| 摘要 |
<p>PURPOSE:To obtain a heat-insulating material, having a small volume during its storage or transportation, which can be easily thickened for use in the field, by interposing a soft foam between two plastic sheets, and sealing the four side end parts of the plastic sheets under a specified condition. CONSTITUTION:A soft foam 3, in a state containing air in it, is interposed between two plastic sheets 1, 1. The both side end parts of the plastic sheets 1, 1 are heat- welded between side-seal rolls 4, 4. Thereafter, the plastic sheets are passed through compression rolls 5, 5 to purge the contained air from the soft foam 3 and to form the whole of the sheets into a flat shape. The plastic sheets are then heat-welded at a right angle to its longitudinal direction.</p> |
