Polyolefin resin foam particles, and polyolefin resin in-mold expansion molded article

Abstract

The purpose of the present invention is to produce: polyolefin resin foam particles each of which has a large cell diameter in spite of a fact that the particles are produced using a polyolefin resin having an inorganic anti-blocking agent added thereto such as a polyolefin resin for films; and a polyolefin resin in-mold expansion molded article which comprises the polyolefin resin foam particles and has excellent beauty of the surface thereof. Provided are polyolefin resin foam particles which can be produced by expanding polyolefin resin particles each comprising a polyolefin resin composition and which have an average cell diameter of 100 to 400 [mu]m inclusive, wherein the polyolefin resin composition contains at least two types of inorganic anti-blocking agents in the total amount of 0.03 to 2 parts by weight inclusive relative to 100 parts by weight of a polyolefin resin.

Description

technical field [0001] The present invention relates to polyolefin-based resin expanded particles and a polyolefin-based resin in-mold foam-molded article composed of the polyolefin-based resin expanded particles. Background technique [0002] Polyolefin-based resin in-mold foam moldings obtained by using polyolefin-based resin expanded particles made of polyolefin-based resins have the advantages of in-mold foam moldings such as arbitrary shape, light weight, heat insulation, etc. feature. In addition, the polyolefin-based resin in-mold foam molded article is superior in chemical resistance, heat resistance, deformation recovery rate after compression, etc., compared to an in-mold foam molded article obtained using expanded polystyrene resin particles. Based on these characteristics, polyolefin-based resin in-mold foam moldings are used in various applications such as automotive interior parts, core materials for automotive bumpers, heat insulation materials, cushioning pa...

AI Technical Summary

Problems solved by technology

When such a polyolefin-based resin for films containing an inorganic anti-blocking agent is applied to expanded particles, the cell diameters of the expanded particles are remarkably miniaturized. As a result, there is a problem that the mold obtained from the expanded particles The formability of the internal foam molding is reduced, and in particular, unevenness (a phenomenon in which depressions appear between the expanded particles) or wrinkles is likely to occur on the surface of the in-mold foam molding, or the surface of the in-mold foam molding The mold transferability of the edge portion (ridge line portion) where the surfaces intersect is poor, the edge portion is not smooth, and the unevenness of the foamed particles is obvious, etc., resulting in an in-mold foam molded product with poor surface appearance

In addition, depending on the situation, there may be problems such as shrinkage of the molded foam in the mold and deterioration of dimensional accuracy.

[0005] In order to avoid such problems, it is only necessary to reduce the amount of the inorganic anti-blocking agent or not to add it, but in this case, it is difficult to use it as a film, and it will not become a general-purpose product, so it cannot be obtained cheaply (for example, Patent Document 1).

In addition, there is also a method of removing the anti-blocking agent from the general-purpose product to which the anti-blocking agent is added, but in this case, the cost also increases, and the advantage of using a general-purpose product is greatly reduced

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