JPS60281A - Heat-insulating box body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat insulating box body in which hard urethane foam is integrally foamed between an inner box and an outer box.

Conventionally, when hard urethane foam was integrally foamed on-site in a heat-insulating box body consisting of an inner box made of ABS resin, the ABS resin was chemically attacked by Freon 11 in the hard urethane foam, resulting in deterioration of the physical properties of the ABS resin. When stress was applied, it caused whitening and breakage, significantly reducing the quality of the insulation box.

Therefore, measures have been taken to prevent direct contact with Freon 11 by covering the inner box with polyethylene film and securing it with tape, or by applying PVA (polyvinyl alcohol) to form a thin film, but the workability of securing with tape has been reduced. badness and
In the case of PVA coating, it takes a long time to dry, and the permeation of Freon 11 can be completely blocked, so it does not have a sufficient effect.

The present invention aims to improve the drawbacks of the above-mentioned conventional examples.

An embodiment of the present invention will be described below with reference to the drawings.

1 is an insulated box for a refrigerator, which includes an inner box 2, an outer box 3, and both boxes 2.
, 3, and a hard urethane foam 4 such as polyurethane foam using Freon 11 as a blowing agent. Reference numeral 6 denotes a urethane layer using water as a foaming agent. This urethane layer 6 is provided in a thin wall portion, a stress concentration area, such as a rear corner, of the inner box 2 before integrally foaming the urethane. and a boundary layer of the hard urethane foam 4 using Freon 11 as a foaming agent.

As described above, the present invention involves forming a urethane layer using water as a foaming agent in advance on the thin wall part, stress concentration area, or the entire surface of the inner box, and then on-site integration of a hard urethane foam using Freon 11 as a foaming agent. It foams, and water that does not contain Freon 11 is used as a boundary layer as a foaming agent in the thin wall part, stress concentration part, or the entire surface of the inner box made of resin, etc., which is exposed to the chemical attack of Freon 11. Since a urethane layer is formed, it is possible to prevent Freon from permeating and greatly suppress deterioration of the ABS resin inner box.

As mentioned above, in the present invention, a hard urethane foam is foamed between an inner box and an outer box, and a urethane layer using water as a foaming agent is previously provided on the surface of the inner box or its stress concentration area. Since it forms a skin by water foaming, it can prevent the chemical attack of Freon 11.
Deterioration of the inner box material can be significantly suppressed compared to conventional methods. Moreover, those using water or Freon 11 as a foaming agent have the same heat insulation effect as a heat insulating material, and do not impair the heat insulation performance.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a sectional view of a heat insulating box according to an embodiment of the present invention;
FIG. 2 is an enlarged sectional view of the main part of FIG. 1. 1... Insulated box body, 2... Inner box, 4...
・Hard urethane foam, 6゛・・Urethane layer.

Claims (1)

[Claims] A heat insulating box in which a hard urethane foam is integrally foamed between an inner box and an outer box made of synthetic resin, characterized in that a urethane layer using water as a foaming agent is provided on the surface of the inner box or its stress concentration area. .