JP3068824B1 - Resin composition for optical recording medium tray - Google Patents

Abstract

An object of the present invention is to provide a resin composition for an optical recording medium tray in which generated abrasion powder hardly affects a recording medium. SOLUTION: The present invention relates to a resin composition for an optical recording medium tray, wherein a resin is mixed with a high molecular weight polyolefin resin and a phosphazene as an abrasion fine particle inhibitor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for an optical recording medium tray, and more particularly, to a CD, MD, and DVD.
Alternatively, the present invention relates to a resin composition for an optical recording medium tray suitable as a material for forming a tray for an optical recording medium such as an LD.

[0002]

2. Description of the Related Art In recent years,
As a large-capacity optical recording medium for recording sound, video, information, etc.
CD (compact disc), MD (mini disc),
DVDs (digital video discs), LDs (laser discs), and the like are widely used. There is a so-called disk tray that handles loading and unloading of devices as one of the device components that handle these disks. The parts need to have good slidability because they slide with the equipment body during use, and minimize damage to the disk surface due to friction when the disk is accidentally brought into contact with the tray. It is desirable that the material has a high surface smoothness. Furthermore, if fine powder is generated due to frictional wear, the fine powder may hinder reading of an optical record. Therefore, it is desirable to use a material in which the generation of fine powder is suppressed as much as possible.

The present inventors have repeatedly studied to develop a material that satisfies these characteristics required for a disc tray material. However, no matter how much the slidability is improved, since the material is a sliding member, Abrasion could not be eliminated, and thus it was also impossible to eliminate the generation of abrasion powder.

Accordingly, the present inventors have changed the idea and developed a material which minimizes the influence of the generated wear powder on the recording medium on the assumption that the generation of wear powder is inevitable. There are no new challenges addressed.

[0005]

Under such a problem, as a result of intensive studies, it has been found that a material capable of minimizing the influence on a recording medium can be obtained by the following means, and the present invention has been completed. I let it.

That is, the present invention relates to a resin composition for an optical recording medium tray, comprising a resin and a high-molecular-weight polyolefin resin and a phosphazene as an abrasion fine powder inhibitor. Furthermore, the present invention provides at least one selected from the group consisting of polycarbonate, a polymer alloy of polycarbonate and polybutylene terephthalate (PC / PBT alloy), a polymer alloy of polycarbonate and acrylonitrile-butadiene-styrene (PC / ABS alloy), and a modified polyphenylene ether. The present invention relates to a resin composition for an optical recording medium tray, comprising a high-molecular-weight polyolefin resin and a phosphazene as a fine-wear inhibitor for a kind of resin.

The effect of the above resin composition for an optical recording medium tray is not clear by blending a high molecular weight polyolefin resin and phosphazene into the resin, but the amount of generated abrasion powder is reduced and the generated abrasion is reduced. The size of the powder can be increased and scattering to the surroundings can be suppressed. Therefore, there is little possibility that the optical pickup or the disk recording surface is contaminated, and the reading error can be remarkably suppressed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin (excluding high molecular weight polyolefins) that can be used in the resin composition for optical recording medium trays of the present invention is not particularly limited, and various thermoplastic resins or thermosetting resins can be used. Resin can be exemplified. Examples of the thermoplastic resin include olefin resins such as polyethylene and polypropylene (however, excluding high-molecular-weight polyolefin), polystyrene, acrylonitrile-butadiene-
Styrene resin, polyamide, polyethylene terephthalate, polybutylene terephthalate, polycarbonate,
Examples include polyarylate, polyphenylene ether, modified polyphenylene ether, polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamideimide, polyetherimide, polyketone, polyetherketone, polyetheretherketone, and liquid crystalline polyester. These resins may be used alone, polyphenylene ether and polystyrene, polycarbonate and polybutylene terephthalate,
Two or more kinds such as polycarbonate and acrylonitrile-butadiene-styrene resin may be used in combination. When combining two or more kinds of the above thermoplastic resins, when combining resins having poor compatibility, such as a combination of polycarbonate and acrylonitrile-butadiene-styrene resin, a compatibilizer having compatibility with both resins. Can also be blended. As such a compatibilizer, a conventionally known one can be widely used.

Further, examples of the thermosetting resin include unsaturated polyester resin, phenol resin, epoxy resin and the like.

The high-molecular-weight polyolefin resin used as an abrasion-inhibiting agent in the resin composition for an optical recording medium tray of the present invention has an average molecular weight of 50,000 or more, preferably 50,000 to 300,000, as measured by a viscosity method. Homopolymers such as polyethylene, polypropylene, etc .; copolymers of a plurality of these or these with other vinyl monomers; and modified products thereof.

Examples of the modified product include those obtained by graft-modifying a vinyl monomer to high-molecular-weight polyethylene. Examples of the modified vinyl monomer include acrylic acid, methacrylic acid, ethyl acrylate, ethyl methacrylate and acrylic Methyl acrylate, methyl methacrylate,
Glycidyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, maleic acid, itaconic acid, fumaric acid, maleic anhydride, itaconic anhydride, acrylonitrile, methacrylonitrile, vinyl propionate, vinyl acetate, vinyl caproate, vinyl caprylate Organic acids such as vinyl, vinyl laurate, vinyl stearate, vinyl trifluoroacetate, acrylamide and methacrylamide and derivatives thereof can be exemplified. These can be used alone or in combination of two or more.

As a method of graft-modifying a high-molecular-weight polyethylene with these vinyl-based monomers, a method of mixing the high-molecular-weight polyethylene and the vinyl-based monomer and starting the radical polymerization of an organic peroxide, an azo compound or the like while heating as necessary. An agent may be added. Also, for the purpose of improving the graft ratio and preventing the reduction of the molecular weight, a vinyl aromatic monomer,
For example, styrene, methylstyrene, dimethylstyrene, ethylstyrene, isopropylstyrene, chlorostyrene, α-methylstyrene, α-ethylstyrene and the like may be used. Such a method can be performed, for example, according to the method described in JP-A-1-131220.

The high molecular weight polypolyolefin used in the present invention preferably has a particle size of 1 to 200 μm, and particularly preferably a fine powder having a particle size of 1 to 100 μm. As the compounding amount of the high molecular weight polypolyolefin,
The content is preferably 1 to 50% by weight, preferably 1 to 30% by weight in the total composition.

The phosphazene as an abrasion-suppressing agent incorporated in the resin composition for an optical recording medium tray of the present invention is represented by the following general formula (1):

[0015]

Embedded image [In the formula, m represents an integer of 3 to 25. R ¹ and R ² are the same or different and represent a C 1-8 alkyl group, a C 1-8 alkyl group and / or a phenyl group which may be substituted with an allyl group. ]

A cyclic phosphazene compound represented by the following general formula (2):

[0017]

Embedded image [In formula, n shows the integer of 3-1000. R ³ and R ⁴ are the same or different and each have an alkyl group having 1 to 8 carbon atoms,
8 represents a phenyl group which may be substituted with an alkyl group and / or an allyl group. X is a group _{^{-N = P (OR 3) 3}} , group _{^{-N = P (OR 4) 3}} , a group -N = P (O) (OR 3) or a group -N = P (O) (OR 4) Show. Y is a group -P (O
R ³ ) ₄ , group —P (OR ⁴ ) ₄ , group —P (O) (OR ³ ) ₂ or group —P (O) (OR ⁴ ) ₂ . ]

A linear phosphazene compound represented by the formula:
And at least one phosphazene compound selected from these cyclic and linear phosphazene compounds is represented by the formula:
-, M- or p-phenylene group, biphenylene group, and the following general formula (3)

[0019]

Embedded image[Wherein, r represents 0 or 1, A represents a group —SO_Two-, -S-,
-O- or -C (CH_Three) _TwoIndicates-. ]

The substituents R ¹ , R ² , R ³ , and at least one crosslinking group selected from the group consisting of the groups represented by
Examples include a phosphazene compound in which an alkyl group or the like is eliminated from R ⁴ and two oxygen atoms are cross-linked.

Specific examples of the cyclic phosphazene compound represented by the general formula (1) include hexaphenoxycyclotriphosphazene, octaphenoxycyclotetraphosphazene, decafenoxycyclopentaphosphazene, hexapropoxycyclotriphosphazene, octapropoxycyclocyclotetraphosphazene and Cyclic phosphazene compounds such as decapropoxycyclopentaphosphazene; Specific examples of the linear phosphazene represented by the general formula (2) include a linear phosphazene compound in which a linear dichlorophosphazene is substituted with a propoxy group and / or a phenoxy group.

Specific examples of the crosslinked structure represented by the general formula (3) include, for example, 4,4'-sulfonyldiphenylene (bisphenol-S residue), 4,4'-oxydiphenylene group, '-Thiodiphenylene group, 4,4'-
A diphenylene group and the like can be mentioned. These phosphazene derivatives may have an amino group and / or a phenylamino group substituted at an arbitrary position. One of these phosphazene derivatives may be used alone, or a mixture of two or more thereof may be used. Further, a mixture of a cyclic phosphazene and a linear phosphazene may be used.

The amount of phosphazene in the resin composition is from 0.1 to 80% by weight, preferably from 0.5 to 25% by weight, more preferably from 2 to 15% by weight in the total composition. Good. In the resin composition of the present invention, potassium titanate fiber, aluminum borate fiber, magnesium borate fiber, glass fiber, carbon fiber, mica, flaky filler, wollastonite, as long as the effects of the present invention are not impaired. , Zonotolite and other reinforcing materials, talc and other fillers, titania and other pigments, antioxidants, tin oxide coated potassium titanate fibers, antistatic agents such as carbon black, lubricants, heat stabilizers, flame retardants, plasticizers and fluorine resin,
A lubricant such as molybdenum disulfide or graphite may be blended.

Among them, when potassium titanate fiber, wollastonite or flaky filler is blended, mechanical strength can be improved without deteriorating friction and wear characteristics, and it is particularly preferable as a tray material. The content of the potassium titanate fiber and / or wollastonite is 2 to 40 parts by weight, preferably 5 to 30 parts by weight in the whole composition.
It is good to use parts by weight. These inorganic fillers can be used without any treatment, but depending on the purpose such as aminosilane, epoxy silane, silane coupling agent such as acrylic silane or titanate coupling agent, etc. It may be used after surface treatment with a surface treatment agent.

The resin composition of the present invention is prepared, for example, as follows. That is, after the respective components are uniformly mixed using a blender or the like, the mixture is melted and kneaded with an extruder to obtain a desired resin composition. The obtained resin composition may be directly formed into a desired tray shape by means of injection molding or the like, or may be once pelletized using a pelletizer or the like, and stored, distributed, or used. A member formed by molding the resin composition for an optical recording medium tray of the present invention has a small amount of abrasion due to sliding, and a small amount of abrasion powder is also abrasion powder of a conventional material (median diameter: about 10 to 50 μm). It has an excellent feature that it has a large size (100 to 1000 μm in median diameter) and is less likely to scatter around and contaminate the optical pickup element and the disk surface.

[0026]

EXAMPLES The components shown in Table 1 were compounded using a tumbler mixer, and a twin screw extruder (made by Ikegai Co., Ltd.) was used.
Examples 1 to 1
0 and pellets of the resin compositions of Comparative Examples 1 to 3 were obtained.

The components shown in Table 1 were as follows. Polycarbonate resin (trade name: "SUPIK
A ", manufactured by Mitsubishi Engineering-Plastics Corporation, polybutylene terephthalate resin (trade name:" Trecon 1100S ", manufactured by Toray Industries, Inc.), modified polyphenylene ether resin (trade name:" Zylon 300H ",
Asahi Kasei Corporation), acrylonitrile butadiene styrene resin (trade name: "Santac UT61", manufactured by Mitsui Chemicals, Inc.), high molecular weight polyethylene resin (trade name:
"Hizex 2100CP", MN = 11,000, Mw
= 100,000, manufactured by Mitsui Chemicals, Inc., polytetrafluoroethylene (trade name: “AFLON L169J”, manufactured by Asahi Glass Co., Ltd.), phenoxyphosphazene (trade name: “SP”)
-100 ", manufactured by Otsuka Chemical Co., Ltd., potassium titanate fiber (trade name:" Tismo N102 "), potassium hexatitanate fiber surface-treated with an epoxy coupling agent,
Average fiber diameter 0.4 μm, average fiber length 15 μm, manufactured by Otsuka Chemical Co., Ltd., calcium silicate fiber (trade name: “Vistal”, average fiber diameter 2.2 μm, average fiber length 30 μm,
Wollastonite washed and classified product, manufactured by Otsuka Chemical Co., Ltd., scaly filler (obtained by swelling and peeling mica, average diameter 3 μm, average thickness 0.1 μm).

Each of the obtained resin compositions was injection-molded to obtain a friction / wear test ring (inner diameter 20 mm, outer diameter 25.6 mm, height 15 mm) and various JIS test pieces.

The tensile strength, bending strength, I
The ZOD impact value, mold shrinkage and friction and wear performance were measured. Table 1 shows the results. In addition, the tensile strength is JIS K-
The flexural strength was measured according to 7113, and was measured according to JIS K-72.
03 according to JIS K-
It was measured according to 7110. The molding shrinkage ratio is JIS K
The die size and the actual size of the −7113 tensile test piece were measured, and the values were calculated by substituting into {{(die size) − (actual size of test piece)} / (die size)} × 100.

[0030]

[Table 1]

Further, the dynamic friction coefficient and the specific wear amount of each test piece were measured. This is a glass flake reinforced PBT / AB molded into a cylindrical shape using a Suzuki abrasion tester (manufactured by Orientec Co., Ltd.) as the mating material of the test piece.
Surface pressure 0.06MP using S alloy (trade name: "Duranex 751SA", manufactured by Polyplastics Co., Ltd.)
a, peripheral speed 0.1 m / s, test time 24 hours, distance 8.
It was measured under the condition of 6 km. Further, the wear powder generated in the above test was observed with a scanning electron microscope, and the size of the wear powder was measured. Those having an average particle size of at least 100 μm were determined to be large, and those having a mean particle size of less than 100 μm were determined to be small. Table 1 also shows the results. Further, Example 1 and Comparative Example 1
1 and 2 show enlarged photographs of wear powder generated from the test piece of FIG. In the drawing, 50U indicates 50 μm.

As is clear from FIGS. 1 and 2, the abrasion powder generated from the resin compositions of the respective examples is larger than the abrasion fine powder generated from any of the comparative examples, and scattering occurs. Thus, it was confirmed that the pickup and the disk surface were less likely to be contaminated and could be easily removed.

[0033]

According to the resin composition of the present invention, the friction and wear characteristics can be remarkably improved, and the wear amount is small.
Further, since the generated wear powder is coarse, scattering of the wear powder hardly occurs. Therefore, it is suitable as a material for an optical recording medium tray.

[Brief description of the drawings]

FIG. 1 is an enlarged photograph of wear powder generated from a test piece of Example 1.

FIG. 2 is an enlarged photograph of abrasion powder generated from a test piece of Comparative Example 1.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08L 69/00 C08L 69/00 71/12 71/12 G11B 17/04 315 G11B 17/04 315Y (72) Inventor Yuji Tada Tokushima 463 Kasuno, Kawauchi-machi, Tokushima-shi, Tokushima Otsuka Chemical Co., Ltd. Tokushima Research Laboratory (56) References JP-A-7-292233 (JP, A) JP-A-5-339486 (JP, A) JP-A-9-302209 (JP) , A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/16 C08K 3/00-13/08

Claims (2)

(57) [Claims] 1. A resin composition for an optical recording medium tray, comprising a resin and a high molecular weight polyolefin resin and a phosphazene as an abrasion powder inhibitor. 2. The light according to claim 1, wherein the resin is at least one selected from polycarbonate, a polymer alloy of polycarbonate and polybutylene terephthalate, a polymer alloy of polycarbonate and acrylonitrile-butadiene-styrene, and a modified polyphenylene ether. Resin composition for recording medium tray.