Abstract A method for making a shaped article having at least one integral transparent or translucent panel, the method comprising forming a blank of a cellular thermoplastic polymeric material by polymerising the continuous phase of an emulsion having an aqueous disperse phase and a continuous phase comprising one or more polymerisable liquids, then removing the water from the cellular polymeric material so formed over at least the area where the panel is desired; and pressing the blank at a temperature above the softening point of the polymeric material between two dies shaped and positioned to define the desired panel so as to remove the cellular structure of the blank therebetween and form a substantially non-cellular panel.
A method according to claim 1 in which one or more exposed surfaces of the polymeric material is strengthened by fusing a layer underlying said surface of the polymeric material to form a skin, the method comprising pressing the surface of the polymeric material with a plate at a temperature above the softening point of the polymeric material sufficiently to fuse the layer to the desired depth of skin, cooling the plate to harden the skin and subsequently withdrawing the plate.
Claim 2
Dependent Claim
25 words
A method according to claim 2 in which the skin is formed on exposed surfaces of the polymeric material before the panel is formed therein.
Claim 3
Dependent Claim
57 words
A method according to claim 3 which comprises forming a skin on both sides of the polymeric material over at least the areas where tHe panel is to be formed, heating the polymeric material to a temperature above its softening point and pressing the heated article between the two panel-forming dies to remove the cellular structure therebetween.
Claim 4
Dependent Claim
24 words
A method according to claim 4 in which the panel-forming dies are maintained at a temperature below the softening point of the polymeric material.
Claim 5
Dependent Claim
60 words
A method according to claim 1 which comprises pressing the polymeric material between the two panel-forming dies with at least one of the dies at a temperature above the softening point of the polymeric material so as to remove the cellular structure of the polymeric material therebetween, cooling the dies to harden the polymeric material, and subsequently withdrawing the dies.
Claim 6
Dependent Claim
26 words
A method according to claim 1 in which the emulsion contains fillers in sufficient quantities for panels formed in the consequential polymeric material to be translucent.
Claim 7
Dependent Claim
18 words
A method according to claim 1 in which the polymeric material is in the form of a laminate.