PET container for foods and drinks containing recycled resin and having DLC coating film formed on surface thereof

Abstract

A PET container for foods and drinks having a DLC coating film formed on the inner surface thereof, characterized in that the PET container for foods and drinks is produced by the use of a molding material comprising a mixture of a recycled resin which is originated from a used PET container for foods and drinks and has not subjected to a treatment for adjusting its intrinsic viscosity with a fresh PET resin. The above PET container for foods and drinks can provide satisfactory barrier properties against a pollutant substance being present in a resin.

Description

[0001] This application is a divisional application of Ser. No. 10 / 149,336, filed Jun. 6, 2002.TECHNICAL FIELD [0002] The present invention is related to a plastic container adapted for use as a food container or the like, and in particular to a plastic container containing recycled PET resin which makes it possible for the resin of a used PET (polyethylene terephthalate) container for foods and beverages to be recycled and used again as a plastic container for foods and beverages, and a manufacturing method thereof PRIOR ART TECHNOLOGY [0003] Japanese Laid-Open Patent Publication No. HEI 8-53117 discloses a vapor deposition apparatus which uses CVD (Chemical Vapor Deposition, chemical vapor growing method), in particular, a plasma CVD method to vapor deposit a DLC (Diamond Like Carbon) film on the inner surface of a plastic container in order to improve the gas barrier properties and the like of containers such as containers for carbonated beverages and high fruit juice beverages a...

AI Technical Summary

Benefits of technology

[0009] However, with regard to the system of {circle over (1)}, it is built at the same time recycled products flow to market, and with regard to {circle over (2)}, it is difficult to find fundamental users of recycled products as restrictions are made to use. With regard to {circle over (3)}, the required cost for the process of low molecular conversion of resin is high, and becomes disadvantageous by a cost comparison with new resin. Accordingly, the {circle over (4)} conception of a means to prevent contaminants from eluting into the contents even when a small amount of unknown contaminants remain is thought to be realistic.

[0027] In accordance with the invention described in claim 4, it is possible to provide a method of manufacturing a DLC film coated PET container for foods and beverages containing recycled resin which has sufficient container strength and sufficient contaminant elution barrier properties, wherein a sufficient amount of unused PET resin pellets is mixed in to make it possible to mold a container using inexpensive pelletized resin of used PET containers for foods and beverages which has not undergone a solid phase polymerization process.

Problems solved by technology

Namely, in general after a food container package is consumed / used for the original purpose, due to contact with a foreign substance and foreign substance mixing and the like in the use for another purpose, unexpected misuse, or discarding / recycling process, a risk of contamination is expected due to the unknown substance.

However, with regard to the system of {circle over (1)}, it is built at the same time recycled products flow to market, and with regard to {circle over (2)}, it is difficult to find fundamental users of recycled products as restrictions are made to use.

With regard to {circle over (3)}, the required cost for the process of low molecular conversion of resin is high, and becomes disadvantageous by a cost comparison with new resin.

Images