JP2002120254A - Injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding capable of reducing a using amount of a thermoplastic resin to reduce the weight of the molding. SOLUTION: The injection molding comprises a surface layer 31 and an interior layer 32. In this case, the layer 31 is made of a thermoplastic resin having a specific gravity of 0.88 to 1.55. The layer 32 is made of a thermoplastic resin having a specific gravity of 0.01 to 0.50.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molded product used in ordinary households.

[0002]

2. Description of the Related Art Conventionally, in an injection-molded article such as a body brush used for removing dirt from a body when taking a bath, a thick solid body is used so that the handle is easy to grasp and familiar. Is known.

[0003]

However, such an injection molded article has a problem that the weight and the cost of raw materials increase.

[0004] It is an object of the present invention to solve the above-mentioned conventional problems and to provide an injection-molded article capable of reducing the amount of thermoplastic resin used and reducing its weight.

[0005]

The injection-molded article of the present invention comprises a surface layer and an inner layer, the surface layer being a thermoplastic resin having a specific gravity of 0.88 to 1.55, and the inner layer being a specific gravity. Is composed of a thermoplastic resin of 0.01 to 0.50.

In the injection-molded article according to the second aspect of the present invention, the thermoplastic resin constituting the surface layer further comprises at least one additive selected from the group consisting of an antibacterial agent, a deodorant, and an antistatic agent. It is characterized by being contained.

In the injection molded articles according to the first and second aspects of the present invention, the means for molding the injection molded article comprising the surface layer and the inner layer is not particularly limited. In the case of sandwich injection molding in which the surface layer material is injected into the cavity and then the inner layer material is injected and filled to form the surface layer and the inner layer at the same time, a molded article that has been molded in advance is inserted into the mold cavity, and Double-shot molding, in which a surface layer is formed on the surface, may be used.

In the injection-molded article according to the first and second aspects of the present invention, the thermoplastic resin constituting the surface layer and having a specific gravity of 0.88 to 1.55 is not particularly limited. For example, polypropylene (PP), Examples include high-density polyethylene (HDPE), acrylonitrile-butadiene-styrene (ABS), polystyrene (PS), polyamide (PA), polyvinyl chloride (PVC), polycarbonate (PC), and chlorinated polyethylene (CPE).

In the injection-molded article according to the first and second aspects of the present invention, the thermoplastic resin constituting the inner layer having a specific gravity of 0.01 to 0.50 is not particularly limited. For example, foamed polystyrene (FPS) , Foamed polyethylene (FPE), foamed styrene-butadiene copolymer (FSB), and the like, and inexpensive recovered raw materials can be used.

In the injection molded article according to the second aspect of the present invention,
The thermoplastic resin constituting the surface layer contains at least one additive selected from an additive group consisting of an antibacterial agent, a deodorant, and an antistatic agent, and is used without deteriorating the function of the additive. Can be reduced.

In the injection-molded article according to the second aspect of the present invention, the antibacterial agent contained in the thermoplastic resin constituting the surface layer is not particularly limited, and those which generate silver, copper, and zinc metal ions, Those metals or inorganic antibacterial agents such as metal oxides thereof are suitably used, and examples thereof include silver nitrate, silver chloride, silver iodide, silver oxide, silver, copper bromide, copper sulfate, copper nitrate, and phosphoric acid. Copper, cuprous oxide, copper, zinc chloride, zinc iodide, zinc oxide,
Zinc and the like. The content of the antibacterial agent is 0.1-1.
Preferably, it is 0% by weight.

In the injection-molded article according to the second aspect of the present invention, the deodorant contained in the thermoplastic resin constituting the surface layer is not particularly limited, and examples thereof include activated carbon, carbon fiber, zeolite, and silica gel. No. The content of the deodorant is preferably 0.1 to 1.0% by weight.

In the injection-molded article according to the second aspect of the present invention, the antistatic agent contained in the thermoplastic resin constituting the surface layer is not particularly limited, and examples thereof include poly (oxyethylene) alkylamine and poly (oxyethylene) alkylamine. Nonionic antistatic agents such as (oxyethylene) alkylamides, poly (oxyethylene) alkyl ethers, poly (oxyethylene) alkylphenyl ethers, glycerin fatty acid esters, sorbitan fatty acid esters, alkyl sulfonates, alkylbenzene sulfonates, and alkyl phosphates Anionic antistatic agent, quaternary ammonium chloride,
Examples include cationic antistatic agents such as quaternary ammonium sulfate and quaternary ammonium nitrate, and amphoteric antistatic agents such as alkyl betaine, alkyl imidazoline and alkyl alanine. The content of the antistatic agent is preferably 0.1 to 0.5% by weight.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 (a) shows an injection molded product 1 of the present invention.
The side view which shows an Example, (b) is the AA end view.

In FIG. 1, reference numeral 1 denotes a substantially disk-shaped brush portion, and a brush bristle bundle 2 is planted on one surface of the brush portion 1; It has a substantially convex arc shape.

From one end of the brush part 1, a handle part 3 having a substantially flat rectangular cross section is integrally provided. The handle portion 3 is curved toward the flocked surface side, and on the flocked surface side and the three surfaces on both sides thereof,
A substantially wavy anti-slip projection 4 is provided in a protruding manner. A through-hole (not shown) is formed at the tip of the handle 3 so that the handle 3 can be hung on a hook or the like fixed to a wall or the like.

As shown in FIG. 1 (b), the handle 3 has a surface layer 31 made of PP having a specific gravity of 0.90.
And an inner layer 32 made of FPE having a specific gravity of 0.10
The PP constituting the surface layer 31 contains 0.5% by weight of an inorganic antibacterial agent, 0.5% by weight of an inorganic deodorant, and 0.1% by weight of an antistatic agent.

[0018]

Since the injection-molded article of the first aspect of the present invention is configured as described above, the amount of thermoplastic resin used can be reduced and the weight can be reduced. Since the injection-molded article according to the second aspect of the present invention is configured as described above, the amount of the additive used can be further reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of an injection-molded article of the present invention and an AA end view thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Brush part 2 Brush bristle bundle 3 Handle part 4 Anti-slip projection 31 Surface layer 32 Inner layer

Claims (2)

[Claims] The surface layer is made of a thermoplastic resin having a specific gravity of 0.88 to 1.55, and the inner layer is made of a thermoplastic resin having a specific gravity of 0.01 to 0.50. An injection-molded article characterized in that: 2. The thermoplastic resin constituting the surface layer contains at least one additive selected from an additive group consisting of an antibacterial agent, a deodorant, and an antistatic agent. 2. The injection molded article according to 1.