Discharge container

1. A discharge container comprising:

a double-walled container body including (i) an inner layer body which defines a containment space that contains a content containing some solid content and is deformable in a volume-reducing manner, and (ii) an outer layer body surrounding the inner layer body;

a discharge cap having a discharge outlet through which the content is discharged, the discharge cap being attached to a mouth of the double-walled container body; and

a check valve structure which is disposed inside the discharge cap and allows a flow of the content from the containment space toward the discharge outlet and prevents backflow from the discharge outlet toward the containment space,

wherein the check valve structure is provided as a valve member that has a tubular partition wall defining a flow path of the content from the containment space toward the discharge outlet and a valve body which is provided on the tubular partition wall with a hinge portion and has a single swing structure swung on the hinge portion,

the valve member is retained inside the discharge cap by a valve retaining member having a partition wall portion that covers an upper opening of the inner layer body and a retainer tube hanging down from an inner peripheral edge of the partition wall portion,

the tubular partition wall extends upward from an inside of the retainer tube, and a vertical length of the tubular partition wall is longer than a maximum diameter of the single swing structure, and

the content has a viscosity such that, in a state in which the solid content prevents the valve body from achieving a completely closed state of the valve structure after discharge of a first portion of the content, a second portion of the content remains in a space inside the tubular partition wall that serves as a liquid reservoir space, the second portion of the content forming a liquid seal that restricts ambient air from reaching a third portion of the content that remains in the containment space.

2. The discharge container according to claim 1 , wherein the viscosity of the content is 100 mPa·s or more.

3. The discharge container according to claim 2 , wherein a diameter of a piece of the solid content contained in the content is less than 1.5 mm.

4. The discharge container according to claim 1 , wherein a diameter of a piece of the solid content contained in the content is less than 1.5 mm.

5. The discharge container according to claim 1 , further comprising a projection integrally provided at a central portion of an upper surface of the valve body, the projection adding to rigidity of the valve body.

6. The discharge container according to claim 1 , wherein the inner layer body is formed of ethylene vinyl alcohol copolymer, nylon or polypropylene.

7. The discharge container according to claim 1 , wherein the inner layer body is sandwiched between the outer layer body and the valve retaining member.

8. A discharge container comprising:

a double-walled container body including an inner layer body which defines a containment space for a content and is deformable in a volume-reducing manner and an outer layer body surrounding the inner layer body, the inner layer body being formed of ethylene vinyl alcohol copolymer, nylon or polypropylene;

a discharge cap having a discharge outlet through which the content is discharged, the discharge cap being attached to a mouth of the double-walled container body; and

a check valve structure which is disposed inside the discharge cap and allows a flow of the content from the containment space toward the discharge outlet and restricts backflow from the discharge outlet toward the containment space,

wherein the check valve structure is provided as a valve member that has a tubular partition wall defining a flow path of the content from the containment space toward the discharge outlet and a valve body which is provided on the tubular partition wall with a hinge portion and has a single swing structure swung on the hinge portion,

the valve member is retained inside the discharge cap by a valve retaining member having a partition wall portion that covers an upper opening of the inner layer body and a retainer tube hanging down from an inner peripheral edge of the partition wall portion,

the tubular partition wall extends upward from an inside of the retainer tube, and a vertical length of the tubular partition wall is longer than a maximum diameter of the single swing structure, and

space inside the tubular partition wall above the valve body serves as a liquid reservoir space where part of remaining content is stored after the discharge of the content.

9. The discharge container according to claim 8 , wherein the inner layer body is sandwiched between the outer layer body and the valve retaining member.

10. A discharge container comprising:

a double-walled container body including an inner layer body which defines a containment space for a content and is deformable in a volume-reducing manner and an outer layer body surrounding the inner layer body;

a discharge cap having a discharge outlet through which the content is discharged, the discharge cap being attached to a mouth of the double-walled container body; and

a check valve structure which is disposed inside the discharge cap and allows a flow of the content from the containment space toward the discharge outlet and restricts backflow from the discharge outlet toward the containment space,

wherein the check valve structure is provided as a valve member that has a tubular partition wall defining a flow path of the content from the containment space toward the discharge outlet and a valve body which is provided on the tubular partition wall with a hinge portion and has a single swing structure swung on the hinge portion,

the valve member is retained inside the discharge cap by a valve retaining member having a partition wall portion that covers an upper opening of the inner layer body and a retainer tube hanging down from an inner peripheral edge of the partition wall portion,

the tubular partition wall extends upward from an inside of the retainer tube,

a vertical length of the tubular partition wall is longer than a maximum diameter of the single swing structure,

the tubular partition wall, the valve body and the hinge portion are formed together as a single piece from a same material, and

space inside the tubular partition wall above the valve body serves as a liquid reservoir space where part of remaining content is stored after the discharge of the content.

11. The discharge container according to claim 10 , wherein the inner layer body is sandwiched between the outer layer body and the valve retaining member.