JPS62252582A - Magnetic disk cartridge - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic disk cartridge using a flexible cartridge case or a cartridge case molded from hard synthetic resin.

Especially regarding the cleaning sheet.

[Conventional technology]

A magnetic disk cartridge includes a cartridge case having a magnetic head insertion slot and a rotation drive hole, a flexible magnetic disk rotatably housed within the cartridge case, and a cleaning sheet supported on the inner surface of the cartridge case. It is mainly composed of.

[Problem that the invention seeks to solve]

By the way, conventional cleaning sheets for magnetic disk cartridges are made of a single layer of nonwoven fabric such as mixed fibers of rayon and polypropylene, mixed fibers of rayon and polyethylene terephthalate, or polyethylene terephthalate fibers. It was fixed to the inner surface of the cartridge case by fusing or adhesive. Since the cleaning sheet is single-layered, it has 1 characteristics against magnetic disks, such as not damaging magnetic disks and excellent cleaning performance for magnetic disks, and adhesion characteristics to cartridge cases (adhesiveness, FA adhesion, etc.). It is necessary to have both characteristics.

It is not always possible to obtain the best characteristics for each characteristic, and therefore the cleaning sheet cannot function satisfactorily.

The purpose of the present invention is to eliminate such drawbacks of the prior art,
To provide a magnetic disk car 1 heritage having a cleaning sheet having excellent properties such as anti-media properties and adhesion properties.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention includes a cartridge case made of, for example, a flexible sheet material or a molded body of hard synthetic resin, and a flexible magnetic disk rotatably housed within the cartridge case. ,
The present invention is directed to a magnetic disk cartridge comprising a cleaning sheet thermally welded and supported on the inner surface of the cartridge case.

In the present invention, the cartridge case is made of thermoplastic synthetic resin, and the cleaning sheet has a media side nonwoven fabric layer made of a nonwoven fabric mainly made of acrylic fibers on the side facing the magnetic disk, and a media side nonwoven fabric layer on the side facing the magnetic disk, and a case-side nonwoven fabric layer that faces the inner surface and is made of a nonwoven fabric containing fibers that is embedded in the inner surface of the cartridge case, at least a portion of which is embedded in the inner surface of the cartridge case while retaining substantially the fiber form due to thermal fusion of the cleaning sheet to the cartridge case; It is characterized in that it is constructed from a sheet member having at least two layers.

[Actual example of invention]

Examples of the thermoplastic synthetic resin used in the cartridge case include polyvinyl chloride, A8S resin, polyacetal resin, polystyrene resin, etc.
A desired cartridge case can be formed by making it into a jacket shape as described later or by injection molding.

The above-mentioned magnetic disk is made of a base film made of polyester or polyimide, for example, and a magnetic thin film is formed on one or both sides of the base film by an appropriate method such as coating, vapor deposition, or sputtering, and has appropriate flexibility. There is.

The structure of the cleaning sheet thermally welded and supported on the inner surface of the cartridge case will be explained in detail using the first specific example.

1 to 6 are diagrams for explaining a magnetic disk cartridge according to a first embodiment of the present invention. FIG. 1 is a bottom view of the magnetic disk cartridge, and FIG. 2 is a developed view of the cartridge case and cleaning sheet of the magnetic disk cartridge.

FIG. 3 is an enlarged sectional view of the cleaning sheet.

Fig. 4 is a diagram for explaining the manufacturing process of the cleaning sheet, and Fig. 51! I is a plan view showing the state before the cleaning sheet is attached to the cartridge case; FIG. 6 is a partially enlarged sectional view for explaining the state of connection between the cartridge case and the fibers of the cleaning sheet.

The magnetic disk cartridge is composed of a cartridge case 1, a sheet-like flexible magnetic disk 2 rotatably housed within the cartridge case 1, and a cleaning sheet 3 fixed to the inner surface of the cartridge case 1.

As shown in FIG. 2, the cartridge case 1 is made of a rectangular case sheet material 4 made of, for example, hard polyvinyl chloride, and has three bonding edges 5a at one end.
5b and 5C are provided.

A rectangular cleaning sheet material 6 having approximately the same width is fixed to one side of the case sheet material 4.

The two square parts 4a, 4b and 6a, 6b of the case sheet material 4 and the cleaning sheet material 6 separated by the center folding line X (imaginary line) have the center hole 7 of the magnetic disk 2 (see FIG. 1). A rotation drive hole 8 with a larger diameter than the center hole to expose the peripheral part of the central hole, a magnetic head insertion port 9, a detection hole 10 for detecting the circumferential position of the magnetic disk 2 and tracking it correctly, and a magnetic Cutouts 11 and the like for detecting whether the disk cartridge is on side A or side B are formed at symmetrical positions.

As shown in the figure, after placing the cleaning sheet material 6 on the case sheet material 4, spot welding 12 is performed over almost the entire surface of the cleaning sheet material 6, and the rotation drive hole 8 and the magnetic head Insertion port 9. By linear welding 13 around the detection hole 10 and the notch 11, the cleaning sheet 1-material 6 is fixed to the case sheet material 4 without impairing its flexibility and elasticity. In this case, the cleaning sheet material 6 does not necessarily need to be spot welded 12 over the entire surface;
It is sufficient if the case sheet material 4 is fixed to such an extent that it does not easily separate from the case sheet material 4.

After that, fold the cleaning sheet material 6 in half from the center fold # &
Of the bonding edges 5a, 5b, 5c provided on the side, the bonding edges 5a, 5e facing each other are folded over the outside of the other square portion 4a, and as shown in FIG. By partially heat welding 14 as shown in , a bag-like body with one side open is made.

A magnetic disk 2 punched from a sheet-like raw material is inserted into this bag-like body, and then the remaining bonding edge 5b is folded over the outside of the square portion 4a and heat-fused 14. Finish assembling the magnetic disk cartridge.

The cleaning sheet 3 is as shown in FIG.

It has multiple layers of two or more layers. Next, the structure of this cleaning sheet 3 will be explained using FIGS. 3 to 6.

31st! Cleaning sheet 2 as shown in I
are a media side nonwoven fabric layer 15 facing the magnetic disk 2 and a case side nonwoven fabric layer I facing the cartridge case l.
G, its media side nonwoven fabric layer 15 and case side nonwoven fabric layer 1
6 is provided.

The media side nonwoven fabric layer 15 is composed of acrylic fiber alone. Acrylic fiber is a synthetic fiber containing approximately 85% or more acrylonitrile.

Acrylic acid ester, vinyl acetate, styrene sulfonic acid, etc. are copolymerized to improve the abrasion strength and dyeability. Among synthetic fibers, it is most similar to wool and has excellent flexibility with a soft touch. Acrylic fiber (
Stable) has a tensile strength of approximately 2.5 to 5.0 g/D, an elongation rate of approximately 25 to 50%, an elongation modulus (at 3% elongation) of approximately 90 to 95%, and a specific gravity of approximately 1.14. ~1,17. The acrylic fiber used has an Is degree of about 1 to 6 deniers.

In this example, the media side nonwoven fabric layer 15 was composed of acrylic fibers alone in order to fully exhibit the excellent media resistance properties of acrylic fibers, but the present invention is not limited to this. It is also possible to mix up to 50% of other fibers such as polyethylene terephthalate, polypropylene, polyamide, rayon, etc. in order to improve the bonding strength with the fibers or to improve the surface lubricity.

The case-side nonwoven fabric layer 16 is composed of a mixed fiber layer of rayon fibers and polyethylene terephthalate fibers. The mixing ratio of rayon fibers and polyethylene terephthalate fibers (rayon/polyethylene terephthalate) is appropriately selected in the range of about 179 to 9/1, and particularly preferably in the range of 3/7 to 7/3. As the rayon fiber, viscose rayon, #1 ammonia rayon, acetate rayon, etc. may be used. The tensile strength of rayon fiber (stable) is approximately 2.5 to 3.1 g/
D. The elongation rate is about 16-22%, the elongation modulus (at 3% elongation) is about 55-80%, and the specific gravity is about 1.50-1.52.

On the other hand, polyethylene terephthalate fiber is a polyester fiber obtained by polycondensation of terephthalic acid or dimethyl terephthalate and ethylene glycol.

The tensile strength of polyethylene terephthalate fiber (stable) is approximately 4.7 to 6.5 degrees, the elongation rate is approximately 20 to 50%, the elongation modulus (at 3% elongation) is approximately 90 to 99%, and the specific gravity is approximately 1
．． It is 38.

In the present invention, at least the media side nonwoven fabric and the case side nonwoven fabric are required, and these two layers may be joined by a binder, but in particular, an intermediate layer made of a nonwoven fabric containing thermoplastic fibers is disposed between them. In some cases, this is preferable because the media side nonwoven fabric layer and the case side nonwoven fabric layer can be appropriately joined without impairing the excellent flexibility provided by the acrylic fibers of the media side nonwoven fabric layer.

For the intermediate layer 17, various thermoplastic fibers such as polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyamide, and polyvinyl chloride can be suitably used. In particular, as mentioned above, the media side nonwoven fabric layer 15
Since acrylic fiber is used for the case side nonwoven fabric layer 16 and polyethylene terephthalate fiber is used for the case side nonwoven fabric layer 16, the middle layer 1 is
7 is preferably composed of a mixed fiber layer of acrylic fibers and polyethylene terephthalate fibers.The mixing ratio of acrylic fibers and polyethylene terephthalate fibers (acrylic fibers/polyethylene terephthalate fibers) is, for example, l
The ratio is appropriately selected within the range of /9 to 9/1, and the range of 377 to 7/3 is particularly preferred.

The basis weight of the cleaning sheet 3 composed of each layer is not particularly limited, but is about 20 to 4.
0g/rr? is appropriate. Note that the basis weight here is a value obtained by measuring the weight of five samples each measuring 50×50 m and taking the average value thereof.

FIG. 4 is for explaining an example of manufacturing the cleaning sheet 3. As shown in the figure, there are a roll wrapped with a mixed fabric 18, a roll wrapped with a mixed fabric 19, and a roll wrapped with a single fabric 20.
Four rolls are arranged side by side: one roll wrapped with the single-sheet fabric 21 and four rolls wrapped with the single-sheet fabric 21.

The mixed fabric 18 is made of rayon fibers and polyethylene terephthalate fibers (rayon/polyethylene terephthalate=3/7), and becomes the case-side nonwoven fabric layer 16 described above. The mixed fabric 19 is made of polyethylene terephthalate fibers and acrylic fibers (polyethylene terephthalate/acrylic fibers = 575), and becomes the above-mentioned intermediate M17. Both of the paper fabrics 20 and 21 are made of nonwoven fabrics made of acrylic fibers, and these canvas fabrics 20 and 21 serve as the aforementioned media side nonwoven fabric layers 15a and 15b (see FIG. 3).

In the figure, 22 is a guide roller for feeding out the respective papers 18, 19, 20, and 21, and 23 is a wire mesh for conveying the stacked nonwoven fabrics. Said paper 18.19.20.
The thickness of each paper 21 is 50 (t m), and each paper 18, 19, 20, 21 is stacked one after another on a wire mesh 23.
then passes between heated rollers. This regulates the thickness to a predetermined thickness, and the polyethylene terephthalate fibers, which are thermoplastic fibers mixed in the case side nonwoven fabric layer 16 and the intermediate layer 17, shrink when heated and strengthen their entanglement with other fibers. At the same time, the surface of the Il miscellaneous material softens and melts. As a result, the media side nonwoven fabric layer 1
5, the case-side nonwoven fabric layer 16, and the intermediate layer 17 are integrally connected to form the cleaning sheet material 6.

In this embodiment, as shown in FIGS. 3 and 4,
The paper 20 constituted the first media side nonwoven fabric layer 15b, and the paper 21 constituted the second media side nonwoven fabric layer 15a. By forming the media-side nonwoven fabric layer 15 into a plurality of thin layers in this manner, there is an advantage that variations in the total thickness are reduced.

When the cleaning sheet material 6 is manufactured in this way, 1
Next, by passing it between rollers whose peripheral surface has been knurled (emboss processing), a large number of irregularities 23 are formed on the surface of the cleaning sheet material 6, as shown in FIG. In FIG. 2, the unevenness 23 is omitted in order to simplify the first drawing. The cleaning sheet material 6 constructed in this way is welded to the case sheet material 4 by spora 1 to welding 12 and linear welding 13 in the same manner as described above.

Car 1 - The polyvinyl chloride sheet constituting the ridge case 1 (case sheet material 4) softens at about 65 to 85°C, becomes plasticized at about 120 to 150°C, and begins to melt at 170°C. On the other hand, the rayon fibers in the case nonwoven fabric W116 do not soften or melt, but begin to decompose under heat at about 260 to 300°C. Therefore, as mentioned above, the cleaning sheet 3 (cleaning sheet material 6
) to the cartridge case l (case sheet material 4), as shown in FIG.
The rayon fibers 24 in the case-side nonwoven fabric layer 16 of the (cleaning sheet material 6) are embedded in the inner surface of the cartridge case 1 (case sheet material 4) while retaining their fiber form. Since the cross-sectional shape of the rayon fiber 24 is generally non-circular, this is the shape of the cartridge case l (
When embedded in the case sheet material 4), the cleaning sheet 3 is securely supported by the cartridge case 1.

Further, the buried rayon fibers 24 are entangled with other fibers in other parts or are thermally fused by the polyethylene terephthalate fibers, thereby ensuring that the cleaning sheet 3 is fixedly supported to the cartridge case 1.

In this first embodiment, the mixing ratio of fibers in the case side nonwoven fabric layer 16 was set to rayon fiber/polyethylene terephthalate fiber = 377, but by increasing the mixing ratio of rayon fiber,
For example, it is also possible to use rayon fiber/polyethylene terephthalate fiber=7/38 degrees. In addition, in the first embodiment, the mixing ratio of the fibers in the intermediate layer was set to 515 polyethylene terephthalate fibers/acrylic fibers, but the mixing ratio of polyethylene terephthalate fibers, which are directly involved in connecting the living room, was increased to 1, for example, polyethylene terephthalate fibers/acrylic fibers.
Acrylic fiber - 7/3T! It can also be A degree.

FIG. 7 is an enlarged sectional view of a cleaning sheet 3 according to a second embodiment of the present invention. In this embodiment, unlike the first embodiment, the media side nonwoven fabric layer 15 is a thick single layer. Further, the intermediate layer 17 may be made of polysalt f-hibinyl, for example.
It is composed of a thermoplastic synthetic resin film such as polyamide or polystyrene. In this figure, the middle layer 17
Although it is depicted as a layer having a uniform thickness, in reality it does not have a uniform thickness as shown in the drawing due to the plasticization and heat fusion of the intermediate Mj and +7.

In the above embodiment, as shown in FIG. 5, a large number of embossments are formed on the surface by knurling to provide smooth sliding contact with the magnetic disk and good leaning ability. For the cleaning sheet material 6.

In addition to such embossing, cleaning sheets 1~
During production, a large number of minute holes may be formed by spraying a water jet to achieve the same effect as the embossing process.

Further, as shown in FIGS. 3 and 7, the thickness of the media side nonwoven fabric layer 15 mainly made of acrylic fibers is approximately twice as thick as that of the other case side nonwoven fabric layer 16 and the intermediate layer 17. By that.

The flexibility and cleaning properties unique to acrylic fibers can be fully demonstrated.

In the above Examples, the cleaning sheet material was a sheet composed only of a nonwoven fabric made of acrylic fiber alone (comparative example), and a nonwoven fabric formed by mixing rayon fiber and polypropylene fiber in a weight ratio of 8:2. (conventional example 1), and a sheet made of polyethylene terephthalate fiber alone (conventional example 1). A magnetic disk cartridge was produced using a sheet made only of cloth (Conventional Example 2).

The above examples, comparative examples, and conventional examples 1. Regarding Conventional Example 2, the cutting properties, cleaning properties, magnetic disk abrasion properties, lint properties, and welding properties of the cleaning sheet were tested using the following methods.

A. Cutting properties Each of the cleaning sheet materials 6 of Examples, Comparative Examples, Conventional Example 1, and Conventional Example 2 was thermally welded to the case sheet material 4 made of hard polyvinyl chloride as in the previous example.

Thereafter, the rotary drive hole 8 and the magnetic head insertion port 9 are punched together with the case sheet material 4 at a punching speed of 120 times per minute, and at this time, fuzz is generated at the cut ends of the rotary drive hole 8 and the magnetic head insertion port 9. 1! I guessed it.

B. Cleanability Example, Comparative Example, The magnetic disk cartridge using each of the cleaning sheet materials 6 of Conventional Example 1 and Conventional Example 2 is installed in a recording/reproducing device, the magnetic disk 2 is rotated within the cartridge case 1, and the magnetic disk 2 is rotated in the cartridge case 1. Deliberately put a small amount of iron powder into the cartridge case l from the spatula insertion port 9, and leave it for 10 minutes.
After rotating, the cartridge case 7 was opened and the adhesion of iron powder to the inside of the cleaning sheet 3 was examined.

C0 Magnetic Disk Scratch Resistance When each sample was connected for one period at room temperature and the magnetic disk was rotated, the occurrence of scratches caused by the cleaning sheet on the magnetic disk was observed.

D. Lint characteristics A predetermined cleaning sheet for each sample was immersed in L/ON solvent, and ultrasonic imaging was applied for 10 minutes.1. A test was conducted to see if the orange cloth fell off the cleaning sheet.

E. Weldability For each sample, cleaning sheet materials 6 are spot welded and fixed on the case sheet material 1-4 at 7 m intervals. A part of this cleaning sheet material 6 is shaped into a belt with a width of about 51 mm. +1 is attached, and the other end is case sheet material 4
7. Next, by placing the case sheet material 4 upward and the cleaning sheet material 6 facing F, the part peeled off from the case sheet material 4 hangs down from the case sheet material 4, A weight is applied to the hanging portion in the direction in which the cleaning sheet material 6 separates from the case sheet material 1-4, and the amount of load is gradually increased so that the fixed portion (welded portion) of the cleaning sheet material 6 is removed from the case. The amount of load (g) at which the sheet material 4 started to peel off was measured.

The results of each of these tests are shown in the table below.

As is clear from the test results, the one according to the embodiment of the present invention is superior in cutting performance, cleaning performance, magnetic disk scratch resistance, lint property, and welding performance compared to the comparative example and the conventional example. I understand that.

8 to 12 are for explaining a magnetic disk cartridge according to a third embodiment of the present invention, and FIG. 8 is an exploded perspective view of the disk cartridge, and FIG.
10 is a bottom view showing the state in which the cleaning sheet is attached to the upper case, FIG. 10 is a plan view showing the state in which cleaning sheets 1 to 1 are attached to the lower case, and FIG. 11 is a view showing the state in which this magnetic disk cartridge is used. FIG. 12 is an enlarged sectional view of the vicinity of the magnetic I/rad inlet, and FIG. 12 is an enlarged sectional view of the vicinity of the elastic piece of this magnetic disk cartridge.

The magnetic disk cartridge is stored in the cartridge case 26.
, a magnetic disk 27 rotatably housed therein, and a shutter 28 slidably supported by a cartridge case 26 .

The cartridge case 26 includes an upper case 26a and a lower case 2.
6b, and these are molded from hard resin such as ABS resin.

- The upper case 26b has an opening 29 for inserting the rotational drive shaft, and a rectangular head insertion opening 30 is provided near the opening 29. Similarly to # and J, the upper case 26a has a head insertion opening 30. It is provided. As shown in FIG. 8, near the front of the upper case 26a and the lower case 26b,
Four slightly lowered portions 31 are formed to restrict the sliding range of the shutter 28, and the magnetic head insertion opening 30 is provided at an intermediate position of the recessed portions 31.

As shown in FIG. 9, there are counterbore-shaped recesses 42 on the inner surface of the upper case 26a and on both left and right sides of the magnetic head insertion slot 30.
．． 42 are formed respectively.

The vertical width Wl of the recess 42 is approximately equal to the longitudinal width (vertical @) W2 of the magnetic head insertion port 30, and the horizontal MW of the recess 42
3 is regulated to be at least 0.3 times the cap (width) W4 in the direction orthogonal to the longitudinal direction of the magnetic head insertion port 30, preferably in the range of 0.5 to 1.5 times.

On the upstream side of the magnetic I/rad inlet 30 of the upper case 2Ga in the disk rotational direction, there are provided a large number of linearly extending protrusions 43, of which two on both sides are slightly higher than the inner protrusions 43. .

An arc-shaped regulating rib 44 for regulating the storage position of the magnetic disk 27 is protruded from the inner surface of the upper case 26a, and a part of the regulating rib 44 passes through the end of the recess 42.
It also serves as a reinforcement for the surrounding area.

As shown in FIG. 9, inside the regulating rib 44, there is a C.
Letter-shaped cleaning sheets 1 to 45 are inserted. The width W5 of the opening 46 provided in the cleaning sheet 45 at a position corresponding to the magnetic head insertion opening 30 is designed to be slightly larger than the width W4 of the magnetic head insertion opening 30. By placing the cleaning sheet 45 on the inner surface of the upper case 26a, the recess 42 and the protrusion 43 are also covered, and the peripheral portion of the cleaning sheet 45 is thermally welded to the upper case 26a. As mentioned above, the recess 4 of the upper case 26a
2 has a sufficient width, so that the edge of the opening 46 in the cleaning sheet 45 forms the recess 4 as shown in FIG.
2 can be thermally welded 47.

As shown in FIG. 1O, a protruding support portion 48 and a protruding protrusion 49 for preventing sticking are provided on the inner surface of the lower case 2bb at a position substantially facing the protrusion 43 of the upper case 26a. As shown in FIGS. 10 and 12, a bottom portion 51 of an elastic piece 50 formed by bending the plastic sheet 1 to
is fixed to the inner surface of the lower case 26b and near the support portion 48 by an appropriate means such as adhesive or heat fusion. The free end 52 of the elastic piece 50 is supported by the support portion 48 to maintain its inclined state.

A regulating rib 44 is also protruded from the inner surface of the lower case 26b, and a cleaning sheet 45 is disposed inside the regulating rib 44. The width W5 of the opening 46 provided in the cleaning sheet 45 at a position corresponding to the magnetic head insertion opening 30 is designed to be slightly larger than the width W5 of the magnetic head insertion opening 30. As shown in FIG. 10, by attaching the cleaning sheet 45 to the inside of the lower case 26h, the elastic piece 50 is covered, and the peripheral portion of the cleaning sheet 45 is heated to the lower case 26b. Thermal welding 47 is omitted near the shore 50.

When a magnetic disk cartridge is assembled by combining upper game 7, 2tll+a and f case 26b.

As shown in FIG. 12, the lower case 26 is
The second cleaning sheet 15 of b is partially lifted, and the lifting is slightly pushed up by the protrusion 43 provided on the upper case 26a, so that the magnetic disk 27 is placed on top of the cleaning sheet 45 of d. .45. As the magnetic disk 27 rotates, the cleaning sheet 45 cleans the surface of the disk.

Number 11 is a diagram showing the state of use of the magnetic disk cartridge, and 53 in the diagram is a magnetic disk cartridge. j Vine.

In this example as well, as in the case where the case sheet made of 4ILr vinyl chloride was used, the cutting properties, cleaning properties, etc. It has been confirmed that the magnetic tape has excellent scratch resistance, lint properties, and welding properties.

〔Effect of the invention〕

As described above, in the present invention, the layer of the cleaning sheet on the media side facing the magnetic disk is mainly composed of acrylic electrolyte and a nonwoven fabric layer. This acrylic fiber has excellent flexibility among synthetic fibers, and has a high cleaning effect without scratching the surface of a rotating magnetic disk. Because of the good quality of the magnetic tape, the magnetic tape (for example, when manufacturing a short cartridge, there is no possibility that part of the fibers will protrude inward from around the magnetic/rad insertion opening or rotational drive hole. Especially magnetic If the fibers protrude toward the head insertion direction, errors may occur during recording or playback due to the L/L, but as mentioned above, acrylic fibers have excellent click and rg properties. Therefore, there is no error caused by the t-reading of the fibers.

On the other hand, the case side non-woven ft in the cleaning seam E.
Some of the fibers in the i-layer retain the form of fibers and are buried in the inner surface of the cartridge case by heat melting.Therefore, the cartridge case and its fibers, in other words, the cartridge The connection between the case and cleaning sheet is strong.

When the magnetic disk cartridge is in use, a torsional force is applied to the cleaning sheet due to the sliding contact of the magnetic disk.
However, there is no need to worry about the cleaning sheet peeling off from the cartridge case.

From the above, we can conclude that Sentence 4 Media characteristics and Car 1~Rituji/r・-Set characteristics such as +'! :1':
If you have an excellent no-clean sheet, you can also use a disc cartridge.

[Brief explanation of drawings]

2gt diagram and Figure 6 are F! of the present invention. This is for explaining the magnetic disk cartridge according to the eleventh embodiment,
Figure 1 is a bottom view of the magnetic disk, hook 1, and ridge.
The figure is an exploded view of the ridge case and cleaning sheet for the car 1 of the magnetic disk cartridge, FIG. 3 is an enlarged sectional view of the cleaning sheet, and FIG. 4 is an explanatory diagram for explaining the manufacturing process of the cleaning sheet 1. , FIG. 5 is a plan view showing the state before the cleaning sheet is attached to the cartridge case, FIG. 6 is a partially enlarged sectional view for explaining the state of connection between the cartridge case and the fibers of the cleaning sheet, and FIG. FIG. 8 is an exploded perspective view of a magnetic disk cartridge according to a third embodiment of the present invention, and FIG. 9 is an enlarged sectional view of a cleaning sheet according to a second embodiment of the present invention. Fig. 10 is a plan view of the lower case with the cleaning sheet attached, and Fig. 11 is an enlarged view of the area near the magnetic head insertion slot showing how this magnetic disk cartridge is used. 12 is an enlarged sectional view of the vicinity of the elastic piece of this magnetic disk cartridge. 1...Cartridge case, 2...1
iti disk, 3...Cleaning sheet,
12・・・・・・Spot welding, 13゛−・−・−
Linear welding, 15.15a, 15b... Media side nonwoven fabric layer, 16... Case side nonwoven fabric layer, 17.
...Middle layer, 23...Irregularities, 24...
...Rayon fiber, 25...Through hole, 26...
...Car 1-ridge case, 26a...upper case, 26h...lower '7-7, . 27...
...Magnetic disk, 45...Cleaning sea)
-,47...Heat 1 adhesion Figure 1 ~ 4 ・N-V'+ Figure 3 Figure 7 Figure 4 and J Figure 6 Figure 9 Figure 1O Figure 11 Figure 5 I

Claims (8)

[Claims] (1) A magnetic disk cartridge comprising a cartridge case, a magnetic disk rotatably housed within the cartridge case, and a cleaning sheet heat-welded and supported on the inner surface of the cartridge case, wherein the cartridge case is made of thermoplastic material. Composed of synthetic resin,
The cleaning sheet has at least a media side nonwoven fabric layer made of a nonwoven fabric mainly composed of acrylic fibers on the side facing the magnetic disk, and a media side nonwoven fabric layer that faces the inner surface of the cartridge case, and the cleaning sheet is thermally fused to the cartridge case. and a case-side nonwoven fabric layer made of a nonwoven fabric containing fibers, which is embedded on the inner surface side of the cartridge case while at least a portion thereof substantially retains the form of fibers. cartridge. (2) A magnetic disk cartridge according to claim (1), wherein the media-side nonwoven fabric layer is composed of acrylic fibers alone. (3) A magnetic disk cartridge according to claim (1), wherein the cartridge case is made of polyvinyl chloride, and the case-side nonwoven fabric layer contains rayon fibers. (4) A magnetic device according to claim (1), characterized in that an intermediate layer made of a nonwoven fabric containing thermoplastic fibers is disposed between the media side nonwoven fabric layer and the case side nonwoven fabric layer. disc cartridge. (5) Claim (4), wherein the media side nonwoven fabric layer is a fiber layer consisting of acrylic fibers alone;
A magnetic disk cartridge characterized in that the intermediate layer is composed of a mixed fiber layer of acrylic fibers and polyethylene terephthalate fibers, and the case side nonwoven fabric layer is composed of a mixed fiber layer of polyethylene terephthalate fibers and rayon fibers. (6) A magnetic disk cartridge according to claim (1), wherein the media side nonwoven fabric layer is thicker than the case side nonwoven fabric layer. (7) A magnetic disk according to claim (1) or (5), characterized in that a large number of concavities and convexities are formed by embossing on the surface of the cleaning sheet that faces the magnetic disk. cartridge. (8) A magnetic disk cartridge according to claim (1) or (5), wherein the acrylic fiber has a fineness of 1 to 6 deniers.