JPH10264984A - Storage-disk case - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage-disk case which reduces, when an external force acts on a case main body used for substantially storing storage disks, deformation of its side walls to the smallest amount possible, and is stable in a stack of case main bodies or a stack of case main bodies with upper and lower lids fitted on each. SOLUTION: In a storage-disk case 10, its openings are opened/closed by fitting an upper lid 30 and a bottom lid 40 on the top and bottom of a boxlike case main body 20 which is open at the top and bottom and used for holding storage disks D in. The upper lid 30 comprises at least an enclosing hold portion 33, in the shape of an inverted recess, which fits on the upper ends of the case main body 20, rigidity imparted portions 34, formed almost in the middle, which act against deforming forces exerted from the opposite enclosing hold portions 33, and recessed portions 35 consisting of curved faces which continue to the rigidity imparted portions 34 from the lower ends of the inside walls 33a of the enclosing hold potion 33. A distance (l) between the inner surfaces of the inside walls of the opposite enclosing hold portions 33 is made substantially equal to a distance L between the inner surfaces of the opposite upper ends of the case main body 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage disk case, and more particularly, to a storage disk case that can be used as a transport container, for example, in a hard disk manufacturing process or when transporting a completed hard disk to another manufacturing factory. About.

[0002]

2. Description of the Related Art Heretofore, as a storage disk case of this type, there has been known a storage disk package disclosed in Japanese Patent Publication No. 5-55395. The conventional storage disk package disclosed in the above publication basically includes a pair of long side walls facing each other,
There is provided a disc box in which a box whose upper and lower parts are opened by another pair of short side walls facing each other is formed.

[0003] On the inner surfaces of a pair of long side walls of the disk box, a number of grooves for holding a storage disk are formed in parallel along the longitudinal direction. In addition, cutouts are formed in a pair of short side walls of the disk box so that the center hole of the storage disk housed in the disk box is exposed to the outside.

Further, this storage disk package is
An upper cover for closing an open upper portion of the disk box is provided. The upper cover has two tongue pieces that respectively close the cutouts formed in the other pair of side walls of the disc box when attached to the upper opening of the disc box. The storage disk package also includes a lower cover for closing an open lower part of the disk box.

Normally, such a storage disk package is housed in a disk box such that a plurality of storage disks being manufactured are inserted into grooves formed on the inner surfaces of a pair of side walls, and a cleaning process is performed. It is used for cleaning storage disks in the process. It is also used as a packaging container for transporting the completed storage disk to, for example, a drive maker.

[0006] Such a storage disk package includes:
During or after the cleaning process, or after transportation to a drive maker or the like, the upper cover and the lower cover are removed from the disk box, and a notch formed in a pair of short side walls, for example, a take-out rod or the like is inserted into the center hole of the storage disk. It is very excellent as a package for accommodating a storage disk because it can be used in such a way that it can be pierced through and pulled out from the upper opening.

[0007]

However, the conventional storage disk package has the following problems. In other words, when this storage disk package is used as a shipping container, in order to prevent dust from entering the inside during transportation, the outside is tightly covered with a resin film, and the inside is evacuated to form a disk box. The degree of adhesion to the upper and lower covers is increased. However, when the inside of the exterior resin film is evacuated, a deformation force is applied to the disc box due to a difference in pressure between the inside and outside.

At this time, the deformation force applied to the pair of long side walls of the disk box acts as a force for strongly sandwiching the storage disk accommodated in the disk box from both sides thereof, and the storage disk is deformed. It can also be a cause. Therefore, it is necessary to reduce the deformation of each side wall of the disk box as much as possible while increasing the degree of adhesion between the disk box and the upper and lower covers by evacuating the inside of the storage disk package.

Of course, protecting the storage disk housed therein by minimizing deformation in the side wall of the disk box is not limited to the case where the inside of the storage disk package is evacuated. This is extremely effective against external forces that may be applied for some reason when the robot is in operation.

[0010] Further, the disk boxes are stacked in a so-called pyramid shape so that one disk box is laid on two parallel disk boxes for convenience of storage and organization in the manufacturing process of the storage disk. There is. In this case, it is necessary to lock the disk boxes in the horizontal direction.However, in the conventional disk box, the mutual locking is uncertain, and there is a fear that many stacked disk boxes may collapse due to vibration or the like. Was.

Further, when the storage disk package is used as a shipping container, they may be stacked one above the other. For this case, the protrusion formed in the center of the upper cover is fitted to the recess formed in the lower cover to stabilize the stacking. There was also a problem that it was difficult to obtain.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem. When an external force acts on a case body which substantially accommodates a storage disk, the amount of deformation of a side wall of the case body is made as small as possible. It is another object of the present invention to provide a storage disk case that stabilizes the stacking of the case main bodies or stabilizes the stacking of the case main bodies with the top lid and the bottom lid mounted vertically.

[0013]

SUMMARY OF THE INVENTION The present invention is a case for a storage disk, and has the following structure to achieve the above-mentioned technical problem. That is, the present invention provides a box-shaped case body having a large number of grooves formed on the inner surfaces of a pair of opposing side walls in parallel with each other along the longitudinal direction and having an open top and bottom, and The storage disk case, comprising: an upper lid detachably attached to the upper part to open and close an opening; and a bottom lid detachably attached to the lower part of the case body to open and close the opening. Are formed in a substantially concave portion along the longitudinal direction, and a rigid force opposed to a deforming force from the opposing holding portion side. An application part, and at least a depression formed of a curved surface connected to the rigidity application part from the lower end of the inner wall part in the holding part, wherein the inner wall part of the opposing holding parts is Inner surface distance l Characterized in that it is equally serial case phase inner surface spacing L and substantially opposite the upper end of the body.

<Concrete Configuration of the Present Invention> The storage disk case of the present invention is composed of the essential components described above. However, the case is established even when the components are specifically as follows. The specific component, the bottom lid,
A bottom plate, a peripheral wall portion erected from a peripheral portion of the bottom plate so as to be relatively fitted to the outside of a lower end of each side wall in the case main body, and a lower end of the pair of side walls in the case main body fitted to each other; And a reinforcing rib formed integrally with the bottom plate along the peripheral wall portion and over substantially the entire length thereof, and the lower ends of the pair of side walls are fitted with the peripheral wall portion and the reinforcing rib. A substantial fitting groove portion is formed.

Further, in the storage disk case according to the present invention, the bottom cover is provided on the bottom plate and a peripheral wall erected from a peripheral portion of the bottom plate so as to be fitted relatively to the outside of the lower end of each of the side walls of the case body. And a recess formed at a substantially central portion of the lower surface of the bottom plate, and the recess has a shape and size capable of fitting the rigid force applying portion formed on the upper lid in a stable state. Is formed.

Further, in the storage disk case according to the present invention, the other pair of side walls constituting the case main body are inclined so that their lower end sides enter the case main body at least by the thickness of the side wall. And a leg piece protruding from at least a lower end of the outer surface of the other pair of side walls, and an upper end portion of the leg of the case body positioned above when the case bodies are stacked. It is also preferred to form a relatively deep recess in which the pieces fit.

According to the storage disk case of the present invention configured as described above, when the upper lid is put on the upper opening of the case main body, the holding portion of the upper lid has the inner wall portion inside the upper end of the case main body. It fits relatively to the upper end of the case body with almost contact with the peripheral surface. The lower end of the wall inside the holding portion is connected to the rigidity applying portion substantially at the center of the upper lid via a concave portion formed of a curved surface. Therefore, even if a deforming force is applied to the pair of side walls of the case body to press from the outside, the acting force is immediately applied from the lower end of the inner wall of the holding portion to the stiffness applying portion of the central portion via the recessed portion. To prevent the side wall of the case body from being excessively deformed.

When the bottom cover is attached to the lower opening of the case body, the lower ends of the lower walls of the pair of side walls of the case body are connected to the peripheral wall standing upright from the periphery of the bottom plate constituting the bottom cover. Along the entire peripheral wall portion and over substantially the entire length thereof, the rib is inserted into a fitting groove formed by a reinforcing rib integrally formed on the bottom plate. Even if force is applied, this force is immediately received by the reinforcing ribs, preventing excessive deformation of the side wall of the case body, and as a result, preventing the bottom cover from separating from the peripheral wall, so that airtightness inside the case is prevented. Sex can be maintained.

According to the storage disk case of the present invention, a leg piece is formed at least at the lower end of the outer side surface of the other pair of side walls of the case main body, and a relatively deep recess is formed at the upper end. In combination with the fact that the other pair of side walls are formed obliquely, these leg pieces fit into the recesses of the case body located above when the case bodies are stacked, thereby stacking. In this case, the case body can be stabilized.

Further, in the storage disk case of the present invention, a recess is formed at a substantially central portion on the lower surface of the bottom plate constituting the bottom cover, and the recess and the rigidity applying section formed on the upper cover are formed. Are formed in such a shape and size that they can be fitted in a stable state, so that when the storage disk case is stacked up and down, it can be prevented from collapsing due to vibration or the like.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a case for a storage disk according to the present invention. FIG. 1 is a perspective view showing a storage disk case 10 according to an embodiment of the present invention. The storage disk case 10 according to this embodiment includes a case main body 20, an upper lid 30 placed on the upper part thereof, and a bottom lid 40 mounted on a lower part of the case main body 20.

First, the structure of the case body 20 will be described. As shown in FIG. 2, the case body 20 includes a pair of side walls 21 facing each other and another pair of side walls 22 facing each other, and has a box-like shape whose top and bottom are open. The pair of side walls 21 are connected to a substantially vertical upper wall portion 21a, a substantially vertical lower wall portion 21b having a smaller interval than between the upper wall portions 21a, and an upper wall portion 21a and a lower wall portion 21b. Connecting wall 2 having a curved inner surface
1c.

On the inner surfaces of the pair of side walls 21, a number of vertically elongated strip-shaped ridges 23 are formed in parallel at intervals in the longitudinal direction. A groove 24 is formed. Each of these band-shaped ridges 23 is connected to the connecting wall 2 from substantially the upper edge of the side wall 21.
It is formed so as to extend to near the connection between the lower wall 1b and the connection portion 1c.

Grooves 24 appearing between each band-like ridge 23
When the storage disk D is accommodated in the case main body 20 as shown in FIG. 3, the opposing peripheral edge of the storage disk is locked in the longitudinal direction of the case main body 20 by each groove 24,
Determine the mutual holding position. The curved inner surface of the connecting wall 21c is
As described above, the storage disk placed in the case main body 20 functions as a locking portion for preventing the storage disk from dropping downward, that is, a receiving portion.

On the other hand, the other pair of side walls 22 constituting the case body 20 are provided with a storage disk D inside the case body 20.
Is formed, a notch 25 having a size such that the center hole O of the storage disk D is exposed is formed downward from the upper edge. The pair of side walls 22 are formed so as to be slightly inclined so that the interval at the lower end is smaller than the interval at the upper end.

Further, leg portions 26 are formed on the outer surfaces of the side walls 22 so as to protrude. The bottom surface of the leg piece 26 is connected to the lower wall portion 21b that constitutes the pair of side walls 21 described above.
The upper part thereof is connected to a peripheral rib 27 formed on the outer surface at the upper part of the four side walls 21 and 22 of the case body 20. The leg piece 2 is provided at the upper end of the side wall 22.
A relatively deep concave portion 28 is formed with a width that can fit thereinto.

This concave portion 28 is formed in a so-called pyramid shape when straddling one case main body 20 on two parallel case main bodies 20 for convenience of storage and arrangement of the case main bodies 20 in the manufacturing process of the storage disk. It is used as a fitting portion below each leg piece 26 of the case body 20 located above. As a result, even when the case bodies are stacked as described above, a secure locking state can be obtained in the lateral direction, and the collapse of a large number of the stacked case bodies 20 even with a slight vibration can be reliably prevented. it can.

In the case main body 20 configured as described above, the curved inner surfaces of the connecting walls 21c forming the pair of side walls 21 are in point contact with the peripheral edge of the storage disk D accommodated in the case main body 20 at one point P. The lower surface 21c-1
b, and the other inner surface is formed on the storage disk D.
Non-contact concave surface 21c that does not come into contact with the peripheral edge at all
-2, the whole is formed in an S-shaped cross section.

Next, a description will be given of the upper lid 30 which is placed on the upper opening of the case body 20. As shown in FIGS. 1 and 4, the upper lid 30 is formed on a lid main body 31 which is detachably mounted on an upper portion of the case main body 20 and opens and closes an opening portion, and another pair of side walls 22 of the case main body 20. And a tongue-shaped piece 32 formed integrally with the lid body 31 to open and close the cutout portion 25.

The lid body 31 of the upper lid 30 is shown in FIG.
As shown in FIG. 4, an inverted concave holding portion 33 fitted to the upper edge portion of the case main body 20 and a rectangular flat surface formed in a substantially central portion along the longitudinal direction and viewed in a plane. Face part 3
4 and a depressed portion 35 connected from the lower end of the inner wall portion 33a of the holding portion 33 fitted to the upper end portion of the pair of side walls 21 of the case body 20 to the peripheral portion of the flat surface portion 34 described above.
It is composed of

The depression 35 is formed as a curved surface as is apparent from FIG. 3, and the curved wall surface and the inner wall portion 33a of the holding portion 33 are located at a position lower than the lower end of the outer wall portion 33b. They are connected via a radius, that is, a curved corner portion 33d. A large number of protrusions are formed at predetermined intervals on the inner surface of the curved wall surface forming the depression 35 so as to provide a groove for holding the upper peripheral edge of the storage disk D placed in the case body 20. 36 are formed.

When the upper lid 30 is put on the upper opening of the case body 20, the large number of projections 36
The upper peripheral portion of the storage disk D, which is located in the same vertical plane as the plurality of band-shaped ridges 23 formed on the inner surface of the side wall 21 and has a peripheral portion inserted in a groove 24 formed between the band-shaped ridges 23. Can be simultaneously locked between the projecting pieces 36.

Further, on the inner surface of the recessed portion 35, a fin 37 protrudes from the position where the above-mentioned projection piece 36 is formed to a position closer to the holding portion so that the tip end contacts the peripheral portion of the storage disk D.
Are formed integrally along the arrangement direction of the storage disks D and over substantially the entire length of the depression 35. As can be seen from FIG. 3, each of the fins 37 has a leading end in circumferential contact with an upper peripheral portion of a large number of storage disks accommodated in the case body 20 to hold the storage disks.

The fins 37 shown in FIG.
Is formed integrally over almost the entire length of the
Each storage disk D may be formed of a large number of small pieces so as to hold it. If the inner surface of the depression 35 is dimensioned so that the inner surface of the depression 35 comes into contact with the upper peripheral edge of the storage disk, the protrusions 36 and the fins 37 need not be provided.

Both ends of the flat surface portion 34 formed at the center of the lid body 31 are connected to the other pair of side walls 22 of the case body 20.
In order to open and close the notch 25 formed in the cover body 31, it is connected to an end face plate 32 a constituting a tongue-shaped piece 32 formed integrally with the lid main body 31. This end face plate 32a is formed on a flat surface,
An enclosing frame 32b is integrally erected on the outer peripheral edge, and a flange 32c that protrudes outward is integrally formed on an edge of the enclosing frame 32b.

The upper portion of the flange portion 32c has a wall portion 33b outside the holding portion 33 and a wall portion 33 on the upper side, ie, the top surface.
c, and the upper part of the surrounding frame part 32 b is closed as a terminal of the holding part 33. Thereby, the rectangular flat surface portion 34 formed in the center portion of the lid main body 31 is
The end plates 32a of the tongue-like pieces 32, which are substantially perpendicular to each other, are connected to both ends thereof, so that the rigidity is enhanced by presenting an inverted box shape.

As described above, the flat surface portion 34 having a substantially inverted box shape opposes the deformation force from the holding portion 33 side fitted to the upper end portions of the pair of side walls 21 of the case body 20. Functions as a rigidity imparting section. In this case, one end intersects with the outer surface of the inner wall portion 33a of the holding portion 33 at a substantially right angle, and the other end substantially intersects with the vicinity of the connecting portion between the flat surface portion 34 and the curved wall surface of the depression portion 35 at a right angle. If the reinforcing rib pieces (not shown) are formed so as to be connected to each other, the rigidity against deformation in the side direction can be further increased. The flat surface portion 34 functions not only as a rigidity applying portion but also as an interlocking means when the storage disk cases 10 are vertically stacked. This interlocking means will be described later.

By the way, as shown in FIG. 3, the distance l between the inner surfaces of the inner walls 33a of the opposing holding parts 33 constituting the lid body 31 of the upper lid 30 is, as shown in FIG.
Are substantially equal to the inner surface distance L of the upper end portions facing each other. Here, the inner surface distance 1 between the inner wall portions 33a of the holding portion 33 and the inner surface distance L of the upper end portions of the case body 20 opposite to each other are “substantially equal” when the upper lid 30 is When the covering portion 33 is put on the upper opening portion and the holding portion 33 is relatively fitted to the upper end portion of the case main body 20, the clearance S that the inner wall portion 33a opens to the inner peripheral surface of the upper end portion of the case main body 20, 0 to about 0.05 mm or less.

Next, the bottom cover 40 attached to the lower part of the case body 20 will be described. As shown in FIGS. 3 and 5, the bottom lid 40 is formed on a bottom plate 41 and a peripheral wall erected from the periphery of the bottom plate 41 so as to be relatively fitted to the outside of the lower end of each of the side walls 21 and 22 of the case body 20. And a unit 42. A rectangular bulging portion 43 bulging from the lower surface to the upper surface is formed at the center of the bottom plate 41, thereby forming a rectangular recess 44 as viewed in a plane on the lower surface. The bulging portion 43 is formed for the purpose of increasing the rigidity of the bottom plate 41 and fitting the flat surface portion 34 of the upper lid 30 into the concave portion 44 on the lower surface.

Of the peripheral wall portions 42 erected on the four sides of the bottom plate 41, between the two opposing peripheral wall portions in which the lower ends of the pair of side walls 21 of the case body 20 are fitted, and the side wall of the bulging portion 43. A reinforcing rib 45 is formed integrally with the bottom plate 41 along the peripheral wall portion 42. The space between the reinforcing rib 45 and the peripheral wall 42 along the reinforcing rib 45 is a substantial fitting groove 46 into which the lower ends of the pair of side walls 21 in the case body 20 fit. In the embodiment shown in FIG. 5, the reinforcing rib 45 is
3 is formed over substantially the entire length in the longitudinal direction, but may be formed to have a length that functions as reinforcement near a substantially middle portion of the bulging portion 34 in the longitudinal direction.

Between the reinforcing rib 45 and the bulging portion 43,
Three reinforcing rib pieces 47 are formed upright from the bottom plate 41, one end of each reinforcing rib piece 47 is connected to the side face of the reinforcing rib 45 at a right angle and connected to the other side, and the other end is a bulging portion 43.
It crosses at almost right angles to the side surface. The rigidity of the reinforcing rib 45 against deformation in the side direction is enhanced by the reinforcing rib pieces 47 as described above.

Now, such a storage disk case 1 will be described.
When the upper case 30 is provided as a transport container or the like by attaching the upper cover 30 and the lower cover 40 to the upper opening portion and the lower opening portion of the case body 20, respectively, they may be stacked vertically.
In this case, as shown in FIG. 6, the box-shaped portion of the flat surface portion 34 of the upper lid 30 of the lower storage disk case 10 fits into the lower surface recess 44 of the bottom lid 40 of the upper storage disk case 10. Thus, stabilization during loading is achieved.

From this viewpoint, the depth of the recess 44 is about 4 m.
Preferably, the depth is about m. The shape and the size of the lower surface recess 44 of the bottom cover 40 are the flat surface portion 34 of the upper cover 30.
Both are designed so as to correspond to the shape and size of the box-shaped portion.

According to the storage disk case 10 according to the embodiment configured as described above, the upper cover 30 is put on the upper opening after the storage disks D are accommodated in the case body 20. Thereby, the holding part 3 of the upper lid 30
3 is relatively fitted to the upper end of the case main body 20 in a state where the inner wall 33a almost contacts the inner peripheral surface of the upper end of the case main body 20. Therefore, even if a pressing and deforming force is applied to the pair of side walls 21 of the case body 20 from the outside, the acting force is immediately applied to the center of the holding portion 33 from the lower end of the inner wall portion 33 a via the recessed portion 35. It is transmitted to and opposed to the flat surface portion 34 of the portion, thereby preventing the sidewall of the case body 20 from being excessively deformed.

On the other hand, when the bottom cover 40 is attached to the lower opening of the case body 20, the lower ends of the lower walls 21 b of the pair of side walls 21 in the case body 20 are moved from the periphery of the bottom plate 41 constituting the bottom cover 40. Standing peripheral wall portion 42 and reinforcing rib 45
Therefore, even if a deforming force is applied to the pair of side walls 21 of the case body 20 to press the lower ends from the outside, the acting force is immediately applied to the reinforcing ribs 45. As a result, excessive deformation of the lower end of the side wall 21 is prevented. As a result, since the lower end of the side wall 21 does not separate from the peripheral wall portion 42 of the bottom cover 40, the airtightness in the case can be maintained well.

According to the case body 20 of the storage disk case 10, for example, when the storage disks are stacked in a pyramid shape during the manufacturing process, the storage disk case 10 is formed on the upper end surface of the side wall 22 of the case body 20 located above. A relatively deep recess 28 engages a leg piece 26 formed on the outer surface of the side wall 22. Therefore, the case main bodies 20 at the time of stacking are mutually stabilized in the horizontal direction, and do not collapse due to slight vibration.

Further, in the storage disk case 10, a bulging portion 43 is formed substantially at the center of the lower surface of the bottom plate 41 constituting the bottom cover 40, and a relatively deep concave portion 44 is provided on the lower surface thereof. When the disk case 10 is stacked vertically, the box-shaped portion of the flat surface portion 34 of the upper lid 30 of the lower storage disk case 10 fits in the recess 44 in a stable state. It can be reliably prevented from collapsing.

In the case body 20 of the storage disk case 10 according to the embodiment of the present invention described above, a pair of side walls 21 are provided.
A number of band-shaped ridges 23 forming grooves for locking the storage disk extend from the upper edge of the side wall 21 to the vicinity of the connection between the connecting wall 21c and the lower wall 21b. However, as shown in FIG.
May be formed on the upper wall 21a.

A number of band-shaped ridges 23 forming the groove 24
7 is formed on the upper wall portion constituting the side wall 21 as shown in FIG. 7 and is formed so as not to exist at the contact portion between the storage disk D and the inner surface of the connecting wall 21c, the cleaning liquid flowing down the groove portion 24 becomes The component near the contact portion and the surface tension and the like caused by the component can smoothly fall downward without being blocked and prevent water droplets from adhering to the storage disk.

Further, the cleaning liquid after the cleaning is applied to the storage disk D
Is also likely to occur due to the surface tension of the cleaning liquid in a right angle space between the surface near the peripheral edge and the inner surface of the connecting wall 21c. Therefore, if the contact between the storage disk and the inner surface of the connecting wall 21c is a line contact, the attachment range becomes large. However, in the storage disk case 10 according to this embodiment, the peripheral edge of the storage disk D is formed so as to make point contact with the convex surface 21c-1 on the inner surface of the connecting wall 21c. In this case, the range of adhesion of the cleaning liquid can be reduced, and a further drainage effect can be obtained in combination with the above-described configuration.

In the storage disk case according to the above-described embodiment, the convex surface 21c-1 which makes point contact with the peripheral edge of the storage disk D accommodated in the case main body 20 is formed near the connecting portion with the lower wall portion 21b. The other inner surface is formed as a non-contact concave surface 21c-2 so as not to make any contact with the peripheral edge of the storage disk D, so that the whole is formed in an S-shaped cross section, but the storage disk D is received by point contact as shown in FIG. The inner surface shape of the connecting wall may be a concave curved surface formed by an arc having a larger curvature than the storage disk D.

The storage disk case 10 described above is preferably molded from a synthetic resin material having antistatic performance. For example, the storage disk case 10 is a thermoplastic resin obtained by mixing 3 to 30 parts by weight of the component (B) and 5 to 40 parts by weight of the component (C) with respect to 100 parts by weight of the following component (A). It is preferable to be composed of a resin composition. Component (A): Melt flow rate (MFR) is 1 to 80
g / 10 minutes of crystalline propylene resin Component (B): an olefin copolymer elastomer (b ¹ ) having a Mooney viscosity (ML1 ₊₄ (100 ° C.)) of 10 to 85 and a styrene or derivative thereof content of 15 to 50
Weight-average molecular weight of 50,000 to 220,00% by weight
Thermoplastic elastomer selected from hydrogenated styrene or a derivative thereof / conjugated diene block copolymer (b ² ), component (C): acrylamide copolymer

[I] Thermoplastic resin composition (1) Constituent component (a) Crystalline propylene-based resin (component (A)) The crystal used in the thermoplastic resin composition which is the material of the storage disk case of the present invention. Propylene resin is AS
Melt flow rate (MF) according to TM D1238
R, 230 ° C, 2.16 kg load)) is 1 to 80 g / 1
It is a propylene-based resin for 0 minutes, preferably 3 to 60 g / 10 minutes, particularly preferably 3 to 40 g / 10 minutes. The propylene resin has an ethylene content of 0 to 15% by weight, preferably 2 to 12% by weight, particularly preferably 4 to 1% by weight.
A propylene homopolymer and a propylene / ethylene block copolymer having 0 to 20% by weight, preferably 0 to 10% by weight, particularly preferably 0 to 5% by weight, of 0% by weight and α-olefin having 4 to 12 carbon atoms. Examples of the polymer include a propylene / ethylene / butene random copolymer. The crystallinity by X-ray diffraction generally ranges from 50 to
90%, preferably 60-85%, particularly preferably 65%
~ 80%. When a crystalline propylene-based resin having an MFR less than the above range is used, the heat-melt viscosity increases, the moldability is poor, and poor appearance is likely to occur. On the other hand, if the MFR exceeds the above range, the strength of the material decreases, and it cannot be used as a case material. If the crystallinity is less than 50%, the rigidity tends to decrease, while if it exceeds 90%, the impact resistance tends to decrease.

(B) Thermoplastic Elastomer (Component (B)) The thermoplastic elastomer used in the thermoplastic resin composition as the material of the storage disk case of the present invention includes:
Mooney viscosity (ML according to ASTM D1646)
Hydrogenation of olefin copolymer elastomer (b ¹ ) having _{1 + 4} (100 ° C.) of 10 to 85 and styrene or its derivative / conjugated diene block copolymer having styrene or its derivative content of 15 to 50% by weight. (B ² , hereinafter sometimes simply referred to as “styrene-based elastomer”)). When a thermoplastic elastomer other than these is used, the compatibility with the above-mentioned component (A) is poor, which causes delamination. Further, an olefin elastomer is preferable to a styrene elastomer from the viewpoint that good compatibility is exhibited with both the component (A) and the component (C).

The olefin copolymer elastomer (b)
¹ ) The olefin-based copolymer elastomer is a copolymer of ethylene and another monomer, and has a rubbery elasticity and a Mooney viscosity (M) in accordance with ASTM D1646.
L _{1 + 4} (100 ° C.) is 10 to 85, preferably 15 to
80, particularly preferably 20 to 75 olefin copolymer elastomers can be used. In particular,
Ethylene / propylene copolymer elastomer (EP
M), an ethylene / butene-1 copolymer elastomer (E
BM), ethylene-propylene / non-conjugated diene copolymer elastomer (EPDM) using a non-conjugated diene such as 5-ethylidene-2-norbornene, 5-methylene-2-norbornene and dicyclopentadiene. . These olefin copolymer elastomers have a weight average molecular weight of 50,000 to 250,000.
It is preferred to use those of 0, preferably 100,000 to 250,000.

If the Mooney viscosity is less than the above range, the effect as a component for fixing a uniform network dispersion of the acrylamide copolymer as the component (C) is not obtained because the viscosity is too low. Also, since the effect of reinforcing the impact strength is small, the utility is poor. On the other hand, those having a Mooney viscosity exceeding the above range lack the dispersibility in the propylene-based polymer and cause poor appearance, which is poor in practicality.

If the weight average molecular weight is less than the above range, rubber elasticity and mechanical strength of the obtained resin composition tend to decrease. When a resin having a weight average molecular weight exceeding the above range is used, the moldability of the resin composition is reduced, and the appearance of the molded article tends to be poor.

Ethylene / propylene copolymer elastomer (EPM) as olefin copolymer elastomer
When propylene is used, the propylene content is 10 to 60% by weight (the ethylene content is 90 to 40% by weight),
It is preferable to use one having a content of 5 to 55% by weight (ethylene content is 85 to 45% by weight). Here, the propylene content (ethylene content) is a value measured by an infrared spectrum analysis method or the like.

The production method (pellet, veil, crumb, etc.) of these olefin copolymer elastomers when they are used in the production of the composition is not particularly limited. Further, those obtained by subjecting them to a heat treatment in the presence of an organic peroxide and partially cross-linking mainly by radicals may be used.

Hydrogenated product of styrene or its derivative / conjugated diene block copolymer (b ² ) The hydrogenated product of styrene or its derivative / conjugated diene block copolymer is styrene or styrene having a styrene content of 5 to 50% by weight. It is obtained by hydrogenating the derivative / conjugated diene block copolymer. Derivatives of styrene include α-methylstyrene, 1-vinylnaphthalene, 2
-Vinylnaphthalene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-
(Phenylbutyl) styrene and the like. Of these, styrene and α-methylstyrene are preferred.

As general conjugated dienes, butadiene,
For example, there are alkyl-substituted butadiene such as isoprene or 2,3-dimethylbutadiene, methylpentadiene and the like, and mixtures thereof. Preferred conjugated dienes here are butadiene, isoprene or mixtures thereof. When the conjugated diene is a mixture of isoprene and butadiene, the weight ratio of the mixture (isoprene / butadiene) is generally 99 /
The ratio is from 1/1/99, preferably from 90/10 to 30/70, particularly preferably from 80/20 to 40/60. Specifically, styrene / ethylene / butylene / styrene copolymer (SEBS) which is a hydrogenated product of a styrene / butadiene block copolymer, or styrene / ethylene which is a hydrogenated product of a styrene / isoprene block copolymer -Propylene / styrene copolymer (SEPS) and the like. Among these, SEPS is preferred from the viewpoint of compatibility with the component (A) and the component (C).

[0062] As styrene or hydrogenated product of a derivative-conjugated diene block copolymer of b ² components,
It is preferable to use those having a weight average molecular weight of 50,000 to 220,000, preferably 50,000 to 200,000, particularly preferably 50,000 to 150,000. Here, the “weight average molecular weight” is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) under the following conditions. (Conditions) Equipment: 150C ALC / GPC (MILLI
Column: AD80M / S (manufactured by Showa Denko KK) 3 solvents: o-dichlorobenzene Temperature: 140 ° C Flow rate: 1 ml / min Injection volume: 200 μl Concentration: 2 mg / ml (antioxidant 2,6-di 0.2% by weight of t-butyl-p-phenol was added.
Measured at a wavelength of 3.42 μm with an infrared spectrophotometer MIRAN IA manufactured by OXBORO. )

When the weight average molecular weight is less than the above range,
The component (B) forms an orientation-dispersed form in the flow direction, and not only a component in which the component (C) is dispersed in a network cannot be obtained, but also the rubber elasticity and mechanical strength of the obtained resin composition tend to decrease. . Further, when a resin having a weight average molecular weight exceeding the range of the note is used, the moldability of the obtained resin composition is reduced, and the appearance of the molded article tends to be poor. The content of styrene or its derivative in the styrene or its derivative / conjugated diene block copolymer is 15 to 50% by weight, preferably 18 to 45% by weight, and particularly preferably 20 to 40% by weight.
It is.

When the content of styrene or its derivative is less than the above range, the obtained resin composition is inferior in rubber elasticity and strength and is not practical. If the content of styrene or its derivative exceeds the above range, the compatibility with the acrylamide copolymer of the component (C) and the crystalline propylene resin of the component (A) is reduced, and the resin composition is stored and stored. When used as a transport case, the impact strength tends to be insufficient. Further, the hydrogenation rate of the styrene or its derivative / conjugated diene block copolymer is generally 95% by weight or more, preferably 97 to 100% by weight, from the viewpoint of weather resistance. When the thermoplastic elastomer is not present, the acrylamide-based copolymer is not uniformly dispersed in a network, as described later, so that delamination tends to occur.

(C) Acrylamide-based copolymer (component (C)) As the acrylamide-based copolymer used in the thermoplastic resin composition which is the material of the storage disk case of the present invention, the following or those described below are used. Can be mentioned. Such an acrylamide copolymer is disclosed in, for example, JP-A No. 4-19.
It can be produced by a known method described in JP-A-8308 and JP-A-7-126446. General formula

[0066]

Embedded image

Ethylene structural units 65 to 99 represented by
Mol%, preferably 85-97 mol%, of the general formula

[0068]

Embedded image

(Wherein R ¹ represents an alkyl group having 1 to 4, preferably 1 to 2 carbon atoms) 0 to 15 mol%, preferably 3 to 7 mol% of an acrylate structural unit represented by the following formula:
And general formula

[0070]

Embedded image

Wherein R ² is an alkylene group having 2 to 8 carbon atoms, preferably 2 to 3 carbon atoms, and R ³ and R ⁴ each have 1 carbon atom.
To 4, preferably 1 to 2 alkyl groups, R ⁵ is C 1 -C
To 12, preferably 1 to 2 alkyl groups, 1 to 1 carbon atoms
2 arylalkyl group or an alicyclic alkyl group having 1 to 12 carbon atoms, X ^- a halogen ion, preferably Cl ^- ion, CH ₃ OSO ₃ ^- or C ₂ H ₅ 0SO ₃ ^- shows the. ) The acrylamide structural unit represented by 1 to 35 mol%, preferably 3 to 15 mol%, has a weight average molecular weight of 1,000 to 50,000, preferably 3,000 to 35,000, which is linearly and irregularly arranged. Is an acrylamide copolymer.

Alternatively, the general formula

Embedded image

Ethylene structural units 65 to 99 represented by
Mol%, preferably 85-97 mol%,

[0074]

Embedded image

(Wherein R ¹ represents an alkyl group having 1 to 4, preferably 1 to 2 carbon atoms) 0 to 15 mol%, preferably 3 to 7 mol% of an acrylate structural unit represented by the following formula:
And general formula

[0076]

Embedded image

(Wherein, R ² is an alkylene group having 2 to 8, preferably 2 to 3 carbon atoms, and R ³ and R ⁴ are each a group having 1 carbon atom.
And 4, preferably 1 to 2, alkyl groups. ) Acrylic amide structural unit represented by the following formula, having a weight average molecular weight of 1,000 to 5
It is an acrylamide copolymer having a molecular weight of 000, preferably 3,000 to 35,000.

When the proportion of the ethylene structural unit is less than 65 mol%, the softening point of the acrylamide copolymer becomes low, and tack or stickiness occurs in the thermoplastic resin composition. The antistatic performance of the acrylamide copolymer is undesirably reduced. Also,
The proportion of the acrylate structural unit is preferably 15 mol% or less, particularly preferably 3 to 7 mol%, from the viewpoint of the balance between the softening point and the impact resistance. When the proportion of the acrylamide structural unit is less than 1 mol%, the antistatic performance is reduced.
If the amount exceeds mol%, the thermoplastic resin composition is not preferable because it becomes hygroscopic.

When the weight average molecular weight is less than 1,000, the acrylamide copolymer becomes waxy, and the handleability becomes poor. On the other hand, if it exceeds 50,000, the compatibility with the propylene-based resin or the thermoplastic elastomer deteriorates, which is not preferable. The weight average molecular weight was measured by gel permeation chromatography (GP
C) The weight average molecular weight in terms of polystyrene performed by the method C. Specifically, an ultra-high temperature GPC method (“Polymer Paper Collection No. 44
Vol. 2, No. 2, Kinukawa, pp. 139-141). In addition, the copolymer represented by the general formula among the acrylamide-based copolymers is specifically marketed as “Leorex AS170” manufactured by Daiichi Kogyo Seiyaku.

(2) Compounding Amount of Each Component (a) Compounding Amount of Crystalline Propylene Resin [Component (A)] The compounding amount of each component in the thermoplastic resin composition used for the storage disk case of the present invention is as follows. The component (B) and the region (C) are blended based on 100 parts by weight of the crystalline propylene resin of the component (A). (b) Blending amount of thermoplastic elastomer [component (B)] The thermoplastic elastomer is 3 to 30 parts by weight, preferably 5 to 20 parts by weight, based on 100 parts by weight of the propylene resin of the component (A). Particularly preferably, it is used in a ratio of 8 to 15 parts by weight. When the amount of the thermoplastic elastomer is less than the above range, the effect of fixing a uniform network dispersion of the acrylamide copolymer of the component (C) is small, and the impact resistance is sufficient as a storage / transport case for a storage disk. Not only is not obtained, but also the vibration and rubbing when the storage disk is stored and transported causes the resin component to be delaminated or detached, thereby contaminating the storage disk. If the amount of the thermoplastic elastomer exceeds the above range, the effect of fixing a uniform network dispersion of the acrylamide copolymer of the component (C) is not only saturated, but also the rigidity is significantly reduced.

(C) Amount of Acrylamide Copolymer [Component (C)] The acrylamide copolymer is 5 to 40 parts by weight based on 100 parts by weight of the component (A) crystalline propylene resin. Preferably 10 to 35 parts by weight, particularly preferably 15 parts by weight
It is used in a proportion of up to 30 parts by weight. If the amount of the acrylamide copolymer is less than the above range, the desired antistatic effect cannot be obtained. On the other hand, if the amount of the acrylamide copolymer exceeds the above range, the rigidity is remarkably reduced, and sufficient rigidity as a storage / transport case for a storage disk cannot be obtained.

(3) Other Components (Component (D)) The thermoplastic resin composition used in the storage disk case of the present invention may contain an antioxidant, a light stabilizer,
A coloring agent such as a lubricant, a flame retardant, a dispersant, a dye, and a pigment, and other optional components such as an inorganic filler and an organic filler can be compounded. In particular, the thermoplastic resin composition used for the storage disk case of the present invention includes a thermoplastic resin composition 10 comprising the above components (A) to (C) as a coloring agent.
A case colored by 0.01 to 1 part by weight with respect to 0 part by weight according to various uses can be obtained.

(4) Production of Thermoplastic Resin Composition The thermoplastic resin composition used for the storage disk case of the present invention contains the above components (A) to (C) and, if necessary, component (D) in the above mixing ratio. And kneading and granulating using an ordinary kneading machine such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roll mixer, a Brabender plastograph, a kneader blender and the like.

In this case, it is preferable to select a kneading / granulating method capable of improving the dispersion of each component. Usually, kneading / granulating is carried out using a twin-screw extruder. During the kneading / granulation, the components (A), (B), (C) and optionally the component (D) may be simultaneously kneaded. Split the components,
That is, the split kneading in which component (A) and part or all of component (B) are mixed and kneaded first, and then component (C) and decrement (D) are mixed and kneaded and granulated is performed. preferable. This is because the component (C) does not have sufficient heat resistance stability and is decomposed in proportion to the heat history at the time of kneading, which may lower the conductivity of the resin composition.

That is, in the case of simultaneous kneading, when the matrix resin (component (A) + component (B)) is plasticized in an extrusion kneader, shear heat is generated during solid phase kneading. Since the temperature is higher than the temperature, decomposition may occur under the influence of such heat. However, according to the method of post-adding the component (C) after the matrix resin has been plasticized by split kneading, Since the influence of the heat generated by shearing can be avoided, there is no possibility that the component (C) is thermally decomposed, and a decrease in the conductive performance can be prevented.

The kneading temperature (cylinder temperature) in the melt extrusion kneading is generally from 150 to 250 ° C., preferably from 18 to 250 ° C.
The temperature is 0 to 230 ° C, particularly preferably 200 to 210 ° C. If the temperature is lower than 150 ° C., the viscosity difference between the component (A) and the component (B) is large, and it is difficult to obtain a uniform composition.
On the other hand, when the temperature exceeds 250 ° C., the thermal decomposition of the component (C) may occur. The kneading time is 0.5 to 10 minutes, preferably 1 to 5 minutes, particularly preferably 2 to 4 minutes.
If the time is less than 0.5 minute, the plasticization of the component (A) is insufficient, and it is difficult to obtain a uniform composition.
If the time exceeds minutes, the thermal stability of component (C) may be impaired, which is not preferred. The kneading time in the case of performing the above-described split kneading is as follows.
It is preferable to knead for 5 to 2 minutes, preferably for 1 minute (kneading in the first stage), then add the component (C) and knead for 0.5 to 2 minutes, preferably 1 minute (kneading in the second stage). It is preferable that the kneading temperature (cylinder temperature) during the division kneading be kept constant between the former kneading and the latter kneading.

[II] Molding Using the thermoplastic resin composition having excellent antistatic properties thus obtained, a storage disk case can be generally molded by an injection molding method. The injection molding temperature is usually about 200 to 210 ° C, and the mold temperature is about 30 to 60 ° C.

[III] Microstructure When the microstructure of the thermoplastic resin composition used in the storage disk case of the present invention is observed with an electron microscope, the presence of the above-mentioned specific type of thermoplastic elastomer reveals A uniform network dispersion of the acrylamide copolymer is formed in the thermoplastic resin composition via the thermoplastic elastomer of the component (B).
On the other hand, when the thermoplastic elastomer is not present, a uniform network dispersion of the acrylamide-based copolymer is not formed in the thermoplastic resin composition, and the acrylamide-based copolymer is heated due to shearing during molding. An aggregate layer is formed near the surface of the plastic resin composition to form a layer. Therefore, in a storage disk case molded from such a microstructured thermoplastic resin composition, the acrylamide-based copolymer gathered near the surface of the thermoplastic resin composition forms a heterogeneous layer. Therefore, it is observed that delamination occurs at this portion, and separation and detachment occur on the storage disk, thereby causing contamination of the storage disk.

[0089]

As described above, according to the storage disk case of the present invention, when the upper lid is covered on the upper open portion of the case main body, the inner wall of the holding portion of the upper lid is formed by the case main body. Even when a deforming force is applied to the pair of side walls of the case body from the outside to act on the pair of side walls of the case body so as to be fitted relatively to the upper edge of the case body in a state of being almost in contact with the inner peripheral surface of the upper edge part, this acting force Is immediately transmitted from the lower end of the wall portion inside the holding portion to the rigidity imparting portion at the central portion via the recessed portion to oppose it, whereby excessive deformation of the side wall of the case body can be prevented.

When the bottom lid is attached to the lower opening of the case body, the lower ends of the lower walls of the pair of side walls in the case body are fitted with the peripheral wall of the bottom lid and the reinforcing ribs. Even if a deformation force is applied to the pair of side walls of the case body that presses from the outside, the force is immediately received by the reinforcing ribs, and excessive deformation of the side walls of the case body is prevented. As a result, separation from the peripheral wall of the bottom lid is also prevented, so that the airtightness in the case can be maintained.

Further, according to the storage disk case of the present invention, at least the lower end of the outer side surface of the other pair of side walls in the case main body is formed with a leg piece protruding, and the upper end is formed with a relatively deep concave portion. In combination with the fact that the other pair of side walls are formed obliquely, these leg pieces fit into the recesses of the case body located above when the case bodies are stacked, thereby stacking. In this case, the case body can be stabilized.

Further, according to the storage disk case of the present invention, a recess is formed at a substantially central portion of the lower surface of the bottom plate constituting the bottom cover, and the recess and the rigidity imparting portion formed on the upper cover are formed. Are formed in such a shape and size that they can be fitted in a stable state, so that it is possible to prevent the storage disk case from being collapsed due to vibration or the like when it is stacked up and down.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a storage disk case according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a case main body constituting the storage disk case shown in FIG. 1;

FIG. 3 is a cross-sectional view of the storage disk case shown in FIG. 1 in which a storage disk is accommodated in a case main body, taken along line 3-3.

FIG. 4 is a perspective view showing an upper lid constituting the storage disk case shown in FIG. 1;

5 is a perspective view showing a bottom cover constituting the storage disk case shown in FIG. 1;

FIG. 6 is a cross-sectional view similar to FIG. 3, showing the storage disk case shown in FIG.

FIG. 7 is a perspective view showing a case main body in a storage disk case according to another embodiment of the present invention.

FIG. 8 is a partial sectional view schematically showing a state of contact with a storage disk in a case main body in a storage disk case according to still another embodiment of the present invention.

[Explanation of symbols]

 D Storage disk O Center hole 10 Storage disk case 20 Case body 21 Side wall 22 Side wall 23 Belt-shaped ridge 24 Groove 25 Notch 26 Leg piece 27 Peripheral rib 30 Top lid 31 Lid body 32 Tongue piece 33 Holding part 34 Flat Surface part 35 Depressed part 36 Projection piece 37 Fin 40 Bottom lid 41 Bottom plate 42 Peripheral wall part 43 Swelling part 44 Recess 45 Reinforcing rib 46 Fitting groove part

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Takeshi Hatakeyama 3-10 Ushidori, Kurashiki City, Okayama Prefecture Inside Mitsubishi Chemical Mizushima Plant (72) Inventor Tohru Shimobukie 3-10 Utsudori, Kurashiki City, Okayama Prefecture Mitsubishi Chemicals Mizushima Office

Claims (4)

[Claims] 1. A box-shaped case main body having a plurality of grooves formed in the inner surfaces of a pair of opposing side walls in parallel with each other along the longitudinal direction and having an open top and bottom, and In a storage disk case comprising a top cover detachably attached to an upper portion to open and close an opening portion and a bottom cover detachably attached to the lower portion of the case body to open and close an opening portion, wherein the top cover is An inverted concave holding portion fitted to an upper end portion of the case main body; and a stiffening force formed substantially at a center portion and along a longitudinal direction to oppose a deformation force from the opposing holding portion side. And a depression formed of a curved surface connected to the rigidity applying portion from the lower end of the inner wall portion of the holding portion, and the inner surfaces of the inner wall portions of the holding portion facing each other. The interval l is Case for memory disks which is characterized by being substantially equal to the inner surface spacing L of the upper end portion facing each of the scan body. 2. The case body according to claim 2, wherein the bottom cover is a bottom plate, a peripheral wall portion erected from a peripheral portion of the bottom plate so as to be relatively fitted to a lower end outside of each of the side walls of the case main body, And a reinforcing rib formed along the opposed peripheral wall portion with which the lower end of the side wall is fitted and substantially integrally rising from the bottom plate over substantially the entire length thereof, and the peripheral wall portion and the reinforcing rib 2. The storage disk case according to claim 1, wherein a substantially fitting groove portion in which lower ends of the pair of side walls are fitted is formed. 3. A bottom plate, a peripheral wall portion erected from a peripheral portion of the bottom plate so as to be relatively fitted to an outer side of a lower end of each side wall of the case body, and a substantially lower surface of the bottom plate. And a recess formed in a central portion, wherein the recess is formed in a shape and size capable of fitting the rigid force applying portion formed in the upper lid in a stable state. The storage disk case according to claim 1. 4. The other pair of side walls forming the case main body are formed so that their lower ends are inclined toward the inside of the case main body by at least the thickness of the side wall, and the other pair of side walls is further formed. At least at the lower end of the outer surface of the side wall of the side wall, a leg piece is formed so as to protrude, and a concave portion is formed at the upper end portion with which the leg piece of the case body located above when the case bodies are stacked is fitted. The storage disk case according to claim 1, 2 or 3, wherein: