JP2002103429A - Plastic bottle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate reproduction of a plastic bottle by using plastic materials of the same kind thermally fusible to each other and to use reproduced plastics in the outer layer of a bottle main body not only to reduce cost but also to apply rigidity being mechanical characteristics to the bottle. SOLUTION: In a sanitary plastic bottle having excellent rigidity, the inner layer of the main body part of the bottle comprises a new plastic material and the outer layer thereof comprises reproduced plastic materials same to the new plastic material in kind and thermally fusible to each other and the mouth part or/and neck part of the bottle comprise the new plastic material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic bottle. Plastic bottle.

[0002]

2. Description of the Related Art Recently, plastic bottles have become widespread even in ordinary households because they do not have to worry about being broken even when dropped like glass bottles, and are lightweight and convenient for transportation.
Conventionally, plastic bottles have been discarded after use and landfilled as bulky garbage.However, environmental problems have arisen, and these waste plastic bottles have recently undergone crushing, washing, dewatering and drying processes. Attention has been focused on pelletizing and reusing.

[0003] Plastic bottles contain fruit juice, milk,
Widely used in the field of medical devices such as tea, mineral water, beverages such as beer, foodstuffs, seasonings such as soy sauce, and infusions, etc. May be used. In the case of a bottle made of a multi-layered material of different materials, from the viewpoint of bottle recycling, it is impossible to separate the materials, and there is a great problem in saving and environment.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to solve the problems of the conventional plastic bottles, that is, the cost of the bottles made of multilayer materials of different materials used in applications requiring hygiene and rigidity. The invention has been made in order to solve the environmental problem, and it is easy to recycle a plastic bottle by using the same kind of plastic materials that can be thermally welded to each other. Is used to reduce the cost and to impart rigidity, which is a mechanical property, to the bottle.

[0005]

That is, according to the present invention, the inner layer of the main body and the neck portion is made of a new plastic, the outer layer is a recycled plastic made of the same kind of plastic that can be thermally welded to the new plastic, and the opening is made of the new plastic. It is a plastic bottle consisting of Further, the present invention is a plastic bottle in which the inner layer of the main body is made of a new plastic, the outer layer is a recycled plastic made of the same kind of plastic that can be thermally welded to the new plastic, and the opening and the neck are made of the new plastic.

Further, the present invention provides the plastic bottle, wherein the thickness of the outer layer made of the recycled plastic is 1 to the thickness of the inner layer made of the new plastic in the laminated portion made of the recycled plastic and the new plastic. It is a plastic bottle having a size of 0.3 to 5.0. Still further, the present invention is the plastic bottle, wherein the plastic is polyester. Further, the present invention is the plastic bottle, wherein the polyester is polyethylene terephthalate.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Plastics used in the present invention include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyvinylidene chloride, polyamide, polycarbonate, polymethacrylate, polyacrylate, polyacrylonitrile, polyester, and the like. Examples thereof include polymers and polymer mixtures, and polyester is particularly preferable. As the polyester, at least one structural unit selected from ethylene terephthalate, ethylene-α, β-bis (2-chlorophenoxy) -ethane-4,4′-dicarboxylate and ethylene-2,6-naphthalate units is mainly used. What is used as a component is mentioned. These plastics include plasticizers, lubricants,
Additives such as pigments, dyes, and clarifiers may be included.

The recycled plastic used in the present invention is:
It is the same kind of plastic that can be heat-sealed with nascent plastic, and is usually manufactured by reclaiming waste plastic products. For example, after washing used waste plastic products,
After being crushed into flakes by a crusher and washed, other resins and impurities contained in a small amount in water are separated by specific gravity, dehydrated by centrifugation, and dried by hot air. Thereafter, in order to remove impurities such as an adhesive, the substrate is washed again and dehydrated and dried. The flake-shaped plastic thus obtained is heated and melted, extruded into strands, cooled, and finely cut into pellet-shaped recycled plastic raw materials. Further, the waste plastic product can be used as a recycled plastic raw material simply by crushing. The term “new plastic” as used in the present invention refers to an unused plastic that has not been commercialized or recycled, and the same kind of plastic is a plastic having substantially the same molecular structure as a main component and is mutually heated. It means what can be welded.

The present invention will be described below with reference to the drawings. FIG.
FIG. 5 is an explanatory view showing an example of a plastic bottle, which includes a body portion (2) corresponding to a body, a neck portion (3) having a screw portion screwed to a lid portion (not shown) on an outer surface, and an opening. (4). The main body part (2) and the neck part (3) of the tubular body (1) have a laminated structure composed of an inner layer (5) and an outer layer (6), the inner layer (5) is a new plastic, and the outer layer (6) is Made of recycled plastic. The opening (4) is made of a single layer of new plastic.

The opening (4) is 1.0 mm from the opening end (7).
~ 2.5mm length, like soy sauce,
When the contents are transferred to another container, the contents can be transferred without contacting the outer surface of the plastic bottle made of recycled plastic. The inner surface of the bottle in which the contents are accommodated and comes into contact is made of nascent plastic, and there is no problem in terms of hygiene. The bottle is
Although various mechanical properties are required depending on the contents, rigidity is particularly required in the main body (2), and it is said that the rigidity increases as the thickness of the bottle increases.

The present invention makes it easier to recycle waste plastic bottles by using a recycled plastic made of the same kind of plastic as the inner layer of the new plastic in the outer layer of the bottle that does not come into contact with the contents, and at the same time reduces the cost of bottle products. It is aimed at down. In the laminated portion composed of recycled plastic and new plastic, in particular, in the main body (2), the thickness of the outer layer composed of recycled plastic is 1.3 to 5.0, preferably 1.3 to 5.0, with respect to the thickness of the inner layer composed of new plastic. Is 1.8 to 3.0. When the thickness of the outer layer / inner layer is less than 1.3, the cost reduction of the plastic bottle is small, and when it exceeds 5.0, the mechanical properties tend to be reduced. The thickness of the inner layer of the plastic bottle varies depending on the contents, but is usually preferably 0.02 to 0.80 mm.

FIG. 2 is an explanatory view showing another embodiment of a plastic bottle, in which a main body (1) corresponding to a body is provided.
2), a neck portion (13) having a screw portion screwed to a lid portion (not shown) on the outer surface, and an opening portion (14). The main body (12) of the tubular body (11) has an inner layer (1).
5) and an outer layer (16). The inner layer (15) is made of new plastic and the outer layer (16) is made of recycled plastic. The neck (13) and the opening (14) are plastic bottles made of a single layer of new plastic.

The neck (13) and the opening (14) are made of a single layer of nascent plastic. When the contents are drinking water such as fruit juice, tea, etc., they may be drunk directly from the mouth. The contacting neck (13) and opening (1)
4) is formed of nascent plastic. Main unit (1
2) As in the bottle of FIG. 1, the inner layer (15) has a laminated structure of a new plastic and the outer layer (16) has a laminated structure of a recycled plastic in consideration of the hygiene of the contents and cost reduction. ing.

The plastic bottle shown in FIGS. 1 and 2 is manufactured by, for example, explaining the plastic bottle shown in FIG. 1 by injection molding a parison made of nascent plastic in a mold having an inner layer. . Next, the parison having the shape of the inner layer is placed in another mold, and recycled plastic obtained by melting the recycled pellet from the outside of the mold is injected into the mold from an injection port. The recycled plastic is thermally welded to the outer surface of the already formed inner layer to form the outer layer, and a multilayer preform is obtained. This multilayer preform is placed in a bottle mold having a larger volume than the main body of the preform, and after heating, the gas is blown into the multilayer preform to expand the multilayer preform main body, and the plastic bottle shown in FIG. Is obtained. FIG.
Is manufactured in a similar manner.

[0014]

EXAMPLE A polyethylene terephthalate (RT-543, manufactured by Nippon Unipet Co., Ltd.) was melted at 280 ° C., and a parison having an inner layer (5) shown in FIG. 1 was injection-molded. Next, the parison is transferred to another mold. Thereafter, pellets of the recycled polyethylene terephthalate obtained by hot-melting the used PET bottle molded with the polyethylene terephthalate through the steps of pulverization, washing, dehydration and drying are used to obtain 280 pellets.
C., melted at a temperature of .degree. C., injected through a mold inlet, and laminated on the outer surface of the parison in the form of an outer layer (6) shown in FIG. 1 to produce a multilayer preform. This multilayer preform is placed in a bottle mold having a larger volume than the main body of the preform, and
8. Heat to a temperature range of 0 ° C. to 120 ° C., blow air into the inside of the multilayer preform to expand the main body of the preform to the size of a mold, and obtain an area magnification (length × width) of 9.
It was biaxially stretched eight times to produce a bottle (1) shown in FIG. In the shape of the bottle (1) in FIG. 1, the thickness of the inner layer (5) and the outer layer (6) in the multilayer preform body (2) is variously changed, and the body ( 2) Table 1 shows the tensile modulus of the wall surface. The tensile modulus is determined by cutting out the wall of the main body (2) of the pottle (1),
According to MD-882, it measured at 25 degreeC and 65% RH using an Instron type tensile tester.

[0015]

[Table 1]

As is apparent from Table 1, as the wall thickness of the bottle body increases, the tensile modulus increases, and the rigidity of the bottle increases.

[0017]

According to the present invention, the recycling of plastic bottles is facilitated by using the same kind of plastic materials that can be welded to each other, and the cost is reduced by using recycled plastic for the outer layer of the bottle body. It is intended to impart rigidity to the bottle.
Also, since the inner layer, opening or / and neck of the bottle are made of nascent plastic, the plastic bottle of the present invention is used for the problems of conventional plastic bottles, that is, for applications requiring hygiene and rigidity. The present invention solves the cost and environmental problems of a bottle made of different materials at once.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of the plastic bottle of the present invention.

FIG. 2 is an explanatory view showing another example of the plastic bottle of the present invention.

[Explanation of symbols]

 1,11 Bottle 2,12 Body 3,13 Neck 4,14 Opening 5,15 Inner layer 6,16 Outer layer

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B29L 9:00 B29L 22:00 22:00 B65D 1/00 B (72) Inventor Yoshihisa Hama Hanazonocho, Otsu City, Shiga Prefecture 7F term at address 15 (reference) 3E033 AA02 BA17 BA18 BB08 CA03 CA06 DA03 FA03 GA02 4F100 AK01A AK01B AK41A AK41B AK42A AK42B BA02 BA15 BA25 DA01 DA04 EH36 EJ38 GB16 JK01 JL12B JL16B4A01LB02A03A02A24A02A04A02A02A02 LG03 LG06 LG13 LG16 LG28 LH02 LJ01 LJ05

Claims (5)

[Claims] 1. A plastic bottle in which the inner layer of the main body and the neck is made of a new plastic, the outer layer is a recycled plastic made of the same kind of plastic that can be thermally welded to the new plastic, and the opening is made of the new plastic. 2. A plastic bottle in which the inner layer of the main body is made of nascent plastic, the outer layer is made of recycled plastic made of the same kind of plastic that can be thermally welded to the nascent plastic, and the opening and the neck are made of the nascent plastic. 3. The laminated portion made of recycled plastic and nascent plastic, wherein the thickness of the outer layer made of recycled plastic is 1.3 to 5.0 with respect to the thickness of the inner layer made of nascent plastic. The plastic bottle according to 1 or 2. 4. The plastic bottle according to claim 1, wherein the plastic is polyester. 5. The plastic bottle according to claim 4, wherein the polyester is polyethylene terephthalate.