JPH0519910Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a magnetic tape cassette, and more particularly to a magnetic tape cassette having a cassette body on which a protective film layer made of a polymeric material or the like is formed on the surface. It is something.

(Prior Art) A magnetic tape cassette is constructed by holding a winding hub on which a magnetic tape is wound inside a cassette body. This cassette body is usually made by injection molding of plastic material, etc. After this molding, paper or the like with a predetermined design is pasted on the outer surface of the body for the purpose of obtaining a design effect. A predetermined design can be printed directly.

However, this method requires a process of injection molding the body and a process of pasting paper, etc. on the outer surface of the body or a printing process, so it is difficult to print a predetermined design on the outer surface of the body at the same time as injection molding. A method called transfer molding was devised to do this. This transfer molding will be briefly explained below with reference to FIG. 4. Injection molding is performed using two molds 1 and 2, and when both molds 1 and 2 are put together, the shape of the cassette half formed by the recesses 3 and 4 of both molds 1 and 2 is formed. This is done by injecting a molten material such as a plastic material into a corresponding space from a gate 1a through an injection hole 1b. When performing transfer molding, both molds 1 and 2 are
A transfer film 5 provided with an ink layer having a predetermined design is placed between the molds 1 and 2 with the molds 1 and 2 separated, and the molds 1 and 2 are placed between the molds 1 and 2 with the transfer film 5 in between.
Match 2. After that, a predetermined amount of molten material is injected from the gate 1a, and the transfer film 5 is transferred to the mold 2.
The space inside the mold formed by the recesses 3 and 4 is filled with the molten material by pressing it against the recess 4 of the mold. At this time, the transfer film 5 is made by laminating a release layer 7, an ink layer 8, and an adhesive layer 9 in this order on a base film 6, as shown in FIG. Upon contact with the molten material, the adhesive layer 9 bonds the ink layer 8 to the injection material or surface of the cassette, and the release layer 7 allows the base film 6 to be easily peeled off from the cassette surface. Therefore, after this,
When the material filled in the mold space cools and solidifies, the body is taken out and the base film 6 is peeled off, leaving the ink layer 8 on the transfer film 5 in a transferred state on the surface of the body.

In this way, when an ink layer is transferred to the surface of the cassette body, this ink layer is exposed to the outside on the cassette surface, and the film strength of the ink layer formed by this transfer molding is not very strong, so it may be The ink layer may be rubbed or peeled off.

Furthermore, as mentioned above, if the cassette body is made by injection molding of plastic material, etc., it is easy to manufacture and mass-produce. Therefore, there is a problem in that the impact strength is relatively low, and the body is easily damaged if the magnetic tape cassette is accidentally dropped on the floor.

For this reason, the present applicant conducted injection molding similar to the above transfer molding using a protective film from which the release layer 7 of the transfer film 5 used in the above transfer molding was removed, and applied this protective film to the surface of the cassette body. We proposed a cassette body that is integrally joined to form a protective film layer. In this way, since the ink layer is located on the inner surface of the protective film layer and covered by the base film forming the protective film layer, the problem of the ink layer peeling off during use of the cassette will not occur. Furthermore, if this protective film layer covers the ridge of the cassette body, even if the injection molded material has low impact strength and is easily damaged, the protective film layer that covers it from the outside increases the impact strength. This also reduces the problem of damage to the cassette body.

(Problem that the invention aims to solve) On the other hand, when using a magnetic tape cassette, it is common to provide a designated writable memo field on the surface of the cassette for memoing the contents recorded on the magnetic tape cassette. . In conventional magnetic tape cassettes, when paper with a predetermined design is attached to the surface of the cassette body, a memo field is provided on this paper, and when a predetermined ink layer is printed on the surface of the cassette body, a memo field is provided on the paper. Labels for notes, etc. began to be affixed to the surface of the cassette body. However, when a protective film layer is provided on the surface of the cassette body at the same time as injection molding as described above, if the outer surface of the protective film layer is previously subjected to a writable treatment such as matte treatment,
It is convenient to be able to write notes on the cassette surface without having to affix a label or the like to the cassette surface later.

(Means for Solving the Problems) Therefore, in the present invention, in a magnetic tape cassette having a cassette body with a protective film layer integrally bonded to the surface at the same time as injection molding, the protective film layer is The magnetic tape cassette of the present invention is constructed as follows.

The cassette body of this magnetic tape cassette is made by injection molding of plastic material, etc., and the surface of the cassette body has a protective film layer placed in the injection mold and integrally bonded at the same time as the injection molding. The outer surface of this protective film layer is provided with a writable treatment layer, such as a matte treatment layer, which is previously formed before injection molding.

(Function) By using the magnetic tape cassette constructed as described above, it is possible to write notes, etc. directly on the surface of the protective film layer by the writable processing layer applied to the protective film layer of the cassette body. This is convenient because there is no need to attach a label for notes or the like to the outside of the cassette as in the past.

(Embodiments) Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a magnetic tape cassette according to the present invention. A pair of winding hubs 21, 21 are rotatably built-in and held in the hub parts 15b, 15b of the lower half 15 (not shown).
and a magnetic tape 22 wound around this winding hub. The upper half 11 and the lower half 15 are injection molded separately, but as shown in FIG. 2, which shows a cross section along the arrow - in FIG. Base body 13, 17 made of material
and protective film layers 12 and 16 that cover the surfaces of the base bodies 13 and 17. In addition, at this time, the protective film layers 12 and 16 are attached to each half 11,
From the viewpoint of strengthening the cassette body, it is desirable that the cassette body be formed so as to cover at least the ridges 11a and 15a of the cassette body.

This protective film layer 12, 16 is
When injection molding 1 and 15, this protective film layer 1 is formed at the same time as this injection molding.
The formation of 2 and 16 will be explained. This cassette body is manufactured using the molds 1 and 2 shown in FIG. 4, and injection molding of the upper half 11 will be explained as an example. FIG. 4 shows a case where injection molding is performed with the transfer film 5 sandwiched between the molds 1 and 2, but in the case of this embodiment, the transfer film 5
A protective film layer 12 is sandwiched instead. As shown in FIG. 3, this protective film layer 12 includes an ink layer 12b which has a design representing the external appearance of a magnetic tape cassette, etc. on the inner surface side of the base film 12a (the side that contacts the base body 13), and an ink layer 12b that protects the base film 12a. An adhesive layer 12c for bonding the film layer 12 to the base body 13 is laminated in this order, and a writable processing layer 12d is provided on the outer surface of the base film 12a. The writable treated layer 12d is formed by matting the outer surface of the base film 12a or by providing a writable ink layer on the outer surface. Note that, as the material for this base film 12a, a polymeric material such as polyethylene, polyethylene terephthalate, polypropylene, triacetate cellulose, etc. is used.

Such a protective film layer 12 is continuously formed in a band shape, and the protective film layer 12 is sent downward in the figure so that its inner surface faces the mold 1 having the gate 1a, and the ink layer 12a is into position. Next, the protective film layer 12 is sandwiched between the two molds 1 and 2, and then the injection material is injected and supplied from the gate 1a through the injection hole 1b into the space formed by the recesses 3 and 4. In this way, both the recesses 3 and 4 are held in a state where the protective film layer 12 is pressed against the recess 4 of the mold 2.
The space formed by the injection material is filled with the injection material. At this time, this injection material forms the protective film layer 1.
The surface of the base body 13 where the injection material cools and hardens while the antistatic layer 12d, the base film 12a, and the ink layer 12b, which form the protective film layer 12, are in contact with the adhesive 12c of No. 2 and are integrated with the adhesive. is joined to.

When the cassette body is manufactured in this way, a protective film layer 1 is applied to the surface by injection molding.
Since a writable processing layer 12d is provided on the outer surface of this protective film layer 12, recorded contents can be easily made on the cassette surface without the need to affix a label or the like to the surface. You can freely write notes, etc.
Note that the writable processing layer 12d only needs to include at least the label area of a conventional cassette, that is, the portion surrounded by the broken line A in FIG. 1, and does not necessarily have to be writable on the entire surface. moreover,
If an ink layer representing the exterior design of the cassette is previously provided on the inner surface of the protective film layer 12, it becomes possible to simultaneously display the design on the surface of the cassette by injection molding.
However, in this case, the base film 12a must be transparent or semitransparent, and it goes without saying that this ink layer may or may not be provided.

(Effects of the invention) As explained above, according to the invention, the cassette body of a magnetic tape cassette is made by injection molding of a plastic material, etc., and the surface of the cassette body is covered with a protective film that is integrally bonded at the same time as the injection molding. Since a writable treatment layer is provided on the surface of the protective film layer, it is easy to manufacture a cassette body having a protective film layer on the surface, and a magnetic tape cassette using this cassette body can be manufactured. The cassette body is very convenient because it allows you to write notes such as recording contents directly on the writable surface of the cassette body without attaching a label or the like to the outside surface.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a magnetic tape cassette according to the present invention, FIG. 2 is a sectional view of the magnetic tape cassette taken along the arrow - in FIG. 4 is a cross-sectional view of the protective film layer to be bonded and formed; FIG. 4 is a cross-sectional view showing an injection mold used for transfer molding of a conventional cassette half for a magnetic tape cassette;
The figure is a sectional view showing the transfer film for transfer molding. 1, 2...Mold, 5...Transfer film, 11...
...Top half, 15...Bottom half, 11a, 15a
1...Ridge, 12, 16...Protective film layer, 1
2d...Writable processing layer. 13, 17...Base body.

Claims (1)

[Scope of Claim for Utility Model Registration] 1) A magnetic tape cassette consisting of a magnetic tape, a pair of winding hubs, and a cassette body rotatably holding the winding hub with the magnetic tape wound therein, A cassette body is made by injection molding of a plastic material or the like, and a protective film layer is formed on the surface of the cassette body, which is placed in an injection mold and integrally bonded at the same time as the injection molding, A magnetic tape cassette, wherein the protective film layer has a writable treatment layer provided on its outer surface before the injection molding. 2) The magnetic tape according to claim 1, wherein the protective film layer has, on its inner surface, an ink layer representing the design of the outer surface of the cassette, which is provided before the injection molding. Cassette. 3) Utility model registration claim 1, characterized in that the writable treatment layer is a matte treatment layer.
The magnetic tape cassette described in Section 1.