Expanded rubber articles

A process for making an expanded rubber article, wherein the expanded rubber article is a moulded tyre, the process comprising:

• a) a moulded blank formation step, in which an expandable rubber formulation, comprising an elastomeric material, a curing agent and an expansion agent, is heated in a first mould cavity to partially cure the expandable rubber formulation thereby forming a moulded blank, wherein the first mould cavity confines expansion of the expandable rubber formulation;
• b) a releasing step, in which the moulded blank is released from the first mould cavity, and in which the moulded blank expands to a volume larger than the volume of the first mould cavity thereby forming an expanded moulded blank;
• and,
• c) a further curing step, in which the expanded moulded blank is heated to further cure and expand the expandable rubber formulation thereby forming the expanded rubber article;
• wherein the expanded moulded blank is heated in a second mould cavity in further curing step (c).