Food container and method for manufacturing same

A food container, comprising a container body having an opening, and a lid for closing the opening in the container body;

• the lid having a sealing moiety for making the periphery of the opening into a sealed state under a situation that the opening in the container body is closed by the lid;
• the sealing moiety comprising an elastomer which comprises a hydrogenated styrene based block copolymer A that has a weight-average molecular weight of 100,000 to 500,000, a softener B for rubber that has a weight-average molecular weight of 500 or more, and an olefin based resin C, and which has a hardness A of 32 to 36 both inclusive, and a compressive permanent strain (CS) of between 25% to 28% at 100° C. over 24 hours;
• the sealing moiety being formed to be integrated with the lid or the container body;
• and the lid comprising a polypropylene,
• wherein the polypropylene is a polypropylene having a melting point of 155° C. or higher,
• wherein in the elastomer composition, the blend amount of the softener B for rubber is from 185.2 to 222.2 parts by mass and that of the olefin based resin C is from 25.9 to 31.1 parts by mass for 100 parts by mass of the hydrogenated styrene based block copolymer A;
• the hydrogenated styrene based block copolymer A is a hydrogenated product of a block copolymer A′ which comprises a polymer block (a) comprising a styrene based monomer and a polymer block (b) comprising a conjugated diene compound, the content by percentage of the polymer block (a) comprising the styrene based monomer being 33% by mass;
• and
• the softener B for rubber is a softener having a molecular weight distribution index (weight-average molecular weight (Mw)/number-average molecular weight (Mn)) of 4.0 or less;
• the food container has a flange on the outside surface of a peripheral wall of the container body, wherein a projection is formed at the outer circumferential edge so as to be downward projected;
• the lid has a fixing portion, wherein hooks are formed to have an L-shaped cross section in order to fit the projection;
• the sealing moiety is formed so as to be arranged between the lid and the upper end surface of the peripheral wall of the container body when the opening of the container body is closed by the lid;
• the sealing moiety is provided with a contacting portion which is to contact a predetermined site of the upper end surface of the peripheral wall of the container body, and the contacting portion is formed with a predetermined width to be made, as a whole, into a planar form;
• and
• the upper end surface of the peripheral wall of the container body that contacts the contacting portion includes a contacting surface portion on a planar shape that contacts the contacting portion.