was applied with a solution of a fluorine-based solvent (FC-77 manufactured by Sumitomo 3M) to form a lubricating film having a thickness of 1 nm. This floppy disk was incorporated into a Zip100 cartridge manufactured by Fuji Photo Film Co., Ltd. to prepare a floppy disk medium.

The prepared floppy disk had no warpage or deformation and had a good appearance. When the runout at 3000 rpm was evaluated by an optical fiber displacement meter, the inner circumference was 20 μm and the outer circumference was 40 μm, and the rotation stability was good. 130kFCI using MR head on inner circumference
Was recorded and reproduced, the output modulation in one round was small, and the C / N was 35 dB. Furthermore, a fixed track (inner circumference) continuous running durability test was performed in a Zip100 drive under an environment of 23 ° C. and 50% RH. The output decreased by 0.8 dB even after running for 300 hours, indicating good durability. Was.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a floppy disk manufacturing apparatus according to a first embodiment of the present invention, which is formed by a sheet-type sputtering method.

FIG. 2 is a front view of a floppy disk support fixing means according to the first embodiment;

FIG. 3 is a sectional view of the floppy disk support fixing means shown in FIG. 2;

FIG. 4 is a front view of a floppy disk support fixing means according to a second embodiment;

FIG. 5 is a schematic diagram of a floppy disk manufacturing apparatus according to a continuous sputtering method according to a second embodiment.

FIG. 6 is a schematic diagram of a transport tray on which a plurality of floppy disks can be set.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Floppy disk support 2 Fixing means 10 Floppy disk manufacturing apparatus 11 Loading vacuum chamber 12 Deposition chamber 13 Unloading vacuum chamber 14 Transport means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Shin Nagao, Inventor 2-12-1, Ogimachi, Odawara-shi, Kanagawa Prefecture Inside Fuji Photo Film Co., Ltd. (72) Inventor Junji Nakata 2-12-1, Ogimachi, Odawara-shi, Kanagawa Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 5D112 AA02 AA24 FA04 FB21 FB25

Claims (4)

[Claims] 1. An outer peripheral portion of a floppy disk support is fixed in a vacuum chamber by fixing means, and the fixing means to which the floppy disk support is fixed is moved to a film forming chamber adjacent to the vacuum chamber. A method of manufacturing a floppy disk, comprising: forming a magnetic film on the floppy disk support in a film chamber by a sputtering method; and moving the floppy disk support on which the magnetic film is formed into a vacuum chamber. 2. The fixing device according to claim 2, wherein the fixing means has a semicircular grip for gripping a peripheral edge of the floppy disk support.
2. A support jig comprising two supporting members.
A method for manufacturing the floppy disk according to the above. 3. A vacuum chamber in which a floppy disk support can be taken in and out, a film forming chamber adjacent to the vacuum chamber for forming a magnetic film on the floppy disk support by sputtering, and an outer periphery of the floppy disk support. An apparatus for manufacturing a floppy disk, comprising: fixing means for detachably fixing; and conveying means for conveying the fixing means between the vacuum chamber and the film forming chamber. 4. A fixing device according to claim 2, wherein said fixing means has a semicircular grip for gripping a peripheral edge of said floppy disk support.
4. A support jig comprising two peripheral jigs.
An apparatus for manufacturing a floppy disk according to the above.