JP2001028174A - Damping material and head suspension using the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent static electricity from being charged without disturbing the characteristics of a spring of a head suspension, to be excellent in punching workability in a production process, and to suppress production cost and reduce weight. It is intended to provide a vibration damping material that does not cause a head damage. A constraining body layer made of a plastic film is provided.
Is a vibration damping material 4 in which an antistatic treatment of static electricity is performed by forming an antistatic layer 7 on the layer surface, and the constraining body layer 5 and the viscoelastic body layer 6 are laminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a damping material adhered to a head suspension of a recording disk device and a head suspension using the same.

[0002]

2. Description of the Related Art In a recording disk device such as a hard disk drive or a magneto-optical disk drive for rotating a recording disk, a head unit for reading and writing information includes:
Generally, as shown in FIG. 3A, the head 1 includes a head 1 such as a magnetic head and an optical head, and a head suspension 2 that receives the head. Reference numeral 3 denotes a mounting block for fixing the head suspension.

The head section receives vibrations from a rotating disk, a driving device for the head 1, a motor for rotating the disk, and the like, whereby a head suspension 2 formed of a leaf spring or the like is formed. Deformed,
The position of the head 1 is shifted, and a reading error or a writing error is likely to occur.

Therefore, in order to reduce or eliminate the vibration in the head suspension 2, as shown in FIG. 3B, a vibration damping material 4 formed by laminating a restraining body layer and a viscoelastic body layer is used.
Is attached to the head suspension 2 (Japanese Patent Publication No. 4-8868). According to this method, the viscoelastic body layer sandwiched between the vibrating head suspension 2 and the restraining body layer deforms with the vibration deformation of the head suspension 2 to generate an internal resistance (molecular friction), and the vibration energy Is converted into heat energy, so that a vibration damping effect that the vibration energy directly received by the head suspension 2 is greatly reduced is obtained.

[0005] In order to enhance the above-mentioned vibration damping effect, it is important that the rigidity of the constraining body layer is high.
A metal plate such as stainless steel is used. As the viscoelastic body layer, an adhesive, rubber, or the like is used.

[0006]

However, a damping material having a metal restraining member layer is excellent in damping characteristics,
Since the rigidity is high, the characteristics of the head suspension 2 as a spring may be impaired. Also, the constraining body layer needs to be punched in order to have a shape corresponding to the shape of the head suspension 2. However, since the punching process causes sagging and burrs peculiar to metal on the processed end surface, a fine There is a problem that it is difficult to perform punching. Another problem is that the weight of the constraining body layer is heavy, making it difficult to reduce the weight. Further, there is a problem that the material cost is increased.

[0007] In order to solve such a problem, for example, a plastic film is used for the restraining body layer because it is possible to perform fine punching without disturbing the characteristics of the head suspension 2 as a spring. Damping materials have been proposed.

[0008] However, this does not occur in the metal constraining layer, but when a plastic film is used as the constraining layer, the plastic film usually has the property of an insulator, so that there is an inconvenience of being charged. . Therefore, if the plastic film as the constraining layer is a damping material that is used without any antistatic treatment, for example, when the damping material 4 is peeled from the separator, static electricity is generated on the constraining body layer. If the damping material 4 is adhered to the head suspension 2 in that state, the head 1 may be damaged.

[0009] Also, carbon,
A method is also conceivable in which a plastic film is made conductive or semiconductive by kneading and mixing a conductive filler such as a metal (oxide) to eliminate the charge of the constraining body layer. At this time, the conductive filler may fall off the cut surface. Therefore, if the damping material 4 is attached to the head suspension 2 in this state, the dropped conductive filler may damage the head 1. It could be.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and eliminates electrostatic charging without impairing the characteristics of a spring of a head suspension, and has excellent punching workability in a production process. In addition, it is an object of the present invention to provide a vibration damping material which suppresses the production cost and reduces the weight, does not cause any damage to the head, and a head suspension using the same.

[0011]

In order to achieve the above object, the present invention relates to a vibration damping material which is used by being adhered to a head suspension of a recording disk device, comprising a restraining member layer made of a plastic film. A first gist of the present invention is a vibration damper made of a laminate in which a viscoelastic body layer is laminated and having a layer surface of the constraining body layer subjected to an antistatic treatment of static electricity. A second aspect of the present invention is a head suspension of a recording disk device, wherein the head suspension has the damping material adhered to at least a part thereof.

The present inventors have solved the problem of electrification without impairing the spring properties of the head suspension, have excellent punching workability in the production process, and have reduced production costs and reduced weight. We worked diligently to obtain a damping material that would not cause the head to be damaged. In this process, the damping material using a plastic film for the restraint layer does not impair the spring properties of the head suspension, excels in punching workability, reduces production costs, and reduces weight. It is very effective to use a plastic film for this purpose, and it was noted that if this plastic film is subjected to a specific antistatic treatment that does not cause damage to the head, the disadvantages of using a plastic film are eliminated. Therefore, as a result of various studies, it has been found that the above-mentioned problem can be solved by using a vibration damping material in which the layer surface of the constraining body layer has been subjected to an antistatic treatment of static electricity, and has reached the present invention. Here, the “layer surface of the constraint layer” refers to both the front surface and the back surface of the constraint layer.

That is, the vibration damping material of the present invention does not knead and mix conductive fillers such as carbon and metal (oxide) into the plastic film used for the constraining body layer. It has been found that there is no inconvenience such as the conductive filler falling off from the cut surface during the punching process of the plastic film, and the above-mentioned problem can be solved.

In particular, when the antistatic treatment is applied to the contact surface of the constraining body layer with the viscoelastic body layer, static electricity (peeling electrification) generated when the damping material is peeled from the separator is prevented. The present inventors have found that the above-mentioned problems can be solved more favorably because the effect can be expected to be higher and the antistatic layer can be prevented from external influences such as scratches and oxidation at the time of contact.

Further, when the antistatic treatment is performed by forming an antistatic layer by vapor deposition of a metal,
Since the surface is made of metal, there is an effect that the surface resistance is extremely low. Further, when the antistatic layer is formed by coating a conductive plastic, the antistatic layer can be formed relatively easily, and since it is transparent or translucent, there is an effect that there is little change in hue. For this reason, it has been found that the above-mentioned problem can be solved even more favorably.

The above plastic has an elastic modulus of 4.9.
When it is a polyimide film of × 10 ⁹ N / m ² or more,
It has been found that they are relatively inexpensive and have excellent vibration damping characteristics.

A head suspension of a recording disk device having the vibration damping material adhered to at least a part thereof has a desired shape such as workability, reduction of production cost, weight reduction and antistatic treatment. It has been found that the head suspension can prevent reading and writing errors more effectively because the vibration material is attached.

[0018]

Next, an embodiment of the present invention will be described.

The vibration damping material of the present invention is obtained by integrally laminating a constraining body layer made of a plastic film and a viscoelastic body layer made of an adhesive. Further, an antistatic treatment of static electricity is performed on the layer surface of the constraining body layer, and specifically, an antistatic layer is formed.

Next, an embodiment of the vibration damping material of the present invention will be described. FIG. 1 is a cross-sectional view of the vibration damping material 4 in which the antistatic layer 7 is formed on the contact surface of the constraining body layer 5 with the viscoelastic body layer 6. On the outer surface of the viscoelastic material layer 6, the separator 8 is temporarily attached in a laminated manner because the adhesiveness of the viscoelastic body layer may hinder the storage and transportation of the vibration damping material 4 before it is attached. When the damping material 4 is attached to the head suspension of the recording disk device, the separator 8 is peeled off and used. As shown in FIG. 1, the antistatic layer 7 is
Formed on the surface in contact with the viscoelastic body layer 6 can more effectively prevent static electricity (peeling charge) generated when the vibration damping material 4 is peeled off from the separator 8, and the antistatic layer 7 can be avoided from external influences such as scratches and oxidation at the time of contact.

Next, another embodiment of the vibration damping material of the present invention will be described. As shown in FIG. 2, this damping material 4 ′ has an antistatic layer 7 formed on the outer surface of the constraining body layer 5. Other configurations are the same as those in FIG. 1, and the same portions are denoted by the same reference numerals. The use form of the damping material 4 'shown in FIG. 2 is the same as that of the damping material 4 shown in FIG. This damping material 4 ′ also eliminates static electricity charging without impairing the characteristics of the head suspension as a spring,
In addition, the punching workability in the production process is excellent, the production cost is reduced, the weight is reduced, and the cause of damaging the head does not occur.

The vibration damping material of the present invention is not limited to the form in which the antistatic layer 7 is formed on one of the constraining body layers 5 as shown in FIGS. Even if the prevention layer 7 is formed on both surfaces of the constraining body layer 5, the viscoelastic body layer 6 is formed to have a multilayer structure in which a plurality of the constraining body layers 5 and the antistatic layer 7 are laminated on one surface. It may be.

As a method of forming the antistatic layer 7 by the antistatic treatment of the constraining body layer 5, for example, a method of depositing a metal such as aluminum or chromium, or a conductive plastic such as polyaniline or polypyrrole is used. Coating methods and the like can be mentioned. Above all, the above-described method of depositing a metal has an effect of suppressing the surface resistance to be low, and thus is preferable. In particular, it is more preferable to use aluminum for vapor deposition of a metal because it is excellent in cost. Further, the above-described method of coating a plastic having conductivity has an effect that it can be formed relatively easily, and is preferable. In particular, it is more preferable to use polypyrrole for the conductive plastic because the surface resistance can be reduced.

The antistatic layer 7 is formed on the layer surface of the constraining body layer 5 by these various methods. The thickness of the antistatic layer 7 is not particularly limited, and the surface resistance, charge amount, and half-life of the obtained vibration damping material are set so as to achieve the desired reference values of the present invention. However, the thickness is usually set to about 100 to 5000 ° for metal deposition and to about 0.01 to 5 μm for conductive plastic. Detailed measurement methods and reference values of surface resistance, charge amount, and half-life will be described in the following examples.

Although the thickness of the plastic film of the constraining body layer 5 is not particularly limited, it is usually 5 to 2 mm.
It is preferable to set it to 00 μm. That is, if the thickness is less than 5 μm, the effect as a constraining body tends to be poor, and if it exceeds 200 μm, there tends to be a tendency to impair the characteristics of the head suspension as a spring.

Although the plastic film is not particularly limited, the higher the elastic modulus is, the more excellent the vibration damping property is. Therefore, the elastic modulus is 2.9 × 10 ⁹ N / m ^2.
It is preferable to use the above. And as the plastic film, for example, polyimide resin,
Examples include biaxially oriented polyethylene terephthalate (PET), biaxially oriented polypropylene, and aramid resin. Above all, a polyimide film having an elastic modulus of 4.9 × 10 ⁹ N / m ² or more is more preferable because it has excellent vibration damping properties and is relatively inexpensive.

The material for forming the viscoelastic layer 6 is not particularly limited, but it is generally preferable to use an acrylic pressure-sensitive adhesive excellent in vibration damping characteristics and heat resistance. For example, in the case of a hard disk drive, the internal temperature during operation of the device may reach 50 to 60 ° C.
This is because a material having insufficient heat resistance such as a butyl-based adhesive may be thermally deformed. A silicone-based pressure-sensitive adhesive is known as a heat-resistant pressure-sensitive adhesive. However, in a hard disk or the like, the recording surface is contaminated, which may lead to reading / writing errors or damage to the head.

Examples of the acrylic pressure-sensitive adhesive include those obtained by the method disclosed in Japanese Patent Application Laid-Open No. 5-132658. In this method, a photopolymerization initiator and a crosslinking agent are mixed with an acrylic acid alkyl ester monomer and a monomer having a carboxyl group, and the mixture is irradiated with ultraviolet rays to obtain a tape-shaped adhesive.
As the acrylic acid alkyl ester monomer, one having an alkyl group having 8 to 12 carbon atoms is usually used.

If the viscoelastic layer 6 other than the silicone-based pressure-sensitive adhesive is used without reducing the generation of organic gas, the same disadvantages as described above such as contamination of the recording surface of a hard disk or the like cannot be avoided. When there is a possibility that an organic gas is generated, it is necessary to reduce the amount of the organic gas from the viscoelastic layer 6 by various methods. As these methods, for example, a pressure-sensitive adhesive which is a material of the viscoelastic body layer 6 is applied to one surface of the constraining body layer 5, cured, and then passed through a drying tower at a temperature higher than usual, and a coating solvent is applied. And a method of evaporating unreacted components. Further, after the punching process is performed, the obtained vibration damping material may be vacuum-dried to reduce an organic gas such as a coating solvent.

The thickness of the viscoelastic layer 6 formed from the pressure-sensitive adhesive obtained by the above method is not particularly limited, but is usually preferably set to 10 to 250 μm. That is, when the thickness is less than 10 μm, the vibration damping effect tends to be poor, and when the thickness is more than 250 μm,
This is because there is a tendency to impair the characteristics of the head suspension as a spring.

The viscoelastic layer 6 is not limited to a single-layer structure as shown in FIGS. 1 and 2, but may have a structure in which a plurality of viscoelastic sheets are laminated. When the viscoelastic layer 6 has poor adhesion to the recording disk device, an adhesive layer may be formed on the outer surface of the viscoelastic layer 6. In this case, it is necessary to use a non-silicone adhesive as a material for forming the adhesive layer.

In general, a silicone-based release agent is often applied to the separator 8, but as described above, the recording surface of a hard disk or the like may be contaminated, leading to read / write errors or damage to the head. In the present invention, it is more preferable to use a release treatment agent containing no silicone. Examples of the release treatment agent include a long-chain alkyl type, an alkyl fluoride type and the like.

The vibration damping material of the present invention can be obtained, for example, as follows. That is, the constraining body layer in which the antistatic layer is formed by the above-described various antistatic treatments on at least one layer surface, and the viscoelastic body layer are positioned so as to face each other and laminated and integrated by an appropriate method. Obtainable. More specifically, there are a method in which the two are passed through a pair of rubber rolls and pressure-bonded, and a method in which both are laminated and pressed by a press. Further, there is a method of forming a viscoelastic body layer by directly applying a pressure-sensitive adhesive to one surface of the constraining body layer and drying it.

On the other hand, a separator such as a PET film is prepared, and a dilute solution of the non-silicone release agent is applied to the temporary attachment surface of the separator with respect to the viscoelastic material layer by a known method. By drying in such a manner as above, a separator having the above-mentioned temporarily attached surface subjected to a release treatment is produced. And the above-mentioned separator is stuck on the outer surface of the above-mentioned viscoelastic body layer by a publicly known method, and the damping material of the present invention in which the separator is temporarily laminated is obtained. In addition,
When the damping material is used, the separator is peeled off from the outer surface of the viscoelastic layer and used.

The vibration damping material obtained in this manner has the same vibration damping characteristics as those of the vibration damping material using the metal restraining body layer. In addition, not only is the weight light and the material cost is low, but also there is an advantage that burrs are not easily generated in fine punching. Since the antistatic treatment is performed without damaging the head of the recording disk device, the defect of the plastic film restraining member layer is eliminated.

Then, for example, using the above-mentioned damping material 4 (4 '), utilizing the adhesive action of the viscoelastic body layer 6 of this damping material 4 (4'), it is shown in FIG. As described above, by adhering the damping material 4 (4 ') to the center surface of the head suspension 2 via the viscoelastic layer 6, an excellent reading and writing error by the head 1 can be effectively prevented. Head suspension 2 can be obtained. The vibration damping material 4 (4 ') is not only stuck to the center surface of the head suspension 2 as described above, but is also stuck to an appropriate surface such as the left and right side surfaces and the back surface. You can wear it. When attaching the vibration damping material 4 (4 ′) to the head suspension 2, as described above, in addition to using the adhesive action of the viscoelastic body layer 6, the vibration damping material 4 (4 ′) is used. '), A new adhesive layer may be formed on one side, and the damping material 4 (4') may be attached to the head suspension 2 via this adhesive layer. As the adhesive layer forming material,
There is no particular limitation, and various types of conventionally known adhesives can be used. For example, the adhesive is appropriately selected according to the material of the head suspension 2 to be bonded.

Next, examples will be described together with comparative examples.

[0038]

Example 1 A 50 μm-thick polyimide film (UPILEX 50S, manufactured by Ube Industries, Ltd .: elastic modulus 6.4 × 10
⁹ N / m ² ) on one side under the following conditions
An aluminum anti-static layer was formed by performing an aluminum vapor deposition process so that the aluminum layer of Å was formed. Next, the surface of the polyimide film on which the antistatic layer was formed and a viscoelastic layer made of an acrylic pressure-sensitive adhesive having a thickness of 125 μm were passed between opposed rubber rolls to obtain a laminated sheet. Then, the obtained laminated sheet was punched into a 2 mm square by a high-speed press to obtain a target vibration damping material.

[Aluminum vapor deposition treatment] Aluminum is heated to 1220 ° C. under reduced pressure of 1.33 Pa or less to evaporate the aluminum film, and the polyimide film is placed in this atmosphere. Formed.

[0040]

Example 2 Soluble polyaniline was coated on one side of a 50 μm-thick PET film (Lumirror S10, manufactured by Toray Industries, Ltd .; elasticity: 3.9 × 10 ⁹ N / m ² ), dried, and dried to a thickness of 0.1 μm.
A 1 μm antistatic layer is formed, and then the antistatic layer forming surface of the PET film and a 125 μm thick viscoelastic material layer made of an acrylic pressure-sensitive adhesive are passed between opposed rubber rolls. A laminated sheet was obtained. Then, the intended damping material was obtained from the obtained laminated sheet in the same process as in Example 1.

[0041]

EXAMPLE 3 A laminated sheet was laminated by passing a surface of a polyimide film opposite to a surface on which an antistatic layer was formed and a viscoelastic layer made of an acrylic pressure-sensitive adhesive through a pair of opposed rubber rolls. Obtained. Other setting conditions are the same as in the first embodiment. Then, the intended damping material was obtained from the obtained laminated sheet in the same process as in Example 1.

[0042]

Example 4 A laminated sheet was laminated by passing a surface of a PET film opposite to a surface on which an antistatic layer was formed and a viscoelastic layer made of an acrylic pressure-sensitive adhesive through a pair of opposed rubber rolls. Obtained. Other setting conditions are the same as in the second embodiment. Then, the intended damping material was obtained from the obtained laminated sheet in the same process as in Example 1.

[0043]

Comparative Example 1 A 50 μm-thick polyimide film which had not been subjected to any surface treatment such as formation of an antistatic layer was used as a constraining body layer. Otherwise, the target vibration damping material was obtained under the same setting conditions and steps as in Example 1.

[0044]

Comparative Example 2 A 25 μm thick stainless steel plate SUS304 which had not been subjected to any surface treatment such as formation of an antistatic layer was used as a constraining body layer. Except for this, the target vibration damping material was obtained under the same setting conditions and steps as in Example 1.

With respect to the thus obtained examples and comparative examples, the burr height, surface resistance, charge amount, half-life and vibration damping characteristics generated by punching were measured by the following method. The results were evaluated and the results are shown in Table 1 below.

[Burr height generated by punching] 2 mm
The acrylic adhesive was removed from the sample (vibration damping material) punched into the corner, and the thickness of the punched surface of the constraining body layer was measured with a dial gauge. Then, the difference from the thickness of the constraining body layer before punching was calculated and defined as the burr height. When the thickness was 10 μm or less, the punching property was determined to be good.

[Surface Resistance] The surface resistance of the constraining body layer was measured using a Hirester (MCP-HT250, manufactured by Mitsubishi Chemical Corporation) and a Loresta (MCP-T250, manufactured by Mitsubishi Chemical Corporation). The measurable upper limit was 1 × 10 ¹⁴ Ω / □, and when it exceeded, the measurement limit was exceeded, and it was marked as> 1 × 10 ¹⁴ Ω / □. Good characteristics were obtained at 1 × 10 ¹⁰ Ω / □ or less.

[Amount of Charge, Half-Life] The amount of charge on the surface of the viscoelastic layer was measured with an honest meter (S-5109, manufactured by Shishido Electro Co., Ltd.) with the constraining body layer and the viscoelastic layer bonded together. The charge amount at a charged voltage of 10 kV and the time until the charge amount was reduced by half were measured. The case where the half life was 60 seconds or less was regarded as good.

[Vibration Suppression Characteristics] A sample (damping material) was adhered to a base material (stainless steel plate, SUS304) having a thickness of 50 μm.
The loss coefficient was measured using an FT analyzer (CF-5220, manufactured by Ono Sokki Co., Ltd.). Specifically, the measurement temperature 25
The loss coefficient was determined by the half-width method using the above apparatus set to give a vibration of 3 ° C. and a frequency of 3 kHz. If the loss coefficient is 0.1 or more, the device has practical vibration damping characteristics and is considered to be good.

[Comprehensive Evaluation] A comprehensive evaluation was made according to the following criteria. ◎: All of the above characteristics satisfy the reference value and each of the characteristics is particularly excellent. ：: All of the above characteristics satisfy the reference value. Δ: One of the above characteristics does not satisfy the reference value.

[0051]

[Table 1]

From the above Table 1, it can be seen that the products of the examples obtained by subjecting the layer surface of the plastic film as the constraining body layer to a specific antistatic treatment have a small burr height, surface resistance, charge amount and half-life. As a result of the measurement, it was found that the vibration damping material was low in static charge and excellent in vibration damping characteristics. In contrast, Comparative Example 1 in which no antistatic treatment was performed on the layer surface of the constraining body layer
Although the burr height of the product was small, the measurement results of the surface resistance, the amount of charge, and the half-life showed that the product was more easily charged with static electricity than the other examples and the comparative examples. Also,
Comparative Example 2 using a stainless steel plate as the restraint layer,
Although it was found from the measurement results that the vibration damping characteristics were excellent and the electrostatic charge was small, the burr height was extremely large and the workability was poor.

[0053]

As described above, the vibration damping material of the present invention comprises a laminate in which a constraining layer made of a plastic film and a viscoelastic layer are laminated, and the layer surface of the constraining layer is prevented from being charged with static electricity. Processing has been applied. That is, since a plastic film having an antistatic treatment applied to at least one layer surface of the constraining member layer is used, a vibration damping material using a plastic film having no antistatic treatment applied to the constraining member layer is used. In comparison, static electricity is not charged to the constraining body layer, and as a result, there is no problem of damaging the head.

Further, since a plastic film is used as the constraining body layer, there is an advantage that burrs are not easily generated in the punching process. And the above damping material
By adhering to at least a part of the head suspension, the vibration received by the head suspension can be greatly reduced or eliminated, and errors in reading and writing by the head can be effectively prevented.

In particular, when the antistatic treatment is performed on the contact surface of the constraining body layer with the viscoelastic body layer, static electricity (peeling electrification) generated when the damping material is peeled from the separator is prevented. The effect is further improved, and the antistatic layer can be avoided from external influences such as scratches and oxidation at the time of contact.

Further, when the antistatic treatment is performed by forming an antistatic layer by vapor deposition of a metal,
Since the surface is made of metal, there is an effect that the surface resistance is extremely low. Further, when the antistatic layer is formed by coating of a conductive plastic, the antistatic layer can be formed relatively easily, and since it is transparent or translucent, the effect of little change in hue is exhibited, which is even better. A suitable damping material can be obtained.

The above plastic has an elastic modulus of 4.9.
When it is a polyimide film of × 10 ⁹ N / m ² or more,
This has the effect of being relatively inexpensive and having excellent vibration damping characteristics.

Therefore, the vibration damping material of the present invention does not impair the characteristics of the head suspension as a spring.
Elimination of static charge, excellent punching workability in the production process, suppression of production cost, reduction in weight, and no cause of damage to the head.

The head suspension of a recording disk device having the above-mentioned vibration damping material adhered to at least a part thereof has been developed to solve the above-mentioned problems such as workability, reduction of production cost, weight reduction and antistatic treatment. Since the vibration material is adhered, the head suspension can more effectively prevent reading and writing errors.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a vibration damping material of the present invention.

FIG. 2 is a sectional view showing another embodiment of the vibration damping material of the present invention.

FIG. 3A shows a conventional head suspension,
FIG. 3B is a plan view showing a state in which a damping material is attached to the head suspension.

[Explanation of symbols]

 5 Constraint layer 6 Viscoelastic layer 7 Antistatic layer

Continued on the front page (72) Inventor Yasuo Mito 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 3J048 AA06 AC01 AC05 AD05 BD08 BE06 EA13 5D059 AA01 BA01 CA21 CA26 DA33 EA07

Claims (6)

[Claims] 1. A damping material which is used by being adhered to a head suspension of a recording disk device, wherein said damping material comprises a laminate in which a restraining body layer made of a plastic film and a viscoelastic body layer are laminated. A vibration damping material characterized in that a layer surface of the layer is subjected to an antistatic treatment of static electricity. 2. The vibration damping material according to claim 1, wherein the antistatic treatment is applied to a contact surface of the constraint layer with the viscoelastic layer. 3. The vibration damping material according to claim 1, wherein the antistatic treatment is performed by forming an antistatic layer by vapor deposition of a metal. 4. The vibration damping material according to claim 1, wherein the antistatic treatment is performed by forming an antistatic layer by coating a conductive plastic. 5. The method according to claim 1, wherein the plastic has an elastic modulus of 4.9 × 1.
0 ⁹ N / m ² or more damping material according to claim 1 consisting of a polyimide film. 6. A head suspension of a recording disk device, wherein the vibration damping material according to claim 1 is adhered to at least a part of the head suspension. suspension.