Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
128 words
A process according to which a cellular sheet of plastic is extruded from an extruding means and then at least one protective film of plastic is joined to at least one of its surface layers, said protective film having a softening temperature lower than that necessary for extruding the sheet, wherein the protective film and a support film are heated and pressed together so as to form a bonded layer, then this bonded layer is laid on the surface of the cellular sheet emerging from the extruding means, with the protective film in contact with the cellular sheet, cooling the combination of cellular sheet, protective film and support film, and removing said support film from the cooled combination leaving the extruded sheet now integral with the protective film.
Claim 2
Dependent Claim
128 words
A process according to which a cellular sheet of plastic is extruded from an extruding means and then at least one protective film of plastic is joined to at least one of its surface layers, said protective film having a softening temperature lower than that necessary for extruding the sheet, wherein the protective film and a support film are heated and pressed together so as to form a bonded layer, then this bonded layer is laid on the surface of the cellular sheet emerging from the extruding means, with the protective film in contact with the cellular sheet, cooling the combination of cellular sheet, protective film and support film, and removing said support film from the cooled combination leaving the extruded sheet now integral with the protective film.
Claim 3
Dependent Claim
17 words
A process according to claim 1, wherein the support film is made of fluoridated resin or polyester.
Claim 4
Dependent Claim
23 words
A process according to claim 1, wherein said support film has a softening temperature around 260° C. and is about 100 um thick.
Claim 5
Independent Claim
122 words
An apparatus for carrying out the joining of a protective film to an extruded cellular sheet, comprising a die box for extruding the sheet, means for guiding the protective film and a support film, resistors and rollers for heating and pressing together the protective film and the support film so as to form a bonded layer, means for applying this bonded layer to the extruded cellular sheet, with the protective film in contact with the cellular sheet, means for guiding and pulling the bonded layer and the extruded cellular sheet while passing through a cooling-calibrating means, and at least one means for detaching and rewinding the support film, after the application of the protective film to the cellular sheet has been accomplished.
Claim 6
Independent Claim
122 words
An apparatus for carrying out the joining of a protective film to an extruded cellular sheet, comprising a die box for extruding the sheet, means for guiding the protective film and a support film, resistors and rollers for heating and pressing together the protective film and the support film so as to form a bonded layer, means for applying this bonded layer to the extruded cellular sheet, with the protective film in contact with the cellular sheet, means for guiding and pulling the bonded layer and the extruded cellular sheet while passing through a cooling-calibrating means, and at least one means for detaching and rewinding the support film, after the application of the protective film to the cellular sheet has been accomplished.
Claim 7
Dependent Claim
44 words
An apparatus according to claim 4, further comprising a cooling screen, placed between the die box and the protective film to be joined to the cellular sheet, so as to prevent heat radiation coming from the die box from excessively softening the protective film.
Claim 8
Dependent Claim
35 words
An apparatus according to claim 4, comprising a traction device acting on the sheet emerging from the cooling-calibrating device, the rewinding means of the support film being actuated by means of an adjustable clutch device.
Claim 9
Dependent Claim
35 words
An apparatus according to claim 4, comprising at least one roller about which said support film is drawn, the last-named roller being disposed where the support film separates from the cellular sheet and protective film.