JP3242553B2 - Buffer material for manufacturing optical disc, and tray using this buffer material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cushioning material suitable for manufacturing an optical disk having a metal layer such as aluminum, such as a video disk and an audio disk.

[0002]

2. Description of the Related Art Conventionally, audio discs (hereinafter, referred to as audio discs)
As shown in FIG. 1, for example, as shown in FIG. 1, a substrate layer 1 made of a polycarbonate resin, a vapor deposition layer 2 of a metal such as aluminum on the substrate layer, and ultraviolet curing to protect the aluminum vapor deposition layer 2 And a protective layer 3 made of resin. Usually, this CD is printed on the surface of the protective layer 3 by screen printing or offset printing 4 on the surface of the protective layer 3 while being placed on a cushioning material on a tray. In addition, since the toner is charged by friction between a screen or a roll and the protective layer 3 and the electrostatic charge easily accumulates on the vapor deposition layer 2, printing is performed from a tray to a CD.
When taking out, there was a problem that a spark discharge was generated toward the metal part of the printing press, and a pinhole was generated in the protective layer 3 of the CD. Therefore, as a buffer material on a tray used when printing a CD, an attempt was made to remove static charges by using a nonwoven fabric treated with antistatic treatment with a surfactant or a nonwoven fabric using acrylonitrile-copper sulfide composite fiber. However, the former cushioning material has poor static elimination performance, while the latter cushioning material has CD
This causes a new problem of damaging the base material layer 1, and none of them is suitable for practical use.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and in the production of an optical disk having a metal layer, particularly when printing, a spark discharge occurs or the optical disk has a problem. An object of the present invention is to provide a shock-absorbing material that does not damage and a tray using the shock-absorbing material.

[0004]

According to the present invention, a buffer material for manufacturing an optical disk (hereinafter simply referred to as a "buffer material") comprises a fiber sheet coated with an electronic conjugated polymer and a conductive resin sheet.
The tray of the present invention uses this cushioning material.

[0005]

The cushioning material of the present invention comprises a fiber sheet coated with an electron conjugated polymer and a conductive resin sheet laminated and integrated.
However , since the electron conjugated polymer has conductivity, the electrostatic charge can be released through the tray on which the buffer material is placed, and the electrostatic charge can be discharged by corona discharge when the optical disk is taken out of the tray. , It is possible to prevent spark discharge which is likely to occur when the optical disk is taken out of the tray. Further, since the electronic conjugated polymer is flexible, the cushioning material of the present invention does not damage the optical disk. Furthermore, conductive resin sheets are laminated and integrated.
Cushioning material with higher cushioning properties
You.

The electron conjugated polymer of the present invention includes, for example, acetylene, benzene, aniline, phenylacetylene, pyrrole, furan, thiophene, indole, and polymers obtained by polymerizing derivatives of these electron conjugated monomers. Among these, polypyrrole is particularly preferably used because it is excellent in conductivity and excellent in static elimination.

Although the cushioning material of the present invention includes a fiber sheet coated with an electron conjugated polymer, it may be formed by forming a fiber sheet and then coating it with an electron conjugated polymer, or forming a fiber sheet. The fiber sheet may be formed before the coating, that is, after the fibers, yarns, fiber webs and the like are coated with the electronic conjugated polymer. The former method was coated with an electron conjugated polymer without damaging the electron conjugated polymer
It is more preferable since a fiber sheet can be formed. Hereinafter, the former method will be described.

[0008] The fiber sheet coated with the electron conjugated polymer includes, for example, woven fabric, knitted fabric, and nonwoven fabric. Among them, the nonwoven fabric is bulky and can form a material having excellent cushioning properties. In this case, the ink can be easily transferred, so that it can be suitably used.
Hereinafter, the nonwoven fabric will be described.

[0009] As a fiber that can be used in the nonwoven fabric, for example,
Natural fibers such as silk, wool, cotton, hemp, asbestos, regenerated fibers such as rayon fibers, semi-synthetic fibers such as acetate fibers, polyamide fibers, polyvinyl alcohol fibers, acrylic fibers, polyester fibers, polyvinylidene chloride fibers, and polyvinyl chloride Synthetic fibers such as system fibers, polyurethane fibers, polyethylene fibers, and polypropylene fibers can be used.
A core-sheath type composite fiber composed of two or more resin components is a suitable fiber because the nonwoven fabric strength can be improved by fusing the sheath component.

The electron conjugated poly constituting the buffer material of the present invention
The fiber sheet coated with the polymer has a fiber diameter of 10 so that the electrostatic charge can be easily removed by corona discharge.
Ultra-fine fiber of less than or equal to 8 μm, more preferably less than or equal to 8 μm (preferably at least 0.1 μm in diameter for superior fiber strength)
Alternatively, a fiber having an irregular cross-sectional shape, preferably a pointed end is used. When the fiber diameter is 10 μm or less, there is also a feature that the nonwoven fabric is flexible and the optical disc is hardly damaged. The fiber having a fiber diameter of 10 μm or less can be obtained, for example, by a method generally called a melt blow method, or a conjugate fiber which can be divided into ultrafine fibers having a fiber diameter of 10 μm or less by mechanical and / or chemical treatment. (Hereinafter referred to as “splitable fibers”). Since the latter splittable fiber can be a short fiber, there are many fiber ends, and the cross-sectional shape of the ultrafine fiber obtained by splitting can have a pointed end, and is more excellent in corona discharge property. Therefore, it can be suitably used. The fiber diameter of the fiber having an irregular cross-sectional shape refers to a value converted into a circular cross section.

As the splittable fiber, as shown in FIG. 2, a sea-island type fiber having a cross section in which another component B is arranged in an island shape in one component A, and one component A as shown in FIG. And another component B are alternately laminated in a layered manner, or a multiple bimetallic fiber having a cross section, or as shown in FIG.
There is a chrysanthemum flower-shaped fiber having a cross section obtained by dividing into two or more by another component B extending radially from around the fiber axis. Among these, the cross section of the ultrafine fiber obtained by dividing the multi-bimetal type fiber or the chrysanthemum flower type fiber has a pointed portion, and corona discharge is more likely to occur. As a combination of the resin components constituting the splittable fiber, for example, when it is composed of two resin components, a polyamide resin and a polyester resin, a polyamide resin and a polyolefin resin, a polyester resin and a polyolefin resin, a polyester resin And different resins such as polyacrylonitrile resins, and similar resins such as polyethylene and polypropylene.

[0012] Such ultra-fine fibers and fibers having an irregular cross-sectional shape are used in a non-woven fabric so as to have excellent corona discharge properties.
It is preferably contained in an amount of at least 40% by weight, more preferably at least 40% by weight, and most preferably at least 60% by weight.

[0013] Highly crimped fibers can be suitably used because they have excellent cushioning properties. The term "highly crimped fiber" refers to a fiber having a number of crimps of 15 to 100 pieces / inch in a state where the crimps have become apparent. For example, a spiral crimp made of two or more kinds of resins having different shrinkage rates. And a fiber having a specific heat history and crimped by a single component. Among them, the former composite fiber is more preferably used because it has better cushioning properties. More specifically, a side-by-side type composite fiber composed of a high-melting polyester and a low-melting polyester can be suitably used because it has many spiral crimps and exhibits excellent cushioning properties.

In the present invention, a nonwoven fabric is formed by using the above-mentioned fibers. First, a fiber web is formed. As a method of forming the fiber web, for example, there are a dry method such as a card method and an air-lay method, a wet method, and a direct method such as a spun bond method and a melt blow method. The fiber webs obtained by these methods may be used alone or two or more may be laminated. For example, if one fiber web contains splittable fibers and the other fiber web contains highly crimped fibers, a nonwoven fabric having better static elimination properties and cushioning properties can be obtained.

Next, the fiber web is entangled by applying an external force such as a water flow or a needle, bonded with a binder, fused using the fusibility of the fibers constituting the fiber web, or fused. These are combined to form a nonwoven fabric.
Among them, when entangled by applying an external force such as a water flow or a needle, the fibers are easily arranged in the thickness direction of the nonwoven fabric, so that not only the cushioning property is excellent, but also the constituent fibers are short fibers, Since the fiber has a large number of ends and is more excellent in corona discharge property, it is a suitable nonwoven fabric forming method. In particular, since the entanglement method using a water stream can be entangled more densely, a nonwoven fabric having excellent rebound resilience can be obtained, and the ink can be more easily applied during printing. Further, when the above-mentioned mechanically dividable splittable fiber is used, the splittable fiber can be split at the same time as being entangled by a water stream, which is preferable in production.

Next, the nonwoven fabric is covered with an electron conjugated polymer.
Although the whole nonwoven fabric may be completely covered or partially covered, the surface resistance is 1 × 10 ⁹ Ω / □ or less, more preferably 1 × 10 ⁹ Ω / □, in order to obtain excellent static elimination. 10 ⁶ Ω
/ □ or less, most preferably 1 × 10 ⁴ Ω / □ or less. As a coating method using an electron conjugated polymer, for example, a method is used in which a solution containing an oxidizing agent such as iron (III) chloride or copper (II) chloride is applied to a nonwoven fabric and then polymerized by contact with the above-mentioned monomer. , Iron chloride (II
There is a method in which a polymer matrix containing an oxidizing agent such as I) and copper (II) chloride is adhered to a nonwoven fabric, and then the polymer is brought into contact with the above-mentioned monomer to polymerize. In addition, the method of contacting the nonwoven fabric with the monomer may be, for example, when the monomer is in a liquid state, impregnating, applying, or spraying the monomer on the nonwoven fabric to which the oxidizing agent is attached. What is necessary is just to place the nonwoven fabric to which the oxidizing agent has adhered in the container filled with.

The electron conjugated polymer thus obtained
The thickness of the non-woven fabric coated with the resin is preferably at least 0.3 mm so that the cushioning property is excellent, and the more preferable thickness is at least 0.5 mm.

The electron conjugated polymer thus obtained
The fiber sheet coated with over good neutralization properties, yet it is one that does not damage the optical disc, the conductive resin sheet and
Coated with electron conjugated polymer for easy integration
Fiber sheet on one side of the preferred arbitrariness to deposit the adhesive in the gap. As the pressure-sensitive adhesive, for example, acrylate rubber, natural rubber, silicone rubber, polychloroprene, butadiene-styrene copolymer, ethylene-vinyl acetate copolymer, polyisobutylene, solvent type such as polyvinyl ether rubber, Emuljo type and addition reaction type adhesives can be used. These adhesives can be attached, for example, by using a fiber sheet in which the adhesive is coated with an electronic conjugated polymer.
Impregnating the bets, coating, or after spraying, electrostatic applying pressure
The adhesive may be pushed into the voids of the fiber sheet coated with the conjugated polymer . The adhesive is an electronic conjugated polymer.
It is not necessary to adhere to the entire space on one side of the fiber sheet covered with the resin , but may be applied only to a part of the space.

The cushioning material of the present invention is a fiber coated with the above-mentioned electron conjugated polymer in order to further enhance the cushioning property.
Have the Wei sheet and the conductive resin sheet is integrally laminated
You. Examples of the conductive resin sheet include a resin sheet provided with conductivity by metal plating, vapor deposition, sputtering, ion plating, metal spraying, coating with an electron conjugated polymer, or carbon or metal. For example, a resin sheet obtained by mixing a conductive powder such as the above or by polymerizing an electron conjugated polymer inside the sheet can be used. Among these, a resin sheet obtained by mixing a conductive powder or polymerizing an electron conjugated polymer even inside the sheet can be suitably used because of its excellent conductivity in the thickness direction. In addition, if the resin sheet is excellent in elasticity such as rubber and elastomer, it is preferable because the cushioning property can be further improved.

The conductive resin sheet and the electron conjugated polymer
The method of lamination and integration with the fiber sheet coated with the adhesive is not particularly limited, but the adhesive is attached to the fiber sheet coated with the electronic conjugated polymer as described above, and the conductive resin sheet and When laminated and integrated, the electron conjugate system
This is a preferable lamination and integration method because the static elimination property of the fiber sheet coated with the polymer is not impaired.

Since the tray of the present invention uses the above-mentioned cushioning material, spark discharge does not occur when manufacturing an optical disk. Since the electrostatic charges are preferably removed through the tray, the tray is preferably made of a conductive material such as a metal such as stainless steel or aluminum. Since the above-mentioned cushioning material is used by laying under the optical disc, the cushioning material is used at least for the optical disc mounting portion of the tray. If this cushioning material can be firmly fixed to the tray, the printing process etc. can be performed stably ,
It is preferable that the fiber sheet covered with the conjugated polymer is fixed using the elasticity of the conductive resin sheet laminated and integrated.

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. The surface resistance is a value measured by a surface resistance meter (Loresta AP, manufactured by Mitsubishi Yuka Co., Ltd.).

[0023]

Example (Reference Example 1) As shown in FIG.
Dividable fiber with a fineness of 2 denier and a fiber length of 38 mm (fan shape made of polyester component) having a chrysanthemum flower-shaped cross-section divided into eight sections by a polyamide component (B) extending radially from the center of the fiber toward the fiber surface With fiber diameter of 4.2μm
100%, which can be divided into ultrafine fibers having a fiber shape of 6.1 μm in a cross shape made of a polyamide component, and 3.1 μm in a single shape made of a polyamide component.
And a cross fiber web obtained by crossing a unidirectional fiber web similar to this unidirectional fiber web with a cross layer at a weight ratio of 1: 4 to form a laminated fiber. I got the web. After placing this laminated fiber web on a 100-mesh net, water was jetted from a nozzle plate located above the net with a diameter of 0.15 mm and a pitch of 0.6 mm at a pressure of 95 kg / cm ² , and the water was separated. At the same time as splitting the fibers, the laminated fiber web was entangled to obtain a nonwoven fabric having a basis weight of 170 g / m ² and a thickness of 0.7 mm. Then
After impregnating this nonwoven fabric with iron (III) chloride at a concentration of 30%, the pyrrole solution was brought into contact with the evaporated pyrrole monomer gas and polymerized, and the entire nonwoven fabric surface was coated with polypyrrole. The surface resistance was 2 × 10 ² Ω /. The conductive non-woven fabric of □ was obtained. Next, from one side of the conductive non-woven fabric, an acrylic pressure-sensitive adhesive of a water-based emulsion (solid content: 50%, viscosity: 15,000)
0 to 25,000 cps), passed between two steel rolls provided with 0.5 mm slits, and dried at 100 ° C. for 10 minutes to obtain an adhesive-coated conductive nonwoven fabric . The surface resistance of the pressure-sensitive adhesive coating the conductive nonwoven fabric, an adhesive attachment side 5.1 × 10 ² Ω / b, the opposite side is ² × 10 2 Ω /
It was b.

(Reference Example 2) As a fiber sheet, Exeine (registered trademark, manufactured by Toray Industries, Inc., product number 233050) having a basis weight of 120 g / m ² and a thickness of 0.6 mm
Except for using N), the conductive processing and the adhesive adhesion processing were performed in exactly the same manner as in Reference Example 1 to obtain an adhesive-coated conductive fiber sheet.
To obtain the door. The surface resistance of the pressure- sensitive adhesive-coated conductive fiber sheet was 8.5 × 10 ⁵ Ω / b on the side where the pressure-sensitive adhesive was attached, and 2.3 × 10 ⁴ Ω / b on the opposite side.

(Reference Example 3) Acrylonitrile-copper sulfide composite fiber having a fineness of 2 denier and a fiber length of 51 mm (trade name, Sandaron, manufactured by Nippon Silk Wool Dyeing Co., Ltd.) was used in exactly the same manner as in Reference Example 1. The obtained laminated fiber web is needle-punched at a needle density of 75 needles / cm ² , and has a basis weight of 150 g / m ² , a thickness of 1.0 mm, and a surface resistance of 1 × 1.
A conductive non-woven fabric of 0 ² Ω / □ was obtained. Then, the adhesive was applied in the same manner as in Example 1 so that the adhesive-applied side was 2.5 × 1
In 0 ² Omega / b, opposite to 1 × 10 ^{2 Ω} / b of the adhesive coating thereof
A cloth conductive nonwoven fabric was obtained.

(Reference Example 4) Except that no conductive processing was performed (adhesive adhesion processing was performed), all surfaces were 1 × 1 in exactly the same manner as in Reference Example 2.
0 adhesive coating of ⁸ Omega / b or more (not measured by a surface resistance meter)
A fabric fiber sheet was obtained.

(Static neutralization test) A frictional voltage tester (EST-7, manufactured by Kanebo Engineering Co., Ltd.) based on the JIS-L-1092 reference method.
On the sample stage, the adhesive-coated conductive nonwoven of Reference Examples 1 to 4
Cloth, adhesive-coated conductive fiber sheet, or adhesive-coated fiber
After each of the fibrous sheets was placed and a commercially available audio disc was laminated, the disc was rubbed 12 times with a cotton cloth, and the charged voltage on the surface of the audio disc was measured. This measurement was performed at a temperature of 25 ° C. and a humidity of 40%. The results were as shown in Table 1.

[0028]

[Table 1]

(Abrasion test) A 1 mm thick polycarbonate plate was placed on a test piece of a friction tester II type specified in JIS L 0823.
Adhesive-coated conductive nonwoven fabric of Reference Examples 1 to 4,
After applying the agent-coated conductive fiber sheet or the pressure-sensitive adhesive-coated fiber sheet , respectively, and rubbing 10 times, the scratches on the polycarbonate plate surface were visually evaluated. The results are also shown in Table 1.

As can be seen from Table 1, the cushioning material of the present invention
The fiber sheet coated with the electronic conjugated polymer is excellent in both static elimination and abrasion, and is coated with the electronic conjugated polymer that constitutes a buffer when manufacturing optical discs.
It can be seen that this is a suitable fiber sheet .

[0031]

According to the present invention, the cushioning material for manufacturing an optical disk is a fiber sheet coated with an electron conjugated polymer and a conductive resin.
It has excellent static elimination properties because it is laminated and integrated with a fat sheet .
Moreover, since the electron conjugated polymer is soft, it does not damage the optical disk. When the electron conjugated polymer is polypyrrole, the charge elimination property is excellent. Further, when the fibers constituting the fiber sheet include ultrafine fibers having a fiber diameter of 10 μm or less, or fibers having an irregular cross-sectional shape are included, the discharge is more excellent, so that a spark discharge is generated. It is a difficult cushioning material. Furthermore, the nonwoven fabric obtained by the hydroentanglement method is suitable because the orientation direction of the fibers tends to be the thickness direction of the nonwoven fabric and has excellent cushioning properties. Also, it is laminated and integrated with the conductive resin sheet.
More excellent cushioning and firmly attached to the tray
And can be fixed.

Fiber coated with this electron conjugated polymer
On one side of the gap of the sheet, the pressure-sensitive adhesive is adhered, tightly into the conductive resin sheet without impairing the neutralization of fixed
it can.

[0033]

Since the tray of the present invention uses the above-mentioned cushioning material for manufacturing an optical disk, it has excellent static elimination properties and does not damage the optical disk.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an audio disc.

FIG. 2 is an example of a schematic sectional view of a splittable fiber.

FIG. 3 is another example of a schematic cross-sectional view of a splittable fiber.

FIG. 4 (a) Another example of a schematic sectional view of a splittable fiber (b) Another example of a schematic sectional view of a splittable fiber

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material layer 2 Deposition layer 3 Protective layer 4 Printing A One component B Other components

Continuation of the front page (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 7/26 G11B 23/00 H05F 1/00-3/06 B32B 7/02 D04H 1/46 D06M 15/00-15 / 715 D06M 23/00-23/18 F16F 7/00

Claims (7)

(57) [Claims] A fibrous sheet coated with an electron conjugated polymer and a conductive resin sheet are laminated and integrated.
A cushioning material for manufacturing optical discs, characterized by: 2. The cushioning material according to claim 1, wherein the electron conjugated polymer is polypyrrole. 3. The cushioning material for manufacturing an optical disk according to claim 1, wherein the fibers constituting the fiber sheet include ultrafine fibers having a fiber diameter of 10 μm or less. 4. The cushioning material for manufacturing an optical disk according to claim 1, wherein the fibers constituting the fiber sheet include fibers having an irregular cross-sectional shape. 5. The cushioning material for manufacturing an optical disk according to claim 1, wherein the fiber sheet is a nonwoven fabric formed by a hydroentanglement method. 6. The method according to claim 1, wherein:
A cushioning material for manufacturing an optical disk, wherein an adhesive is attached to a gap on one side of a fiber sheet coated with an electronic conjugated polymer . 7. The method according to claim 1, wherein
It is characterized by the use of cushioning material for manufacturing optical discs.
Tray to do.