JP3267754B2 - How to determine recycled plastic - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining the number of times a recycled plastic product has been recycled.

[0002]

2. Description of the Related Art In recent years, since earth resources are finite,
The plastic recycling campaign is actively pursued. In many cases, physical properties such as mechanical properties and thermal properties are changed depending on the number of times plastic is regenerated. Plastic products are used for various purposes, and in the construction field, they are used for concrete forms, dams, pallets for transporting materials and equipment, soundproof mesh, and the like, and recycled plastic products are appearing on the market.

[0003] When such a recycled plastic product is used on site, the physical properties vary depending on the number of times the plastic constituting the product is recycled. Therefore, the use of the plastic product must be changed in accordance with the number of times of recycling. It is necessary to determine the number of times the plastic is recycled. Also,
In a plastic recycling plant, before molding a recycled plastic product, it is necessary to determine the number of times the plastic as a material is recycled and then determine what kind of product to use.

[0004] On the other hand, the number of times the plastics constituting a product are reproduced cannot be visually determined at all. Therefore, when judging the number of times of regenerating the plastic constituting the product, conventionally, several g are sampled from each, and a physical property test is performed on tensile strength, glass transition point, softening point temperature, and the like.

[0005]

However, in such a physical property test of a plastic, it is necessary to prepare a separate test piece for each of a plurality of test items, and several points are required for each test item. It takes a considerable number of days because data is required, and furthermore, when performing each test, a special device and a skilled technician are required, and there is a problem that the number of times of plastic regeneration cannot be easily determined. The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a method for discriminating recycled plastic in which the number of times of plastic reproduction can be easily determined.

[0006]

In order to achieve the above object, the present invention provides a method for producing a product by mixing a colorant into a different color by mixing a colorant into the plastic every time the plastic is regenerated and molded. It is characterized in that the number of times the plastic is reproduced is determined based on the color given to the product.

Further, the present invention is characterized in that the hue of the color is changed from a light color system to a dark color system each time the color is reproduced a number of times. Further, the present invention is characterized in that the color has a single hue, and is changed so that the density of the hue increases as the number of reproductions increases.

[0008]

First, a first embodiment in which the present invention is applied to a pallet for transporting materials and equipment will be described. FIG. 1 is a perspective view of three pallets having different numbers of times of reproduction. 1 is a pallet formed by the first regeneration, that is, a pallet molded by the second regeneration, 3 is a pallet molded by the third regeneration, and each pallet is It is made of plastic, and in this embodiment, polyethylene is used as plastic. Each pallet 1,
Nos. 2 and 3 are colored with a hue that changes from a light color system to a dark color system as the number of reproductions increases, and are colored yellow, orange, and brown in the embodiment. Pallets 1, 2, and 3 are colored after the plastic material is melted.
Performed before pallet molding. Coloring is performed by mixing a colorant such as a pigment or a dye into a plastic material, and the colorant is preferably decomposed by heating and does not change. Such colorants include organic pigments such as azo pigments, phthalocyanine pigments, andraquinone pigments, and other condensed polycyclic pigments (isoindolin, quinacridone, and perylene), cadmium red, red iron, and the like.
Inorganic pigments such as molybdenum red, graphite, yellow iron, titanium yellow, cobalt blue and carbon black, and dyes such as anthraquinone, perinone and azo can be used.

According to such a configuration, the pallets 1,
By recognizing the colors 2 and 3, it is possible to instantaneously determine the number of times the plastics constituting the pallets 1, 2 and 3 are reproduced, and to grasp the physical properties of the plastics. Therefore, the pallets 1, 2 and 2, which have different numbers of times of reproduction, such as the first pallet 1 made of recycled plastic is used for transporting heavy objects, and the third pallet 3 made of recycled plastic is used for transportation of light objects. Even if 3 are mixed, recycled plastic pallets 1, 2, and 3 can be used efficiently according to the physical properties.

Next, a second embodiment will be described. Second
In the examples, the first pallet made of recycled plastic was colored light brown, the second pallet made of recycled plastic was colored slightly light brown, and the third pallet made of recycled plastic was colored dark brown. That is, in the second embodiment, the number of times of reproduction is determined by changing the density of the same hue. In this case, each pallet can be obtained by changing the amount of colorant mixed. According to the second embodiment, by determining the hue density of the palette, the number of times of reproduction of the plastic constituting the pallet can be instantaneously determined as in the first embodiment. , The pallet made of recycled plastic can be used efficiently according to its physical properties.

The three types of pallets 1 and 2 according to the first embodiment
Each of the sheets 2 and 3 was molded into 10 sheets, and an operation of selecting the pallet 1 formed by the first regeneration was performed. Also, the second
Each of the three types of pallets according to the example was molded into 10 pallets, and an operation of selecting the pallets molded in the first regeneration was performed. In addition, a pallet formed by the first regeneration without coloring at all, a pallet molded by the second regeneration without coloring at all, and a pallet molded by the third regeneration without coloring at all are molded ten times each. Work to select a pallet formed by recycling. 1st, 2nd
In the case of the pallets according to the examples, the sorting operation was completed in one hour. However, in the case of the uncolored pallets, the sorting operation required about 3 days because of the physical property test.

[0012]

As is apparent from the above description, according to the method for discriminating recycled plastic according to the present invention, each time a plastic is recycled and a product is molded, a colorant is mixed into the plastic to obtain a different color. The number of times plastics are colored and made up of products are determined based on the colors attached to the products.Thus, the number of times plastics are recycled can be determined instantly without the need for laborious and laborious physical property tests. Even when recycled plastic products having different numbers of times of reproduction are mixed, the recycled plastic products can be used efficiently according to the physical properties of the number of times of reproduction.

[Brief description of the drawings]

FIG. 1 is a perspective view of three pallets having different numbers of times of reproduction.

[Explanation of symbols]

 1 Pallet molded in the first regeneration 2 Pallet molded in the second regeneration 3 Pallet molded in the third regeneration

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29B 17/00-17/02 C08J 11/00-11/28 B09B 3/00-5/00 C08J 5 / 00-5/02 C08J 5/12-5/22 106 C08K 3/00-13/08 C08L 1/00-101/16

Claims (3)

(57) [Claims] 1. Each time a plastic is recycled and a product is molded, a colorant is mixed into the plastic and colored in a different color, and the number of times the plastic constituting the product is recycled based on the color applied to the product. A method for determining recycled plastic, characterized in that the recycled plastic is determined. 2. The method according to claim 1, wherein the hue of the color is changed from a light color to a dark color each time the number of times of reproduction is increased. 3. The method according to claim 1, wherein the color is a single hue, and is changed so that the density of the hue increases as the number of times of reproduction increases.