JPH09300351A - Composite molded object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To take full advantage of the high mechanical strength possessed by the base material of a magnetic card by filling a resin binder with card fine pieces obtained by cutting or grinding used cards containing a plastic oriented sheet as a base material in a specific ratio to form a composite molded object. SOLUTION: A used card using a sheet of polyethylene terephthalate as a base material is cut or ground to be reutilized as fine pieces. A resin is filled with these fine pieces. As a resin becoming a binder, various ones can be used and the so-called adhesive or adhesive resin can be pref. used. The filling amt. of fine pieces of the used resin card is pref. a range of 6/1-2/1 based on a wt. ratio of fine piece/resin. By this constitution, the deterioration of characteristics caused by heat history is generated and the orientation structure possessed by the plastic oriented sheet is put to practical use in the obtained molded object and high strength and high rigidity are applied to the molded object.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for reusing a variety of used cards, particularly magnetic cards, to form a composite molded article having excellent strength.

[0002]

2. Description of the Related Art In recent years, the amount of magnetic cards used as prepaid cards has dramatically increased. For example, prepaid cards for telephone calls known as telephone card names, boarding fees, and pachinko Prepaid cards such as game fees, ski lift fees, parking fees, etc. are used. Most of these magnetic cards are used up within a day or a few months, but if discarded and scattered after use, the environment will be damaged, and the disposal / reuse of used cards is an important issue.

Generally, the recycling of plastic molded products is
Different materials are separated from the plastic molded product and crushed, or the different materials are separated after crushing, and the remaining plastic material is granulated, and remolded into another molded product by melt molding such as melt extrusion and re-formed. It is done by using it.

A magnetic card is generally made of a biaxially stretched sheet of polyethylene terephthalate (hereinafter sometimes abbreviated as PET) as a base material and coated with a magnetic layer. Requires the magnetic layer to be removed by grinding or the like to separate the PET sheet, and the PET sheet needs to be re-molded through steps such as crushing, drying, foreign matter removal, and granulation, which results in considerable cost. . In addition, it is difficult to avoid deterioration of properties of the obtained remolded product due to thermal history, and it is difficult to manufacture a remolded product having high characteristics. Further, in such a method, the high mechanical strength of the base material of the magnetic card is not utilized at all for the reshaped product.

[0005]

DISCLOSURE OF THE INVENTION The present invention overturns the conventional wisdom that a conventional plastic molded product is crushed, melted and reused, and the mechanical properties of cards such as magnetic cards having a plastic oriented sheet as a base material have The above-mentioned problems were solved all at once by making the best use of the above as a composite molded body.

[0006] That is, the gist of the present invention is to cut a card strip, which is a used card having a plastic-oriented sheet as a base material, into cut or crushed pieces, and a resin binder is used in a ratio of 6: 1 to 6: 1.
It is in a composite molded body formed by filling at a ratio (weight) of 2: 1.

According to the present invention, a molded product having high strength, particularly high rigidity can be obtained by taking advantage of the high strength of the plastic oriented sheet base material of the card. Further, it is not always necessary to separate the magnetic material from the magnetic card or the like, and the magnetic material can be reused as it is.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The magnetic card, which is the main object of the present invention, uses a sheet of polyethylene terephthalate (PET) that is biaxially stretched and heat-fixed as a base material, and is highly molecularly oriented. As the PET sheet, a sheet having a thickness of 188 μm is often used. A magnetic layer is formed on one surface (back surface), a protective layer is formed on the magnetic layer, and a printing layer and a protective layer are formed on the other surface (front surface).

The used card can be separated from the magnetic material if desired, but can also be used without separation by only performing a simple cleaning / drying process if necessary.
Cards are cut or crushed into small pieces for reuse. This is mainly because the strips are more likely to be uniformly distributed in the resin that serves as the binder, and the molding process is also easier.

If the size for cutting or crushing is too fine, the strength of the base material itself is not utilized and the reinforcing effect is small, and if it is large, the plane direction arrangement as described below is easily achieved but the molding process is difficult. , It may be set depending on the balance of both. That is, the diameter is 100 μm
The object can be achieved by reusing in a plate-like form in which the molecular orientation can be substantially maintained and the layers can be arranged in multiple layers along the plane, avoiding the following fine pulverization, melting and dissolution.

In one example, the card strip has a length (width)
/ It can be used in the form of a plate having a thickness ratio (aspect ratio) of 5 or more. The card may be cut into a certain shape with a blade, or may be crushed into an irregular shape by crushing.

Then, the strips of the used card are filled with resin. Various kinds of resins can be used as the binder resin, and resins called so-called adhesives and adhesive resins can be preferably used, but other ordinary resins can also be used.

For example, a thermoplastic resin (adhesive) such as a thermoplastic polyester resin, an acrylic resin or an acid-modified polyolefin resin; a thermosetting resin (adhesive) such as an unsaturated polyester resin, a urethane resin or an epoxy resin is used. be able to. It may also be a room temperature curable adhesive.

The filling amount of the used card strips is
The range of 6/1 to 2/1 by weight of the resin is preferable. 6
If the number of strips is larger than / 1, the strips are insufficiently integrated and are likely to peel or crack. If the number of fine pieces is less than 2/1, the effect of improving the strength of the obtained molded article is small,
Also, from the viewpoint of reusing used cards, it is preferable that the amount of strips filled is large.

The method of molding the mixture of the strips and the resin binder into a predetermined shape is not particularly limited, but in order to obtain a highly rigid molded body, most of the strips are arranged substantially along the surface direction of the molded body. (Arranged so that the surface of the strip and the surface of the molded body are substantially aligned). For that purpose, it is preferable to use a molding method in which the resin binder flows and the strips are aligned in a substantially constant direction due to the flow. For example, a mixture with the resin binder is passed through a nipro roll or a pair of belts, a slit, a blade, or the like through a plate shape. Can be It is also possible to mix the strips with a resin binder and fill them in a mold and pressurize them to form a plate, and in that case too, most of them will flow due to the resin flow during filling into the molds and / or during pressurization. The strips are arranged substantially along the plane direction of the plate-shaped body.

When the binder resin is a thermoplastic resin, it is molded at a temperature lower than the melting temperature of the plastic base material and heated to a temperature at which the resin binder flows. When the resin binder is a thermosetting resin, the resin binder is thermoset at a temperature lower than the melting temperature of the plastic base material. If it is a room temperature curing type adhesive, heating is not particularly required. In any case, by setting the temperature to a temperature lower than the melting temperature of the plastic base material, the oriented structure of the plastic base material is maintained even in the molded body, so that the plate-like body having high tensile strength, elastic modulus, etc. Is obtained. Generally, since PET has a melting point of 260 ° C. or higher, it can be practically molded in a wide temperature range from room temperature to 200 ° C.

The molded product of the present invention has great utility mainly as a plate-shaped product. The thickness of the plate-like body is not particularly limited and can be arbitrarily set, but for example, the plate-like body can be formed in the range of about 1 mm to about 5 cm.

In particular, it has been difficult in the past to stretch and orient a thick plate having a thickness of 5 mm or more, but the present invention makes it possible to obtain a plate-like body having a stretched and oriented structure without limitation to the thickness. That is a big feature.

A sheet of polyvinyl chloride, PET or the like can be adhered to one or both sides of the molded article of the present invention to improve the appearance, depending on the application, and those sheets can be subjected to, for example, wood grain printing. Good. Alternatively, a metallic material such as a steel plate or an aluminum plate may be attached to give a metallic appearance. The surface can also be painted. Further, the resin binder may contain reinforcing / filling components such as glass fiber and granular filler to further improve the overall rigidity.

The thus obtained composite molded article of the present invention can be used in various applications such as civil engineering construction materials, horticultural materials, and top plates for furniture.

[0021]

According to the present invention, when a used magnetic card is reused, a crushed product is not melted and re-formed, so that it is possible to obtain not only characteristic deterioration due to thermal history but also obtained. The orientation structure of the plastic orientation sheet base material is utilized in the molded article, so that the molded article has high strength and high rigidity. By using the card in strips, molding becomes easy. Moreover, since the magnetic material is not always required to be separated during reproduction, the reproduction process itself can be greatly simplified.

Claims (1)

[Claims] 1. A card strip obtained by cutting or crushing used cards having a plastic orientation sheet as a base material,
A composite molded body formed by filling the resin binder at a ratio (weight) of 6: 1 to 2: 1.