Oxygen scavenging and heat-generating compositions and deoxygenating and heat-generating structures comprising these compositions.

摘要

An oxygen scavenger composition consisting essentially of
<UnorderedLists id="ula01" listStyle="none"><ListItem>(a) metallic iron, and</ListItem><ListItem>(b) at least one oxidation promoter selected from the group consisting of sodium silicate hydrates, silicic acid, sodium alum and sodium borate hydrates, and</ListItem></UnorderedLists>
optionally
<UnorderedLists id="ula02" listStyle="none"><ListItem>(c) at least one oxidation promoter aid which is a metal halide compound, and/or</ListItem><ListItem>(d) a water-insoluble or sparingly water-soluble inert filler;
<UnorderedLists id="ula03" listStyle="none"><ListItem>a heat-generating composition having an initial rate of oxygen scavenging of at least 5 mi per gram of said composition in the air at 20°C during a period of one hour after the oxidation reaction has substantially begun, said composition consisting substantially of the metallic iron (a), a sodium silicate hydrate, and/or silicic acid as an oxidation promoter (b), the oxidation promoter aid (c) and optionally the filler (d);</ListItem><ListItem>a deoxygenating structure comprising the oxygen scavenger composition and a film having an oxygen permeability of at least 0.005 ml/cm<Sup>2</Sup>.min.atm. (0<Sub>2</Sub> partial pressure) covering said composition; and</ListItem><ListItem>a heat-generating structure comprising the heat-generating composition and a film having an oxygen permeability of 0.4 to 10 ml/cm<Sup>3</Sup>.min.atm (0<Sub>2</Sub> partial pressure) covering said composition.</ListItem></UnorderedLists></ListItem></UnorderedLists>