粘合剂对火蔓延的影响

1．前言 目前，各种天然及合成高分子材料已被广泛用于建筑、室内装潢以及家具等行业。尤其值得注意的是，粘合剂是其中不可缺少的高分子物质，在日本各类粘合剂的年总产量约110万吨1），其中属于热固性树脂（脲醛树脂）和热塑性树脂（水溶性聚醋酸乙稀，PVAC）的粘合剂各占10％左右。然而，一旦建筑发生火灾时，可以想像这些材料中所含有的高分子物质将对燃烧的过程与现象产生影响。

Effects of Adhesives on Flame Spread

This paper presents the result of the effects of the adhesive on the flame spread phenomena were discussed. A study has been performed on the heat transfer near the leading flame edge spreading over a cellulose sheet permeated with an adhesive. The test pieces used were filter paper sheets permeated various amounts of adhesive, polyvinyl acetate resin or urea resin. The temperature distribution of the gas phase and test piece surface near the leading flame edge spreading over each test piece was measured using a set of fine thermocouples, and on the basis of the results, the details of heat transfer were evaluated. Either of the isotherms near the leading flame edge spreading over a filter paper sheet permeated with polyvinyl acetate resin or urea resin was shown to be almost the same with that over a pure filter paper except for a slight shift of the higher temperature region of the former to the sheet surface. The amount of heat transferred through gas phase to the pure filter paper sheet was indicated to be larger than that to the filter paper sheet permeated with an adhesive. This was inferred to be the main cause to decrease the mass burning rate with polyvinyl acetate resin permeation. In addition to this effect, radiative heat loss from the surface was inferred to be effective for reducing the mass burning rate with urea resin permeation to extinction.