초록 ▼

An insulation box unit and a refrigerator of the present invention employs i) rigid urethane foam with a 8.0 MPa-or-greater bending modulus, and a 60 kg/m3-or-lower density, and ii) a vacuum insulation material. The proper bending modulus provides the insulation box unit with a substantial strength,

An insulation box unit and a refrigerator of the present invention employs i) rigid urethane foam with a 8.0 MPa-or-greater bending modulus, and a 60 kg/m3-or-lower density, and ii) a vacuum insulation material. The proper bending modulus provides the insulation box unit with a substantial strength, even in the case that the coverage of the vacuum insulation material with respect to the surface of the outer box exceeds 40%. The proper density prevents the insulation box unit from poor insulation efficiency due to undesired solid thermal conductivity. Despite of an extended use of the vacuum insulation material, the insulation box unit offers an excellent insulation efficiency and therefore accelerates energy saving. According to the recycling method of the present invention, rigid urethane foam formed of tolylene di-isocyanate composition, which was separated from refrigerator wastes, is recycled as a material of rigid urethane foam.

대표청구항 ▼

The invention claimed is: 1. An insulation box unit comprising: an inner box; an outer box accommodating the inner box therein; and an insulation layer disposed between the inner box and the outer box, the insulation layer comprising: a vacuum insulation material; and a rigid urethane foam that has

The invention claimed is: 1. An insulation box unit comprising: an inner box; an outer box accommodating the inner box therein; and an insulation layer disposed between the inner box and the outer box, the insulation layer comprising: a vacuum insulation material; and a rigid urethane foam that has a bending modulus of at least 8.0 MPa, and has a density of at most 60 kg/m3, and a coverage of the vacuum insulation material with respect to a surface area of the outer box is not less than 40% and not more than 80%, wherein the rigid urethane foam covers substantially a whole surface of the inner box. 2. The insulation box unit of claim 1, wherein the vacuum insulation material is disposed on all planes--a top, a rear, a front, a bottom, and both sides--of the insulation box unit. 3. The insulation box unit of claim 2, wherein the insulation box unit has a door, and a thickness of the insulation layer disposed on the planes, except for the door, of the insulation box unit is in a range from 20 mm to 50 mm. 4. The insulation box unit of claim 3, wherein the thickness of the insulation layer surrounding a freezing-temperature zone, except for the door, is in a range from 20 mm to 50 mm. 5. The insulation box unit of claim 3, wherein the thickness of the insulation layer surrounding a refrigerating-temperature zone, except for the door, is in a range from 20 mm to 40 mm. 6. The insulation box unit in accordance with claim 1, wherein a thickness of the vacuum insulation material is in a range from 10 mm to 20 mm. 7. The insulation box unit of claim 1, wherein the insulation box unit has at least three doors. 8. The insulation box unit of claim 1, wherein the rigid urethane foam is a reaction product generated by blending a) an isocyanate component including tolylene diisocyanate compounds with b) a pre-mix component including polyol, a foam stabilizer, a catalyst, and a foaming agent. 9. The insulation box unit of claim 8, wherein the rigid urethane foam is produced by using water as a foaming agent. 10. The insulation box unit of claim 1, wherein the vacuum insulation material contains an inorganic fiber aggregate and a gas-barrier film that covers the inorganic fiber aggregate. 11. The insulation box unit of claim 10, wherein the aggregate is a multi-layered sheet-type inorganic fiber. 12. The insulation box unit of claim 1, wherein thermal conductivity of the rigid urethane foam is at least five times and at most fifteen times of thermal conductivity of the vacuum insulation material. 13. The insulation box unit of claim 1, wherein the rigid urethane foam is disposed on both surfaces of the vacuum insulation material of the insulation layer. 14. The insulation box unit of claim 1, wherein the insulation layer on a side of the insulation box unit includes the insulation layer having the rigid urethane foam on both surfaces of the vacuum insulation material. 15. The insulation box unit in accordance with claim 2, wherein a thickness of the vacuum insulation material is in a range from 10 mm to 20 mm. 16. The insulation box unit in accordance with claim 3, wherein the thickness of the vacuum insulation material is in a range from 10 mm to 20 mm. 17. The insulation box unit in accordance with claim 4, wherein the thickness of the vacuum insulation material is in a range from 10 mm to 20 mm. 18. The insulation box unit in accordance with claim 5, wherein the thickness of the vacuum insulation material is in a range from 10 mm to 20 mm. 19. The insulation box unit in accordance with claim 15 wherein the rigid urethane foam is a reaction product generated by blending a) an isocyanate component including tolylene diisocyanate compounds with b) a pre-mix component including a polyol, a foam stabilizer, a catalyst, and a foaming agent, and wherein the polyol contains tolylene diamine polyether polyol and the foaming agent is water. 20. The insulation box unit in accordance with claim 8, wherein the polyol contains tolylene diamine polyether polyol. 21. The insulation box unit in accordance with claim 1, wherein the rigid urethane foam is a closed-cell urethane foam. 22. A refrigerator comprising: a) an insulation box unit comprising: an inner box; an outer box accommodating the inner box therein; and an insulation layer disposed between the inner box and the outer box, the insulation layer comprising: a vacuum insulation material; and a rigid urethane foam that has a bending modulus of at least 8.0 MPa, and has a density of at most 60 kg/m3, and a coverage of the vacuum insulation material with respect to a surface area of the outer box is not less than 40% and not more than 80%, wherein the rigid urethane foam covers substantially a whole surface of the inner box; and b) at least one cooling box formed in the insulation box unit; and c) a cooling device. 23. The refrigerator of claim 22, wherein the refrigerator has, on a surface, a tag on which a material type of the rigid urethane foam is recorded. 24. The refrigerator in accordance with claim 22, wherein the rigid urethane foam is a closed-cell urethane foam.