Food container having an inner protecting layer

Abstract

A food container includes: a container body made of paper, and having an inner surface defining a receiving space therein, and an outer surface opposite to the inner surface; and an inner protecting layer coated on the inner surface and made from a biodegradable coating composition including polybutylene succinate as a major component. The biodegradable coating composition further includes a minor component selected from polybutylene adipate/terephthalate, polylactic acid, and combinations thereof.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority of Taiwanese application No. 098102514, filed on Jan. 22, 2009.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates to a food container, more particularly to a food container that includes an inner protecting layer made from a biodegradable coating composition including polybutylene succinate.[0004]2. Description of the Related Art[0005]Disposable food containers are primarily made of paper and plastic. Because plastic containers are generally not biodegradable and paper can be decomposed easily and recycled, paper containers are now more popular than the plastic containers.[0006]Referring to FIG. 1, a conventional paper cup 1 includes a paper cup body 11 with an inner surface 111 defining a receiving space 13 therein, and a protecting layer 12 coated on the inner surface 111. The protecting layer 12 is formed by coating a melted low-density polyethylene (LDPE) on the inner...

AI Technical Summary

Problems solved by technology

However, as low-density polyethylene can not be easily decomposed in natural environment, it is not environmentally friendly.

However, since polylactic acid has a glass transition temperature ranging from 58° C. to 60° C. and has poor heat resistance, the protecting layer made of polylactic acid is easily peeled off from the paper cup when hot liquid is poured into the paper cup, thereby causing the liquid to seep into and damage the paper cup.

Therefore, when a polylactic acid coating is coated on a paper sheet, because the polylactic acid coating is relatively hard and has low adhesion strength at room temperature, it is likely to peel off during processing, thereby resulting in poor yield and hence high manufacturing costs.

However, as most surfactants are toxic, when a surfactant is applied to the cup body, the surfactant can be released into the liquid received in the paper cup.

Images