| 摘要 |
A method and mould for moulding material requiring heat treatment for setting or curing, e.g., for making ophthalmic lenses. The mould comprises an annular gasket and two opposed die members which together define a moulding cavity. One of the die members is made in part of a fusible material, e.g. paraffin wax, which defines its moulding surface. After filling the mould the moulding material is subjected to heat treatment. The drop point or softening point of the fusible material falls within the range of temperatures of heat treatment so that in the course of such heat treatment of fusible material effectively releases the moulded material. This relieves stresses which would otherwise develop due to shrinking of the moulded material.
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