| 摘要 |
<p>A low melting enamel frit capable of firing at temperatures lower than the A<Sub>1</Sub> transformation temperature of steel, say 723°C, comprises 31 to 39 wt% of SiO<Sub>2</Sub>, 13 to 21 wt% of B<Sub>2</Sub>O<Sub>3</Sub>. 14 to 21 wt% of Na<Sub>2</Sub>O. 1 to 5 wt% of K<Sub>2</Sub>0, 5 to 20 wt% of ZnO, 2 to 10 wt% of F<Sub>2</Sub> and 2 to 9 wt% of at least one of Al<Sub>2</Sub>O<Sub>3</Sub>, Zr0<Sub>2</Sub> and TiO<Sub>2</Sub>, each intermediate oxide being present in an amount of at most 5 wt%, provided that the Si0<Sub>2</Sub>/B<Sub>2</Sub>0<Sub>3</Sub> ratio by weight is from 1.5 to 3.0:1;
<UnorderedLists id="ula01" listStyle="none"><ListItem>the total amount of ZnO, Al<Sub>2</Sub>O<Sub>3</Sub>, Ti0<Sub>2</Sub> and Zr0<Sub>2</Sub> is from 17 to 25 wt%;</ListItem><ListItem>the ZnO/(ZnO + Al<Sub>2</Sub>O<Sub>3</Sub> + TiO<Sub>2</Sub> and Zr0<Sub>2</Sub>) ratio by weight is from 0.65 to 0.90:1;</ListItem><ListItem>the total amount of Na<Sub>2</Sub>O + K<Sub>2</Sub>O is from 16 to 23 wt%;</ListItem><ListItem>the (ZnO + Al<Sub>2</Sub>O<Sub>3</Sub> + Ti0<Sub>2</Sub> + Zr0<Sub>2</Sub>)/(Na<Sub>2</Sub>O + K<Sub>2</Sub>0) ratio by weight is from 0.85 to 1.2:1; and</ListItem><ListItem>the (SiO<Sub>2</Sub> + B<Sub>2</Sub>O<Sub>3</Sub> + F<Sub>2</Sub>)/(Na<Sub>2</Sub>0 + K<Sub>2</Sub>0 + ZnO) ratio by weight is from 1.3 to 2.0:1.</ListItem></UnorderedLists></p> |
