Patent ID: 6261490
Filing Date: 2001-07-17
Classification: B29C

Abstract:
A method of producing a plastics article having solid skin and a foam core by a rotational moulding process, the method comprising:charging a mould with a skin-forming component including a first plastics material in the form of a comparatively fine powder and substantially simultaneously with a foam core-forming component including a second plastics material and a blowing agent in the form of comparatively large pellets,providing a first heating stage in which the mould is heated in an oven to a first controlled temperature that is equal to the melting temperature of the first plastics material plus 0-10.degree. C., said first controlled temperature being sufficient to melt the first plastics material without causing foaming of the second plastics material and the mould is rotated for a first predetermined time to form within the mould a skin,providing a second heating stage in which the oven temperature is increased so that the mould is heated to a higher second controlled temperature that is sufficient to cause foaming of the second plastics material and is rotated for a second predetermined time to cause foaming of said foam core-forming component, thereby forming a foam core within said skin.